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Diseases of beans
Main causative agents of bean diseases
The main bacterial pathogens of bean (Phaseolus) diseases:
- Corynebacterium flaccumfaciens pv. flaccumfaciens (Bacteria wilt);
- Pseudomonas syringae pv. syringae (Bacterial brown spot);
- Xanthomonas phaseoli, X. campestris pv. phaseoli (Common blight);
- Xanthomonas phaseoli pv. fuscans (Fuscous blight);
- Pseudomonas phaseolicola, P. syringae pv. phaseolicola (Halo blight).
Major fungal pathogens of bean diseases:
- Alternaria spp. (Alternaria leaf and pod spot);
- Isriopsis griseola (Angular leaf spot);
- Colletotrichum lindemuthianum, other species of Colletotrichum spp. (Anthracnose);
- Ascochyta spp. (Ascochyta leaf spot);
- Cercospora cruenta (Cercospora leaf spot);
- Phytophthora phaseoli (Downy mildew);
- Peronspora viciae (Fava downy mildew);
- Fusarium solani f. sp. phaseoli (Fusarium root rot);
- Fusarium oxysporum f. sp. phaseoli (Fusarium yellows);
- Botrytis cinerea (Gray mold);
- Phyllosticta phaseolina (Phyllosticta leaf spot);
- Diaporthe phaseolorum (Pod blight);
- Erysiphe polygoni (Powdery mildew);
- Pythium spp., also Aphanomyces, and Thielaviopsis spp. (Pythium root rots and damping-off);
- Rhizoctonia solani (Rhizoctonia);
- Uromyces phaseoli, other species of Uromyces spp. (Rust);
- Elsinoe phaseoli (Scab, lima bean);
- Colletotrichum truncatum (Stem anthracnose);
- Verticillium albo-atrum (Verticillium wilt);
- Sclerotinia sclerotiorum (White mold).
Viruses:
- Bean Common Mosaic Virus, BCMV;
- Bean Golden Mosaic Virus, BGMV;
- Bean Pod Mottle Virus, BPMV;
- Bean Southern Mosaic Virus, BSMV;
- Bean Yellow Mosaic Virus, BYMV, strain of bean;
- Cucumber Mosaic Virus, CMV, strain of bean;
- Sugar Beet Curly Top Virus, SBCTV;
- Peanut Stunt Virus.
Root rot
Aphanomyces root rot
Aphanomyces root rot (Aphanomyces root rot) was not a problem in beans (Phaseolus) until 1979, when a strain of Aphanomyces euteiches was identified in Wisconsin causing severe root rot (Pfender and Hagedorn, 1982). It has since been found on crops in several states in the United States and Australia.
The infection may begin early in the life of the plant or develop later, after the soil of the field has become waterlogged for a short time. The fungus affects the bark of the root system, resulting in stunting and yellowing, after which the plant wilts and dies. A. euteiches can often be found together with Pythium spp. since the latter pathogen is more common, but it is favored by similar conditions. The host range of A. euteiches f. sp. phaseoli includes alfalfa (alfalfa) as well as string beans and dry beans.
Some resistance has been found in breeding lines, but their agronomic characteristics are too far removed from commercial traits in the near future. Heavy irrigation is associated with infection, so soil moisture content and temperature are key factors in disease control in large-scale irrigated bean production. The use of green fertilizer, especially mustard, has proven useful in suppressing A. euteiches and other pathogens (Parke and Rand, 1989). The application of brown mustard, grown as a green fertilizer and then crushed and rolled into the soil, has a fumigant effect on the pathogen. Other work has shown the value of other green fertilizers along with an integrated approach to control, using resistant varieties and proper soil management, to reduce inoculum levels in the soil (Tu, 1991).
Fusarium root rot
Fusarium root rot, Fusarium foot rot, is found in most bean growing areas worldwide. The disease usually causes the most damage when the roots first become stressed by soil compaction, drought, waterlogging, or oxygen stress. Early symptoms are stunting, chlorosis of the upper leaves, and redness or browning at the base of the stem. Roots usually turn black and the base of the stem may collapse. Sometimes symptoms may appear on short sections of plants along the row when soil conditions cause stress.
Loss of plants due to infection results in lower yields. Depending on the pockets of infection in the field, yield loss can be severe. Where plants are low in height, the efficiency of mechanized harvesting is reduced.
The pathogen Fusarium solani f. sp. phaseoli remains in the soil as chlamydospores for many years. Chlamydospores germinate in the presence of host root exudates and infect root tissues. Legume fusariasis isolates from the United Kingdom have also been shown to be pathogenic on pea roots, but the symptoms are not as severe as on beans (Phaseolus).
Bean varieties vary in their sensitivity to Fusarium root rot, but none are completely resistant. Some progress in developing resistance or tolerance has recently been made through research on root growth traits (Roman-Aviles et al., 2004), and this along with soil management will be the most practical form of control.
Rhizoctonia root rot
Rhizoctonia root rot, Rhizoctonia root rot, is common throughout the world and is one of the most economically important root and hypocotyl diseases in beans. Losses occur in all types of cultivation, whether plowing and tillage, minimum tillage or direct seeding systems. The disease often occurs in conjunction with Fusarium foot rot, but the characteristic depressed reddish-edged lesions at the base of the stem are usually a lesion of Rhizoctonia solani. This disease usually occurs in warm weather and is not as much of a problem in Northern Europe as Fusarium solani.
Resistance to this disease is available in breeding lines, and some moderate resistance is present in commercial varieties; however, soil management is paramount to minimize risk and alleviate root stress early in the growing season.
Southern blight (Sclerotinia rolfsii)
Southern blight is serious in many tropical and subtropical regions of the world, where high temperatures and moist soil occur throughout the growing season. The causative agent is the fungus Sclerotinia rolfsii, which has a very wide range of hosts among both monocotyledonous and dicotyledonous plants, including many vegetables. Early symptoms are similar to those of its relative S. sclerotiorum, except that most of the infection continues just above and just below the ground, where the base of the stem is girdled and the plant dies. The sclerotia produced in the mycelium then serve as a source of inoculum for other hosts.
Deep cultivation with soil turning over buries the sclerotia and limits contact between the sclerotia and the bean stems. Some resistant varieties are available, and some progress has been made in using biocontrol agents such as Trichoderma and Gliocladium for use as fungus antagonists.
White mold (Sclerotinia sclerotiorum)
White mold is found in most regions of the world except the tropics, and affects a wide range of host crops. It is also a disease of peas, and much of what is used for peas also applies to beans.
The causative agent is Sclerotinia sclerotiorum.
Infection occurs during periods of leaf moisture and optimum temperature; ascospores are released from apothecia, which in turn are formed from germinating sclerocytes left in the soil from a previous infected crop (Boland and Hall, 1987; Phillips, 1994).
Infection leads to destruction of stem tissue and the formation of dense white mycelium that covers the stems and leaves and infects the pods. Large sclerotia form in the infected tissue. The rate at which the infection spreads is rapid, and widespread loss of crop and bean quality occurs. Cross-infection from harvested fresh bean pods to healthy bean pods in storage or packaging can also occur, further reducing marketability.
Some resistant varieties are known in breeding lines, but there are few immune varieties, and selecting varieties for resistance is difficult because plant architecture can also influence infection (Schwartz and Singh, 2013). Biocontrol agents such as Coniothyrium minitans have been used and have been successful in reducing sclerocytes. The inoculant requires multiple applications to establish populations, and often the time between crops of beans in the field is too long for the agent to survive.
Botrytis pod rot (Botrytis cinerea)
Botrytis pod rot, or grey mold, is ubiquitous and present worldwide, infecting many crops and weeds during periods of high humidity.
The pathogen is Botrytis cinerea.
Infestation occurs on the pod, usually after first infecting the wilted petals, which either adhere to the pod after it wilts or reach the leaf petiole, where the fungus can then infect the stem, causing it to girdle.
Botrytis is also a very important postharvest disease of fresh beans. Damage to the pods leads to rejection of the bean crop for the fresh market or for processing. In dry beans, the pods disintegrate and the seeds may be exposed, resulting in blight, and if the seeds are also infected, the beans will shatter.
Wet conditions are favorable for B. cinerea, and the likelihood of a problem is greater if the weather is wet or if watering is excessive during flowering and pod setting, which allows the petals to remain attached to the ends of the pods. A fungicide program can be used, but in many cases the fungus has developed resistance to the commonly used active ingredients.
Anthracnose (Colletotrichum lindemuthianum)
Anthracnose is distributed throughout the world, but is more common in temperate and subtropical areas than in the tropics. It is found in North and South America, as well as in Europe, Africa, Australia and Asia. It is one of the most important diseases because it causes significant yield loss and damage from pod spoilage. The disease is seed-borne, and once spores appear in warm, humid conditions, the spores spread very quickly by rain splashes to surrounding plants. The disease is especially harmful during the phase of sprouting and fruit formation.
Pathogen: Colletotrichum lindemuthianum fungus (Sace, et Magn.) Br. et Cav.
Symptoms of infestation are very characteristic: black or brown fringed leaf lesions appear first, running along the leaf veins, as well as a blight effect. The diseased part of the tissue often falls out, forming so-called “shoots”. Later, the pods become infected, on which deep round brownish-red merging indented lesions, black in the center, form. In the recesses of the spots, especially in wet weather, whitish-orange or pink pads of conidial sporulation of the fungus form. Conidia are colorless, oblong-cylindrical with rounded ends. The fungus infects the seeds through the pods, on which the same spots are formed as on the pods. The disease appears as brown-red spots on seedpods, with light-colored spots in the center. On stems and petioles, dash-shaped, brown spots appear at first, later turning into ulcers. In wet weather, reddish pads appear in the central part of the affected tissue, which are spores of the fungus.
The fungus is preserved by mycelium in diseased plant debris and infected seeds. The disease is transmitted from plant to plant by raindrops. Optimum temperature for anthracnose is about -20°C. Incubation period is 3-7 days.
Some varieties are resistant to most races, but the pathogenicity of the fungus is very diverse. Seed coat infestation can be controlled by fungicide treatment of seeds, but although fungicides can be applied by leafroll, prevention by using healthy seeds produced under drought conditions is the most effective control measure.
Source: commons.wikimedia.org©Howard F. Schwartz, Colorado State University, Bugwood.org (CC BY 3.0)
Bean rust (Uromyces appendiculatus)
Bean rust, English Bean rust, is found all over the world, but is most common in tropical and subtropical areas. In Latin America, it is most severe in Brazil, the Caribbean, Central America and Mexico, as well as in Africa. It rarely occurs in arid climates, only with irrigation. Rust affects yield and pod quality for both the fresh vegetable market and dried bean production and can reduce dried bean yields by up to 30% through defoliation or reduction of leaf area.
Pathogen: obligate fungus Uromyces appendiculatus (probable syn. Uromices phaseoli (Schrot.)).
When pods become infected, the disease can cause deep, dark sores on the surface, making them unfit for sale in fresh or processed foods. Symptoms first appear as small, round rust-colored spots surrounded by a yellow halo. The pustules develop and produce orange-brown spores that are transferred to surrounding leaves and plants by rain splashes or overhead sprinklers. Later, the spots become larger and the spores turn black.
The pathogen persists as teliospores on plant debris. Mycelium on rhizomes of thrush. In spring, teliospores germinate and form basidia with basidiospores that infect beans and beans. In mixed-farm fungi, the basidiospores infect the thistle, on which the eccidial stage develops, and then the eccidiospores infect the main host.
There are a number of fungicides that are more effective when applied early in disease development. The most effective control of bean rust is varietal resistance. Stable resistance is difficult because the pathogenic variability of the fungus is very large. Although most varieties are resistant to several races of rust, only a few are resistant to most local races. Many rust-resistant genes are present in common bean, and some have been used to develop rust-resistant germplasm and varieties (Park et al., 2004). Significant progress has been made in the United States in breeding beans with multiple resistance genes.
Source: commons.wikimedia.org©Jerzy Opioła (CC BY-SA 4.0)
Bacterial diseases
In all cases of bacterial bean diseases, the primary source of infection is seed, so strict phytosanitary procedures should be implemented in bean seed production areas. In arid areas, seed crops should be inspected during production and checked for the presence of bacterial pathogens. In some situations, seed treatment with streptomycin is used to provide surface sterilization, but it is not available in all countries.
Halo blight (Pseudomonas syringae)
Pseudomonas syringae is the most common bacterial seedborne bean disease of temperate climates.
The causative agent is the bacterium Pseudomonas syringae pv. phaseolicola.
Symptoms of the disease on the leaves consist of small, angular, necrotic fatty spots that are surrounded by a chlorotic patch of tissue. Later, depressed, watery oily spots appear on the pods, which deepen into the pod wall until the developing seeds become infected. Because the disease spreads easily during rains or by watering overhead, the effect on the crop usually appears as small, discrete spots that spread quickly in the direction of the prevailing wind. Yield loss is caused by defoliation and plant death, and pod damage can result in culling of the crop when fresh beans are harvested.
Infected seeds or crop residues are the source of infection, but under normal crop rotation, the bacterium does not survive in the soil for more than 1 year.
No effective means of chemical control exists, so the only means of preventing the disease is seed health improvement.
Common blight (Xanthomonas campestris)
Common blight is a bacterial blight that affects leaves and pods and is considered a major problem in most tropical and semi-tropical bean-growing areas.
The causative agent is Xanthomonas campestris pv. phaseoli.
Symptoms of leaf infestation appear as water-soaked spots that expand and the surrounding tissue becomes necrotic and is bordered by an area of lemon-colored tissue. Eventually, the leaves take on a scalded appearance. Pod lesions are sunken and brown in color.
The disease can be very destructive during periods of warm, wet weather when yield and bean quality losses occur.
Bacterial wilt (Curtobacterium flaccumfasciens)
Bacterial wilt causes bean plants to wilt during periods of moisture deficiency. It has been reported in the USA, Tunisia, Australia, Greece, Canada and Colombia as well as other production regions.
The causative agent is Curtobacterium flaccumfasciens.
Viruses
Schwartz et al. (2005) described a number of viral diseases associated with Phaseolus bean, but the most common serious viruses are bean mosaic virus (BCMV), bean curly-top virus (BCTV), yellow bean mosaic virus (BYMV), and cucumber mosaic virus (CMV).
Bean common mosaic virus (BCMV)
Bean common mosaic virus (BCMV) is found worldwide, and in areas where susceptible varieties are grown, the disease can cause severe yield losses, poor pod set and pod development. The virus can survive in host weeds and, to a small extent, in infected seeds. The virus is then transmitted by aphid vectors, including Acyrthosiphon pisum, Macrosiphon euphorbiaea, Myzus persicae, and Aphis fabae. Irregularly shaped pale and dark areas appear on the surface of the three-leaf bean, most often the leaves curl downward and may grow longer than the rest. Some beans may show brown discoloration on leaf veins and stems. Most commercial varieties are resistant to BCMV, but dried bean varieties may be more susceptible. Effective aphid control and planting before aphid activity begins will also reduce the risk of infection.
Bean curly top virus (BCTV)
Bean curly top virus (BCTV) is found in the western United States and British Columbia. The seedlings develop as dwarf plants, with severe wrinkling and downward curling of the leaves. Plants are severely dwarfed and wispy. Leaves become brittle and flowers may wilt. The virus has several hosts, which are perennial or winter annual plants, such as Russian thistle or bramble (Salsola tragu), mustard, and sugar beet. The virus is carried by the beet leaf beetle (Circulifer tenullus), and warm, dry weather early in the season promotes migration of the virus from wintering leaf beetle hosts to newly emerged beans. There are a number of resistant varieties because treatment against leafminer is usually too late to be effective.
Bean yellow mosaic virus (BYMV)
Bean yellow mosaic virus (BYMV) develops in beans any time before flowering. Leaves may be shriveled and pointed with some vein brightening. Leaves may droop, yellow mottling may appear on older leaves, and plants may be stunted. BYMV virus is widespread throughout the world and has several legume and nonlegume hosts. The virus is transmitted by aphids, and infection can occur on individual plants as well as groups of plants. Depending on the degree of infestation, yields may be reduced and pods may be damaged or incomplete. BYMV is also known as Phaseolus virus 2 and can be transmitted by seeds of some legumes, including V. faba. Several aphid vectors can transmit the virus between beans from wintering hosts. The main vector is Acyrthosiphon pisum; the virus is resistant and has a wide range of hosts, including peas, clover, alfalfa, gladiolus, freesia, lupine, soybeans, and wild legumes. There are some resistant dry bean varieties, but early aphid control on flowering crops is the most effective way to prevent widespread infestation.
Cucumber mosaic virus (CMV)
Cucumber mosaic virus (CMV) is found in many countries, including Europe and the Far East. Whole bean fields are known to be affected in the United States, but economic losses depend on the timing of infection. Late infestation decreases pod quality.
Symptoms include narrowing and sharpening of the leaves with mosaic developing later. Other symptoms include curling leaves, green and chlorotic mottling and dark green streaking of the veins. Some strains of CMV can be transmitted by bean seeds, but the disease is easily transmitted by several aphid vectors. The virus has a wide range of weed hosts, including several perennial species.
Healthy seeds are a useful preventative, but aphid control is more important. Some commercial varieties are resistant to CMV, and work is underway to develop new varieties that are resistant to this virus.
Sources
Modern technologies in vegetable production / Dr. A.A. Autko [etc.]; edited by A.A. Autko. – National Academy of Sciences of Belarus, Institute of Vegetable Growing. – Minsk : Belarus. nauvuka, 2012. – 490 p., [16] l. ill.
Peas and beans. Crop production science in horticulture / Antony J. Biddle. 2017. UK.
Diseases of peas
Main pathogens of pea diseases
The causative agents of pea diseases:
- Aphanomyces euteiches;
- Colletotrichum pisi;
- Ascochyta pisi; A. pinodella;
- Mycosphaerella pinodes;
- Pseudomonas syringae pv. pisi;
- Thielaviopsis basicola;
- Botrytis cinerea;
- Peronospora pisi, P. viciae (false powdery mildew);
- Fusarium oxysporum f. pisi, other races of F. oxysporum;
- Fusarium solani f. sp. pisi;
- Phoma medicaginis var. pinodella;
- Erysiphe polygoni, other Erysiphe spp. species (powdery mildew);
- Pythium ultimum, other species of Pythium spp;
- Uromyces pisi, U, fabae, U, trifolii;
- Sclerotinia sclerotiorum;
- Septoria pisi.
Viruses:
- Bean Leaf Roll Virus;
- Bean Yellow Mosaic Virus (BYMV);
- Pea Enation Mosaic Virus;
- Pea Streak Virus;
- Pea Stunt Virus;
- Pea Seed Borne Virus;
- Pea Early Browning Virus;
- Pea Top Yellow Virus;
- Common Pea Mosaic Virus;
- Cucumber Mosaic Virus (CMV).
Root rot
Root rot, Foot rot diseases, is the most damaging complex of soil pathogens of root infection and includes several fungi that can cause severe sprouting or root rot of peas in almost all traditional pea growing areas of the world.
The impact on the crop has been described as pea root rot (Biddle, 1983). The fungus accumulates in the soil as a result of frequent sowing, and because the rate of decay of dormant spores is slower than the return time of peas, the soil population increases to the point where the crop becomes heavily infested.
In the United Kingdom, three major organisms are involved in the root rot complex, each of which can infect individually or together. Several Fusarium species may be present, the main one being Fusarium solani f. sp. pisi. The pathogen itself penetrates the roots early in the growing season; during its development, the roots are destroyed and the vascular system is blocked by toxins produced by the fungus. This causes premature senescence and subsequent death.
The second pathogen is Didymella pinodella (syn. Phoma medicaginis var. pinodella) (Chen and Cai, 2015), an ascomycete fungus that can be transmitted through soil, producing thick-walled chlamydospores, or through seeds when infection develops on leaves and pods. Initially, D. pinodella infection causes girdling at the base of the stem, which turns black and eventually collapses. After initial infection, leaf and pod spotting may occur on neighboring plants, and pods and seeds become infected during periods of wet and rainy weather.
The third pathogen is Aphanomyces euteiches, which causes root rot. It is a phycomycete fungus that produces zoospores that are motile in moist soil conditions. Once infected, the root bark is destroyed and peels away from the vascular sheath. The oospores produced in the bark can remain in the soil for many years. Moist soil conditions are favorable for it, and it is a major pathogen in light soils with finer texture in the Paris Basin in France, where large losses of peas from root rot have often occurred with frequent farming.
There are no universal control measures for these soil fungi, and the only effective means of controlling them is to avoid cultivating peas more frequently than once every 5 years (Biddle, 1983). In the United Kingdom, where serious problems arose in the 1970s, the interval between pea crops was extended to 6 or even 7 years to prevent the development of damaging fungal populations.
In Great Britain, a test for predicting soil-borne diseases was developed and used as a guide to identify fields with high pathogen populations (Biddle et al., 1988). In France and Scandinavia, a similar method is used to select fields with high levels of A. euteiches. Much work is being done to develop varieties with resistance to these pathogens, but no varieties with combined resistance to all have been developed because of the complexity of the problem (Ali et al., 1994), although work is in progress in Europe with a research cooperative to identify resistance to Fusarium and drought stresses.
Fusarium root rot
The causative agents are imperfect fungi of the genus Fusarium spp.
The disease manifestation is different: plants are affected from the phase of seedlings to seed formation. On seedlings, Fusarium root rot appears as browning of the cotyledon and root tip of seedlings. The seedlings turn yellow, overstemming and root rot appear, and they die. Later, the roots and root part of the stem are affected, reddening of the main and lateral roots is revealed. Longitudinal cracks appear on the underground part of the stem, as a result of which the roots die off.
In fusarium wilt, fungi release toxins and clog blood vessels of the conductive system (tracheomycosis type of lesion). The fungus sometimes reaches the upper parts of the plant via the vascular conductive system, resulting in yellowing, wilting, desiccation, and death. Transverse section of diseased stems and roots shows fulvous vessels. In humid conditions, single plaque of conidial sporonose fungus, macro- and microconidia, appears on the affected areas. The disease is harmful under conditions of wet spring and dry hot summer with insufficient moisture in the soil. But the disease is particularly strong during flowering and the beginning of fruit formation. Increased soil acidity also contributes to the progression of fusariosis. Sources of infection are infected plant residues in the soil and seeds. If beans and seeds are infected, the infection can persist in the seed.
Leaf and pod spot (Ascochyta)
Leaf and pod spot, or Ascochyta, is a widespread disease that affects leguminous vegetable crops.
There are three closely related fungi that make up the Ascochyta pisi, Mycosphaerella pinodes and Didymella pinodella (Phoma medicaginis var. pinodella) disease complex on peas, all of which can cause leaf and pod spot in peas. In addition to these pathogens, two types of ascochytosis can appear on peas: light spotted (Ascochyta pisi (Lib.)) and dark spotted (Ascochyta pinocles (Veg. Et Bl.) Jones). All are seed-borne and can survive on plant debris; M. pinodes and D. pinodella are also soil-borne. The symptoms of each are different, but A. pisi causes a more characteristic type of leaf and pod spotting and is more common worldwide.
Seedlings derived from seeds infected with A. pisi show symptoms soon after emergence, especially if the weather has been wet. Brown or gray depressed lesions develop on the stem, leaves, or stems. As the plant develops, pycnidia form in the center of the lesions, and the release of ascospores occurs when exposed to rain or splashes of water droplets. The spores then infect surrounding plants, eventually forming lesions on the pods, and the deep-seated infection continues to infect developing seeds.
Light-spotted ascochytosis on leaves, stems, and beans appears as large, rounded, yellowish spots surrounded by a brown border with a lighter middle and small pycnidia on them. Affected leaves wither prematurely and stems break. Affected seeds have wrinkled surface with light yellow spots. Such seeds do not sprout, or they produce sick sprouts. Ascochytosis appears as yellow-brown spots on cotyledons and stalks, and some shoots die.
Dark spots, almost black in the center, depressed, irregularly shaped, appear on stalks and beans. Few brown pycnidia, fruiting bodies of the pathogen, are observed in the spot center. Affected stems become crushed, and when beans are infected, their seeds become stubby or are not formed at all.
M. pinodes spreads from infected seeds, but can also be infected from soil plant residues or from chlamydospores that infect the stem base, resulting in stem girdling and subsequent leaf and pod spotting with smaller, more purplish lesions that are not as deep as those of A. pisi. D. pinodella is most commonly infected from soil, where thick-walled chlamydospores can remain viable for several years. The disease primarily causes foot rot, but leaf and pod spotting can occur later in the season if the soil is moist, with frequent rainfall and warm temperatures.
Seeds are the primary source of primary infection, and using healthy seeds is the only way to avoid A. pisi infection. Since both M. pinodes and D. pinodella are soil-borne, a long rotation in which peas are not grown too often will delay the accumulation of soil-borne populations. Seed crops grown in arid areas are less prone to infestation, but in other temperate areas the risk of disease is higher where summer rainfall is more erratic. Seed fungicide treatments are effective in controlling most seed-borne Ascochyta, but the use of heavily infested seeds, even with seed treatments, does not always result in complete healthy seedlings.
Resistance to A. pisi is currently being studied, but because of the range of pathotypes, it is difficult to develop varieties with complete resistance (Tivoli et al., 2006; Muehlbauer and Chen, 2007).
Powdery mildew (Erysiphe pisi)
Powdery mildew, or true powdery mildew, or Erysiphos. The causative agent is the fungus Erysiphe pisi (syn. Erysiphe communis Grev. pisi (Dietrich.)) – A very common pathogen in all areas where peas are grown. Severe infection reduces pod weight and yield, and seeds cannot reach their full potential in infected pods.
The disease is favored by warm daytime temperatures and cool, wet nights. Strong powdery mildew development is seen in dry summers. Late-seeded peas are more susceptible to infection, and it is on these crops that it appears strongest. The incubation period under favorable conditions is 4-5 days. The fungus spores in dry air and in bright light better mature and germinate, and the plant is less resistant to disease.
The main type of infestation is the formation of an irregular white powdery plaque on leaves and stems, consisting of conidial sporulation fungus. Disease development begins on lower leaves and stem base, but then spreads rapidly to all parts of the plant and beans. By the end of vegetation, fruiting bodies, cleistothecia, are formed on the affected tissues, which remain on plant debris. In spring, the cleistothecia open, and the sacs expel sacospores that infect young plants. The fungus, penetrating inside the leaf, causes tissue death.
Ripening of peas grown for dry picking is delayed, and peas grown for the fresh market turn out to be spoiled and unfit for sale.
The fungus overwinters on crop residues and alternative host plants such as vetiver and other wild legumes.
Variety resistance to powdery mildew is mainly transmitted by three recessive genes, er-1, er-2, and er-3, with er-1 being most commonly used by breeders (Fondevilla and Rubiales, 2012). Several commercially available varieties are completely resistant to this disease in the field, and breeders continue to work to expand their numbers.
Very few fungicides are available for powdery mildew control, but regular spraying with elemental sulfur can provide some protection.
Pea downy mildew (Peronospora viciae)
Pea downy mildew is common in temperate pea-growing countries, especially in Northern Europe, Scandinavia, New Zealand, and the northern and midwestern United States, although the disease is rare in the drier states.
The causative agent is the fungus Peronospora viciae.
The disease causes significant plant losses early in the season when weather conditions are more favorable for infection because the fungus prefers moist, cool conditions. Later in the season, the infection weakens the plant and reduces the number of pods and seeds. The pods become damaged and unsuitable for sale in the fresh market, and peas for processing are often damaged and incomplete. Oospores form in infested tissue and remain viable for many years after returning to the soil. Dense crops of peas are a major cause of severe infection.
Taylor et al. (1989) reported that there are 11 races or pathotypes of P. viciae in the United Kingdom, and most fields with a history of the disease contain mixtures of them. Therefore, selection for complete resistance has not been achieved, but several varieties show different levels of resistance in the field to infection, and on this basis, varieties in the UK are classified according to their relative resistance. As for peas, very few varieties show good resistance, and all are regularly treated with seed fungicide preparations. Before the introduction of acyl-aniline fungicides, which are active against Peronospora spp., many early-ripening pea varieties were severely affected by the disease and yield losses were greatly reduced, making growing early varieties virtually unviable. In contrast, most combination pea varieties grown in the United Kingdom and Europe have good field resistance and are grown without seed treatment.
White mold (Sclerotinia sclerotiorum)
Sclerotinia sclerotiorum has a very wide host range and can infect most broadleaf (dicotyledonous) crops, including vegetables, potatoes, flax (Linum spp.) and oilseed rape in most regions of the world. The infection is common in some areas where susceptible crops are present in the crop rotation and is found in many regions of the world except the warm, humid tropics.
The disease spreads rapidly in warm, humid weather and causes stem, leaf, pod, and pea rot.
The infection is characterized by the appearance of wet rot followed quickly by the formation of dense white cotton-like mycelium. Infected stems appear discolored, and sclerotia develop inside the stems and pods.
Once infection is established, the sclerotia return to the soil at harvest time, where they may remain viable for 5 years or more. Under suitable conditions, the sclerotia produce apothecia on the soil surface, which release ascospores that germinate on fresh green leaves, stems, or wilted flower petals; the pathogen then becomes virulent and affects the rest of the plant.
Control of the disease is based on crop rotation and refusal to grow peas in close proximity or in close rotation with previously infected plants. Most pea varieties are susceptible, although early crops can avoid infection because it usually occurs late in the season when temperatures rise. Modeling of outbreaks based on oilseed rape petal sampling and local meteorological data has been done in the UK and elsewhere for oilseed rape, and similar modeling has been done for lettuce (Clarkson et al., 2014). For peas, the susceptibility time to infection is very short, and models tend to indicate a wide window of opportunity for treatment. Using a predictive model as a decision support system for peas has been studied in the UK, but peas are only susceptible to infection during the flowering stage, which is very short (HDC, 2013).
Source: commons.wikimedia.org©Rasbak (CC BY-SA 3.0)
Pea rust (Uromyces pisi)
Pea rust affects many legumes.
Pathogen: fungus Uromices pisi (Schrot.), which also affects chinna, is an obligate parasite characterized by local type of disease manifestation. As an intermediate host, the spring (ecidial) stage of the pathogen develops in the form of cup-shaped receptacles on the underside of leaves. The ecidiospores are wind-borne on peas and other legumes.
Rust usually appears in mid-summer. Orange-brownish, convex, uredopustules form on leaves, stems, and beans, often powdering, thus infecting plants during the growing season. By the end of summer, pustules become dark, almost black, in which ellipsoidal or obovoid winter spores (teliospores) with thick shell are formed. Affected leaves turn yellow and dry out.
The pathogen persists as teliospores on plant debris. Mycelium of fungi overwinters on rhizomes of thrush. In spring, the teliospores germinate, forming basidia with basidiospores that infect beans and beans. In mixed-farm fungi, the basidiospores infect the thrush, on which the eccidial stage develops, and then the eccidiospores infect the main host.
Bacteriosis (Pseudomonas syringae)
Bacteriosis, Pea bacterial blight, can be important in crops sown in the fall or crops grown under irrigation. In Europe and New Zealand, where fall sowing is common in some areas, the disease can be very severe and yield losses are not uncommon. In dry conditions, the disease is not severe enough to cause losses; on crops sown in the spring, significant damage is rare unless there has been damage from frost or hail.
Pathogen: bacterium Pseudomonas syringae pv. pisi (erroneously “Pseudomonas pisi fungus (Bergey ct all)”; Autko).
The pathogen is seed-borne, and symptoms can occur at any time during the growing season, especially after physical or mechanical damage to pea leaves. Bacteria enter plant tissues through stomata or mechanical damage, spreading through the intercellular spaces, destroying cells. Infection, entering the vessels, causes wilting of leaves and the entire plant. Small, dark green, watery spots initially appear on leaves and beans, which then increase in size. As the affected tissues dry out, the spots turn reddish brown. The bacteria can penetrate the pedicels and cause flower death. Young beans affected by bacteriosis shrivel and dry out. Severely infested beans exhibit a slimy mass or sores with “fatty” spots. Infestation of seeds can occur during their ripening.
The main source of bacteriosis is infected seeds and postharvest crop residues.
There are seven races of bacterial infestation in peas. In the United Kingdom, race 2 is most common on spring varieties, and races 4 and 6 occur on winter peas. In the U.S., race 4 appears to be most common on spring peas.
No chemical means of control exist, and use of healthy seeds is the most effective means of preventing infestation. The bacterium does not survive on crop residues for more than 1 year. There are no varieties resistant to all seven races, but several varieties are resistant to races 2 and 4.
Fusarium vascular wilts (Fusarium oxysporum)
Several races of Fusarium oxysporum f. sp. pisi are found in many countries where peas are grown. The disease caused by F. oxysporum, often results in vascular wilt over large areas during flowering and seed set.
The first race of Fusarium wilt is characterized by stunted plant growth as well as discoloration of the leaves, which first take on a grayish hue, then shrivel up and cause the plant to die. Race 2 is known as close wilt, and plants are affected either individually or in scattered patches throughout the field. Roots often die off, causing the plant to wilt and age prematurely. Race 6 has been reported in the United States and Scandinavia and probably occurs occasionally in Europe and Australasia. Symptoms are very similar to those caused by the soil root fungus. Other races, including race 5, have been described in the United States (Kraft, 1994), but the symptoms are very similar to those of other races, with race 5 symptoms similar to those of race 1.
Pea wilt became a serious problem in the U.S. in the early 20th century, and in most years many crops were lost in Wisconsin. The disease was first described by Linford (1928), but was later isolated as race 1 F. oxysporum f. sp. pisi in 1935. Only when breeders discovered resistance to wilt (Wade, 1929) did the disease become manageable, and many varieties with resistance to race 1 have now been bred, and some are also resistant to other races.
In the UK, all registered new varieties are tested for resistance to race 1, and this information can be obtained from breeders or from the recommended pea variety list (PGRO, 2015). Crop rotation is ineffective when the disease is present in the soil, but a rotation that includes peas no more than once every 5 years will help prevent disease development.
Viruses
Of the important pea viruses in Europe, the United States and Australasia, four aphid-borne viruses can cause the most serious damage or loss of crop or product quality. The pea aphid (Acyrthosiphon pisum) is a vector of several viruses, including pea enation mosaic virus (PEMV), pea apical yellowing virus (PTYV), alfalfa mosaic virus (pea stripe) and pea seed-borne mosaic virus (PSbMV), which is also transmitted by seeds.
The most significant damage from PEMV and PTYV results from early invasions of pea aphids, which bring these diseases into the crop from overwintering hosts. PEMV has a range of overwintering hosts that includes wild and cultivated legumes such as forage beans (Vicia faba), chickpeas (Cicer arietinum), sweet (chickpea) (Lathyrus oderatus), lentils (Lens culinaris), Medicago arabica and seed vetch (Vicia sativa).
PTYV is also known as bean leafroll virus and has wild hosts such as clover and creeper, and on alfalfa (alfalfa) and winter V. faba. PSbMV is mainly seed-borne and is only transmitted between neighboring peas during aphid movement into the crop. In some cases, it has been suggested that forage cereal aphids may also transmit PSbMV from an infected seedling to the rest of the surrounding crop.
Several cultivars are resistant to one or both PEMV and PTYV, and a small number of cultivars have also been bred for resistance to PSbMV. A possible source of resistance is a difference in the ability of the virus to penetrate the developing seed (Roberts et al., 2003). In general, effective aphid control is necessary to avoid infection, but in the case of PSbMV, only the use of healthy seeds ensures that the disease is not present. The main symptom of PSbMV is stunting of the plants, and the seedpods often have spots with a white border that can be compared to the marks on a tennis ball. Affected peas can cause crop rejection by processors of frozen peas, and in the mid-1980s, seed stocks of the variety petits pois, which was widely used in Great Britain and Europe, were severely infected. In 1987, a research program to detect the presence of the virus in seed was initiated, which led to a widespread testing program using an ELISA-based seed test to identify seed stocks carrying the infection. This program has been effective and has produced healthy seeds of this variety, which remains one of the most important petits pois cultivars grown in Europe and the United States.
In Europe, a nematode-transmitted virus, Pea Early Brown Spot Virus (PEBV), occurs in some seasons. Free-living nematodes, including the vector Trichodorus sp., are often found in free-draining sandy soil and graze on pea roots during periods of high soil moisture in spring. The virus develops in peas, leading to characteristic leaf mosaic, purple stems, stunting and necrosis of the main shoot.
The disease can also be transmitted through seed. Seed health treatments can be effective in reducing the risk of introducing the virus to other areas where trichodorid nematodes are present. A detailed review of the virus was written by Boulton (1996).
Sources
Modern technologies in vegetable production / Dr. A.A. Autko [etc.]; edited by A.A. Autko. – National Academy of Sciences of Belarus, Institute of Vegetable Growing. – Minsk : Belarus. nauvuka, 2012. – 490 p., [16] l. ill.
Peas and beans. Crop production science in horticulture / Antony J. Biddle. 2017. UK.
Maral root
Leuzea safflower-like (Rhaponticum carthamoides, also “maral root”) is a medicinal plant.
Source: commons.wikimedia.org©Meneerke bloem (CC BY-SA 3.0)
Economic importance
The rhizomes and roots of Leuzea safflower contain alkaloids, tannins, essential oils, resins and mineral salts, ascorbic acid. Roots and rhizomes are used to obtain extracts and tinctures that have a stimulant in physical, mental and mental overwork. They can be used to increase efficiency, appetite, sexual
potency, etc.
Leuzea safflower is a promising fodder plant for the forest-meadow and forest-steppe zones of Russia. The yield of green mass reaches 30-35 t/ha. The green mass is suitable for the preparation of silage, haylage and vitamin-grass flour. Plants are readily eaten by farm animals in their pure form and in mixtures with other herbs. In terms of protein content, Leuzea safflower is not inferior to legumes. Due to the high content of sugars, it is suitable for ensiling both in pure form and in mixtures with various fodder crops, such as corn, annual grasses.
100 kg of green mass of safflower leuzea correspond to 15 feed units and contain 2.1 kg of digestible protein; 1 feed unit accounts for 140 g of protein. 100 kg of silage correspond to 16.5 feed units and 2.1 kg of digestible protein; 1 feed unit accounts for 127 g.
The inclusion of leuzea feed in the diet has a positive effect on the reproductive ability of animals.
Good honey plant.
Crop history
Leuzea safflower has long been known in Mongolia. Until now, it is believed that this plant can cure 14 diseases and give a person strength up to 100 years.
Habitats
Plants of the genus Leuzea are distributed mainly in the Northern Hemisphere.
In Russia, the range of Leuzea species mainly extends to the mountains of Altai, Kuznetsk Alatau, Sayan, etc.
Botanical description
Leuzea safflower-like (russian), or safflower-shaped raponticum (Raponticum carthamoides Willd) is a perennial rhizomatous plant of the Asteraceae family.
The genus Leuzea includes 17 species, 14 of them grow in Russia.
The tap root, gradually thickening, has numerous branches, penetrates the soil to a depth of 80 cm, forms a powerful branching rhizome.
Stem erect, irregularly rounded, hollow, slightly branched, slightly leafy. Plant height 130-180 cm.
Leaves sessile, in the lower part of the plants 70-90 cm long, 15-25 cm wide, in the upper part much smaller, deeply pinnately dissected, on long petioles.
The inflorescence is a dense, rounded basket, 5-8 cm in diameter. The flowers are bisexual, violet-lilac or pinkish.
The fruit is a purple-brown tetrahedral achene. Weight of 1000 pieces – 15-18 g.
Biological features
Leuzea safflower-like – a plant of winter type of development. In the first year of life, it forms a powerful rosette of leaves.
In the second and subsequent years, plant growth begins immediately after the snow melts. Flowering occurs in late May – early June. Fruiting occurs from the second year of life. After fruit ripening, generative shoots die off completely 1-1.5 months before the end of the growing season.
Leuzea begins to produce the largest yields of green mass from the third year of life.
It tolerates double use well. The proportion of leaves by the stage of cutting maturity reaches 60-70% of the total above-ground phytomass.
Leuzea safflower-like is a light-loving plant, therefore, sowing under the cover of other crops is not carried out.
Frost-resistant. Seedlings are able to tolerate early spring frosts down to -4 °C.
Leuzea is not very demanding on moisture, therefore it can be cultivated in the conditions of the forest-steppe zone. However, it does not tolerate waterlogging of the soil and prolonged flooding.
Highly fertile sandy and loamy, gray forest and chernozem, well-aerated soils with a slightly acidic reaction (pH 5.6-6.0) are considered optimal.
Agrotechnology
For the formation of 10 tons of green mass, the safflower-like leuzea removes 35.7-50.0 kg of nitrogen from the soil; 5.9-12.0 kg of phosphorus; 48.7-55.0 kg of potassium, 30.5-37.3 kg of calcium.
Leuzea is usually grown in non-rotational areas.
The best predecessors are annual grasses, tilled and leguminous crops.
When laying a plantation, 50-60 t/ha of organic fertilizers and lime are applied to the soil, the application rate of which is calculated from the total hydrolytic acidity.
After plowing, the field is cultivated.
In the case of late autumn sowing, the treatment is carried out with an РВК-3 unit. Sowing Sowing can be done in the fall 1-2 weeks before the onset of permanent frosts, but it is best to sow in the spring. Vegetable seeders with row spacing of 60-70 cm can be used for sowing. Sowing depth is 2-3 cm. Seeding rate is 6-10 kg/ha.
In the first year of plant life , 2-4 inter-row treatments are carried out for weed control , if necessary, herbicides are applied.
Mowing of the safflower-like leuzea in the first year of life is usually not carried out so as not to weaken the plants and not worsen overwintering.
In the second and subsequent years, inter-row cultivation is carried out on the plantation in early spring with simultaneous top dressing. The fertilizer application rate for top dressing is N45-60P45-60K45-60.
After the first mowing, a second inter-row processing is done with the simultaneous application of P20-30K20-30. Every 2-3 years it is recommended to apply rotted manure on the plantation at the rate of 15-20 t/ha.
Harvesting
When cultivating safflower-like leuzea to obtain vitamin-herbal flour, they start harvesting in the budding phase, for silage – in the flowering phase. To protect the bees, harvesting is carried out early in the morning and late in the evening.
Leuzea safflower-like allows two-fold mowing every year, while depletion of plants is not observed.
The second mowing is usually done in late August – early September.
For use any silo harvesters.
Leuzea seeds can be obtained from ordinary forage crops, starting from the third year of life. Harvesting for seeds begins when 70% of the inflorescences turn brown. For this, semi-mounted sorghum harvesters can be used. Cut inflorescences are dried and threshed on a current. After harvesting the inflorescences, the remaining mass is suitable for livestock feed.
Sources
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Melissa officinalis
Lemon balm (Melissa officinalis) is a medicinal, essential oil and vegetable plant.
Source: commons.wikimedia.org©H. Zell (CC BY-SA 3.0)
Navigation
- Medicinal and alkaloid plants
- Tobacco
- Strong tobacco
- Common hop
- Melissa officinalis (Русская версия)
Economic importance
Melissa officinalis is widely used as a medicinal, essential oil and vegetable plant. Young greens are used as a seasoning and for the preparation of tonic infusions. Due to the volatility of its delicate lemon flavor, lemon balm is added to ready meals. When dried, lemon balm gradually loses its aroma even in tightly closed containers.
The leaves contain essential oil, which is used in medicine, perfumery and the production of alcoholic beverages.
The aerial vegetative part (“grass”) has an analgesic and antispasmodic effect. Melissa infusions serve as an appetite stimulant, normalize the functioning of the gastrointestinal tract, relieve fatigue, have a calming and tonic effect on the nervous system, and help with insomnia and migraines. A decoction is used to rinse the mouth with inflammation of the gums, for the treatment of skin diseases.
For medicinal purposes, use the leaves collected in the budding phase. During this period, they contain up to 0.3% essential oil, as well as carotene and tannins. The seeds contain up to 20% fatty oil.
Crop history
Melissa officinalis has been known as a medicinal plant for over 2,000 years.
The homeland is the Mediterranean.
Habitats
Currently, lemon balm is grown in small areas in some countries of Europe, Asia, and also in the USA.
Melissa has been cultivated in Russia since the middle of the 20th century.
Botanical description
Lemon balm (Melissa officinalis L.) is a perennial herb belonging to the Lamiaceae family.
The root system is in the form of a strongly branched rhizome.
The stem is straight, tetrahedral, branched. Plant height reaches 1.0 m. Creeping in the lower and side shoots.
Leaves ovate, petiolate, light green.
The flowers are small, sessile, yellowish, pink or whitish. The inflorescence is a complex umbrella, located in the axils of the upper leaves.
The fruit consists of four nuts, brown or almost black. Weight of 1000 pieces 0.5-0.7 g.
Biological features
Melissa officinalis is a thermophilic and light-loving culture. Shading leads to a decrease in the content of essential oil in the leaves.
For normal growth and development, plants need sufficient moisture, but lemon balm does not tolerate excess water.
Prefers fertile, light-textured soils.
It has poor winter hardiness, therefore, in the northern regions it is grown only as an annual crop.
Agrotechnology
The best predecessors of lemon balm are perennial herbs , vegetables, winter grains and legumes .
Lemon balm plantations are usually planted for 3-5 years.
Soil preparation includes:
- stubble peeling;
- autumn plowing;
- early spring harrowing;
- deep preplant cultivation to a depth of 12-15 cm.
It is recommended to apply organic (20-30 t/ha) and mineral fertilizers for autumn plowing. In the second and subsequent years of plantation use, two fertilizing with nitrogen and phosphorus fertilizers is carried out during the growing season . Top dressing is given in early spring and after the first mowing.
Melissa officinalis is propagated by seed, seedling and vegetative methods. For vegetative propagation, parts of old bushes, layering and rhizomes are used. The layout of plants 60-70 × 30 cm.
Landing care includes:
- 3-4 inter-row loosening;
- 1-2 weeding;
- top dressing;
- 3-4 waterings.
Irrigation rate is 500-600 m3/ha. Watering is carried out in dry weather.
Cleaning and drying
During the summer, lemon balm is mowed 2-3 times. The yield of green mass in this case reaches 20-25 t/ha.
The selection of essential oil is carried out by steam distillation of freshly harvested raw materials. The yield of essential oil is usually 30-35 kg/ha.
To harvest lemon balm as a raw material for the food industry, the green mass is dried in the shade under sheds or in dryers at a temperature not exceeding +35 °C.
Harvesting of lemon balm for seeds is carried out in single-phase or two-phase methods. The yield of seeds is usually 200-300 kg/ha.
Sources
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Common hop
Common hop (Humulus lupulus) is a medicinal plant.
Source: flickr.com©Matt Lavin (CC BY-SA 2.0)
Economic importance
Common hop has long been used in many peoples of the world for various purposes.
For brewing purposes, this plant is cultivated on special plantations in many countries, for example, in the USA, England, Germany, Russia. The main raw materials are “cones”, which contain 16-26% bitter resinous and 3% tannins, as well as 0.4% essential oils.
In limited quantities, the “cones” of common hops are used for baking some types of bread. The young shoots are sometimes used for culinary purposes.
Common hop is important as a medicinal plant. It has properties that improve appetite and digestion, and is used in the treatment of kidneys and bladder, irritability and insomnia, gout, rheumatism, etc.
Crop history
The first mention of the use of common hop for medicinal purposes refers to the Arabs and dates back to the VIII century. AD Around the same time, it began to be grown in Europe.
Cultivation areas and yield
Currently, the area of cultivation of cultivated and wild hops occupies a large territory in Europe and Asia Minor.
In Russia, hops are distributed almost everywhere in the European and Asian parts of the country. Hop is considered a plant of Russian forests and does not belong to specially protected species. In forests of different types, it is usually found scattered – one or several plants.
Botanical description
Hop (Humulus lupulus L.) is a perennial herbaceous vine belonging to the Cannabinaceae family.
The root system is taproot with horizontal underground rhizomes.
Above-ground shoots can reach 7 m in length.
Leaves opposite, heart-shaped.
Male flowers are small, yellowish-green, located in axillary paniculate inflorescences. Female inflorescences are collected in capitate inflorescences, resembling “cones” in appearance.
The fruit is a nutlet, brown in color.
Flowering in July-August, fruiting in August-September.
Biological features
Hop is a moisture-loving and heat-loving plant.
The sum of temperatures for its development averages about 2600 °C. The optimal average daily temperature is 16-18 °C.
The optimal amount of annual precipitation is 450-650 mm, relative humidity is 70-80%.
Common hop is demanding on soils. It develops well on fertile soils with a slightly acidic reaction. Chernozems, gray forest, light and loamy soils are considered the best. Sandy, carbonate and waterlogged soils are unsuitable.
From the soil, hops absorb 3.5-4 times more nutrients (NPK) than winter wheat.
Hops are considered a plant sensitive to zinc deficiency in the soil.
Agrotechnology
Typically, hops are grown on permanent plantations ranging from 3-4 to 30-40 hectares for 15-20 years. For the growth and development of plants, special trellises up to 7 m high are constructed to support the above-ground part.
Growing hops from seeds is only important in breeding work.
To propagate this culture, a vegetative method is used using cuttings that are cut from the underground parts of the stems. For accelerated reproduction, rhizomes and shoots can also be used.
In some cases, the cultivation of special seedlings in nurseries is practiced.
The planting scheme in commercial hop farms: 2.25 x 1.0 m or 2.5 x 1.2 m. At the same time, the density of plants per 1 ha is 4.4 and 3.3 thousand plants.
Hop care includes:
- pinching;
- tweezing of lateral branches;
- chasing the tops of the bushes.
The main goal of care work is to limit the growth processes of the vegetative organs and enhance the formation of “bumps”.
Cleaning and drying
Harvesting of the “cones” of hops begins at technical ripeness, that is, when the green color changes to a lighter, yellow-green or golden green. In a state of technical ripeness, the “cones” have a strong smell of lupulin.
Cleaning must be carried out quickly, as the browned “bumps” lose quality. During harvesting, the “bumps” break off separately with a petiole no more than 2 cm.
The moisture content of the “cones” at the time of harvesting is about 80%, so they are immediately sent for drying in special hop dryers. During drying, the moisture content of the “cones” is brought to 8-9%, after which they are pressed, packed into a fabric weighing 15-16 kg.
Sources
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Strong tobacco
Strong tobacco (Nicotiana rustica, russian “makhorka”) is an alkaloid plant and industrial crop.
Source: commons.wikimedia.org©Magnus Manske (CC BY-SA 3.0)
- Medicinal and alkaloid plants
- Tobacco
- Strong tobacco (Русская версия)
Economic importance
Strong tobacco is grown for smoking (shag) grits, snuff and chewing tobacco. For smoking purposes, shag is used much less frequently than tobacco .
Dried shag leaves contain 5-15% nicotine, 15-20% organic acids, including 7-14% citric and 3-4% malic acids. The stems of shag plants contain less of these substances.
The raw materials of shag are used in the pharmaceutical industry for the production of nicotinic acid (vitamin PP), the food industry for the production of citric acid and the textile industry.
Shag seeds contain 35-40% fatty oil, which is used in the manufacture of paints, varnishes and soaps.
Strong tobacco can serve as a raw material for the production of environmentally friendly insecticides. The soil and climatic conditions of many regions of Russia make it possible to significantly expand the sown areas of this crop.
Crop history
North America is considered the birthplace of shag.
Cultivation areas and yield
The cultivated area occupied by shag is much less than the cultivated area of tobacco. It is cultivated in India, Algeria, Tunisia, Poland.
Strong tobacco is cultivated in the Central Black Earth zone of Russia, in Mordovia, Chuvashia, Tatarstan and Western Siberia, as well as in Ukraine.
In the USSR, the sown area of shag was 10,000 hectares in the USSR.
Botanical description
Strong tobacco or makhorka (Nicotiana rustica L.) is an annual plant of the Solanaceae family. Not known in the wild. It is an interspecific hybrid from the natural cross-pollination of two wild species (Nicotiana undulata and Nicotiana paniculata).
Taproot, highly developed.
The stem is erect, ribbed, with a loose core. Plant height reaches 1.2-1.5 m.
The leaves are petiolate, fleshy, heart-shaped or ovate with a wrinkled surface, dark green, light green or yellow-green. The number of leaves per stem is a varietal characteristic and is usually 12-20.
In the axils of the leaves, lateral shoots are formed – stepchildren.
The stems and leaves are covered with short capitate hairs with a strong specific smell.
Inflorescence – panicle. The flowers are bisexual, green or yellowish-green, quintuple type, with bracts. Plants are self-pollinating, but cross-pollination is also noted.
The fruit is a bivalve (two-celled) multi-seeded box. In one box 200-600 seeds are formed. Seeds are small, brown or cream. Weight of 1000 seeds 0.25-0.35 g.
Biological features
Strong tobacco is less demanding on heat than tobacco. Germination of shag seeds begins at a soil temperature of 7-8 °C. The optimum temperature for growth and development is 20-25 °C.
Shag is sensitive to low temperatures, plants are damaged at a temperature of -2 … -3 °C.
Strong tobacco is demanding on moisture. Optimum soil moisture is 55-70% HB. The transpiration coefficient is 450-500.
Strong tobacco is a long day plant. With the advancement of its crops to the north, it accelerates its development, which allows it to be grown even in the Arctic.
Loamy chernozems, gray forest, sandy and loamy sod-podzolic soils are considered optimal for shag.
Vegetation
There are two periods in tobacco culture:
- growing seedlings from seeds in greenhouses or soil ridges;
- growing tobacco from seedlings in the field.
The seedling formation period usually lasts 45-50 days, but depends on the variety and usually ends by the time 5-6 true leaves appear.
The period from planting seedlings in the field to the onset of technical ripeness of the leaves of the upper tier lasts 80-120 days. Rooting of seedlings after its transplantation in the field is 10-15 days, after which the phases of stemming, budding, flowering, seed formation and maturation begin.
The formation of leaves in tobacco occurs in tiers.
Technological properties of leaves are determined by varietal characteristics, layering, growing conditions.
Crop rotation
The best predecessors of strong tobacco in the crop rotation are winter cereals, corn, root crops, legumes, annual and perennial grasses, vegetables.
Bad predecessors are gourds, potatoes (all solanaceous), hemp, sunflower, as they have common diseases and pests with it.
Strong tobacco serves as a good forerunner for many field crops.
Strong tobacco allows repeated crops.
Strong tobacco crop rotation
Among the strong tobacco crop rotations are used:
- grass-rowed:
- 1-2 – perennial grasses, 3-4 – strong tobacco, 5 – leguminous, 6 – strong tobacco, 7 – annual grasses with overseeding of perennial grasses – 42.7% strong tobacco;
- 1 – clover , 2-3 – strong tobacco, 4 – corn for silage, 5 – strong tobacco, 6 – annual grasses with overseeding of perennial grasses – 50% strong tobacco;
- tilled:
- 1 – corn for silage, 2-3 – strong tobacco, 4 – grain legumes, 5 – strong tobacco – 60% strong tobacco;
- 1 – annual herbs, 2 – strong tobacco, 3 – root crops, 4 – strong tobacco – 50% strong tobacco.
Fertilizer system
Strong tobacco consumes relatively few nutrients from the soil. For the formation of 100 kg of dry leaves and stems, it consumes 2.4 kg of nitrogen, 1 kg of phosphorus, 3.5 kg of potassium.
Strong tobacco responds well to the application of organic and mineral fertilizers. The application rate of manure depends on the fertility of the soil and is usually 40-60 t/ha. When combined with mineral fertilizers, the rate of manure is reduced.
The recommended application rates of mineral fertilizers to obtain a yield of dry leaves and stems of 3.0 t/ha on various soils are:
- on sod-podzolic – 120 kg/ha of nitrogen 120, 60 kg/ha of phosphorus, 90 kg/ha of potassium;
- on leached chernozems – 90 kg/ha of nitrogen, 60 kg/ha of phosphorus, 60 kg/ha of potassium;
- on peatlands – 20 kg/ha of nitrogen, 90 kg/ha of phosphorus, 120 kg/ha of potassium.
Manure and 2/3 of the entire norm of phosphorus and potash fertilizers are applied in autumn under deep plowing. In the spring, for cultivation, when sowing or planting seedlings and for top dressing, all nitrogen fertilizers and the rest of phosphorus and potash are applied.
Before sowing shag, a mixture is prepared in the field, consisting of superphosphate, at the rate of 20-30 kg of phosphorus, and 5-10 times the amount of humus. Seeds are poured into the mixture and mixed well, after which they are sown.
When planting seedlings, superphosphate (20 kg of phosphorus) and nitrogen fertilizers (15-20 kg of nitrogen) are applied simultaneously with irrigation water. The remaining amount of mineral fertilizers is used as top dressing.
Tillage system
Autumn tillage for strong tobacco includes:
- two peelings (after grain crops) with disc tools to a depth of 6-8 cm and 10-12 cm;
- early deep plowing by 25-30 cm (Vavilov; according to other recommendations 20-22 cm, Kolomeichenko).
In the spring, plowing is harrowed and 1-2 cultivations are carried out, followed by harrowing and leveling the soil surface.
Growing methods
Strong tobacco can be grown in two ways: seedlings (seedlings) and sowing seeds in the field (seeding).
The seedling method is important for the northern regions of cultivation. This method is associated with an increase in the cost of growing seedlings and planting them. However, low-lying areas flooded with hollow water and insufficiently structured soils can be occupied under it.
Elevated areas with light structural soils are best suited for seedlings.
Growing seedlings (saplings)
Strong tobacco seedlings are grown in greenhouses or on soil ridges.
The seeding rate in greenhouses is 1.5-2 g/m2, on warm beds – 2-2.5 g/m2, on cold beds – 2.5-3 g/m2.
Before sowing, the seeds are subjected to dressing in a weak solution of formalin and germinated at a temperature of 25-28 °C for 3-4 days. Before sowing, the seeds are mixed with clean sand in a ratio of 1:40.
For planting 1 hectare of shag, depending on the varietal characteristics, there are 30-45 m2 of greenhouses or 45-60 m2 of warm ridges.
Seedling care
Seedling care involves maintaining the optimum temperature (18-20 °C), thinning plants, 2-3 feedings, watering and hardening.
Seedlings ready for planting should have 5-6 true leaves and a height of 8-12 cm. Growing seedlings in greenhouses usually takes 30-35 days, in ridges – 40-45 days.
Transplanting
Planting seedlings of strong tobacco is recommended to be carried out in the early stages, after spring frosts, when the topsoil warms up to 10 °C. For the south of Ukraine, landing begins in late April – early May, in the Central Black Earth zone of Russia – in the second decade of May, in the north of the Non-Chernozem zone and in Siberia – in the third decade of May – early June.
Planting of seedlings is carried out manually or with the help of transplanters with a row spacing of 50-60 cm and a distance between plants of 20-30 cm.
For large-leaved varieties of shag, the plant density is recommended to be 60-70 thousand/ha, medium-leaved – 70-80 thousand/ha, small-leaved – 80-90 thousand/ha.
A square-nest method of placing plants according to the 50 × 50 cm scheme can be used, while two plants are planted in a nest.
Sowing (seedling)
They start sowing strong tobacco at an early date, simultaneously with the sowing of early grain crops.
For sowing, a mixture of germinated and dry seeds is used in equal amounts. Germinated seeds germinate 6-7 days after sowing, dry seeds – after 15-18 days. This approach allows you to get good seedlings if early shoots from germinated seeds have suffered from frost.
The method of sowing shag is wide-row with row spacing of 50-60 cm. For sowing, special or grain seeders with depth limiters can be used. The seeding rate is 2-3 kg/ha. Seeding depth no more than 1 cm.
Landing care
Before the emergence of seedlings during the formation of the soil crust, its destruction is carried out with the help of rotary hoes.
The first loosening of row spacing is done at the beginning of emergence to a depth of 5-6 cm. The second loosening is carried out 8-10 days after the first to a depth of 6-8 cm.
Bouquet of crops begins in the phase of two true leaves. With a wide-row sowing method with row spacing of 60 cm, the width of the cutout is 20 cm, and the length of the bouquet is 10 cm, the distance between the centers of the bouquets should be 30 cm. After 2-3 days, the bouquets are thinned, leaving 3-5 well-developed plants in them.
The final breakthrough is done 10-12 days after bouquet, when the plants have 5-6 leaves. With a wide-row sowing method, one plant is left in each bouquet, with a square-nested method – two of the best. Simultaneously with thinning, the first top dressing is carried out.
The recommended planting density of shag seedlings is the same as seedlings: 60-70 thousand plants per ha for large-leaved varieties, 80-90 thousand/ha for small-leaved varieties.
After thinning, 2-3 loosening of row spacings and top dressing are performed.
Before the first or second inter-row treatment, the seedlings and seedlings are cleaned, that is, the removal of 2-3 lower leaves.
During budding, topping is done, that is, the removal of inflorescences, and when lateral shoots grow by 5-7 cm, pinching.
Harvesting and drying
Harvesting of shag is carried out in one step with whole plants at the onset of technical ripeness, which is characterized by brittle leaves and their sagging. At the same time, mature leaves emit a strong peculiar smell. Delay in harvesting shag can lead to damage to plants by autumn frosts.
To speed up the drying of ripe shag, its stems are cut from top to bottom (plastered) 3-4 days before harvesting, leaving the lower part of the stem 5-6 cm long intact so that the plants do not die. The layering method allows to reduce drying by 10-12 days and reduce the loss of dry matter.
The shag is harvested by hand in dry, sunny weather. For this, the plants are cut down at the root, leaving not even small stumps. Cut down plants are left in the field for drying. Drying is completed when the leaves become soft and will not break when bent.
From the field, shag is transported to drying rooms, where it is subjected to languishing at a temperature of 30-40 ºС for 20-24 hours. The width of the stack is made equal to the length of two plants, the height is 50-70 cm. After languishing, the shag is dried for 25-30 days in well-ventilated rooms. Drying is considered complete when a moisture content of 35% is reached.
Sources
Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Tobacco
Tobacco (Nicotiana tabacum) is an alkaloid crop, also considered one of the most labor-intensive industrial crops.
Source: commons.wikimedia.org©Magnus Manske (CC BY-SA 3.0)
Economic importance
Tobacco is grown for its leaves, which are used as a raw material in the manufacture of cigarettes, cigars and pipe tobacco.
Tobacco leaves contain:
- nicotine 1-3%;
- essential oils – about 1%;
- resins – 4-7%;
- proteins – 7-10%;
- carbohydrates – 4-13%;
- ash – 13-15%.
The smell and aromaticity of tobacco are due to resins and essential oils.
Nicotine is synthesized by the root system of tobacco plants. This was proven by Academician A.A. Shmuk in 1941 together with employees. If tobacco is grafted onto a tomato , then nicotine is practically not found in tobacco leaves, and, conversely, up to 3-4% of nicotine accumulates in tomato leaves grafted onto tobacco.
Tobacco also serves as a raw material in the pharmaceutical industry.
Crop history
Tobacco is native to America. The Indians of South and Central America used tobacco leaves for smoking long before Europeans discovered the continent.
Cultivation areas and yield
Tobacco is currently grown in many countries around the world. The sown area of tobacco is more than 4 million hectares. More than half of the world’s production is in China, the United States, India and Brazil.
In the USSR, over 170 thousand hectares were occupied under tobacco crops. The main regions of cultivation are Moldova, the south and south-west of Ukraine, the countries of Central Asia and the Caucasus, in Russia – the North Caucasus. The average yield of tobacco is 1.5-2.0 t/ha. The maximum yields that could be obtained were 3.0-3.5 t/ha. For example, in the collective farm named after Krupskaya, Urgut district, Samarkand region of Uzbekistan, on an area of 1027 hectares, the yield reached 3.6 t per hectare with an output of 87% of the highest grades.
Botanical description
Tobacco (Nicotiana tabacum L.), or cultivated tobacco, is an annual plant belonging to the Solanaceae family. The genus includes about 70 species.
The root is taproot, penetrates the soil to a depth of 1.5-2 m. The stem is erect, pubescent. Plants reach 100-180 cm in height.
The leaves are large, petiolate or sessile, entire, oval, ovate or elliptical, pointed, with a smooth or wrinkled surface. The number of leaves on one plant reaches 25-50 pieces. Their number and size depend on the variety type and growing conditions. The leaves and stem are covered with short sticky hairs.
Inflorescence paniculate, corymbose. Flowers bisexual, pedicel, pentate, with bracts. The calyx is bell-shaped. The corolla is longer than the calyx, covered with hairs on the outside. The corolla tube is white, the limb is pink or red. The ovary is superior, often bilocular. The stigma is bilobed. Stamens five.
Tobacco is a self-pollinator, but cross-pollination is possible.
The fruit is a two-celled, multi-seeded, oval capsule, 1.5-2.0 cm long, brown, cracking when ripe. In one box, up to 5000 thousand seeds can be formed.
Seeds are oval, dark brown, very small. Weight of 1000 seeds (0.05) 0.06-0.08 (0.12) g.
In tobacco growing, two groups of tobacco are distinguished – cigarette and cigar. Cigarette tobacco is divided into Oriental and American. In the USSR, oriental cigarette tobacco was most widely used, the varieties of which, according to smoking qualities, are divided into aromatic (flavoring, added to tobacco raw materials in small quantities) and skeletal, which form the basis of smoking products.
Biological features
Temperature requirements
Tobacco seeds begin to germinate at a temperature of 10-12 °C. The optimum temperature is 25-30 °C. At temperatures above 35 °C, tobacco growth stops.
Frosts -2 … -3 °С are detrimental to young plants. However, in autumn, tobacco tolerates short-term low temperatures well.
Moisture requirements
The optimum soil moisture for tobacco is 65-70% from the lowest soil moisture capacity.
The greatest need for water falls on planting and rooting seedlings, as well as during the formation of leaves and intensive plant growth. The lack of moisture at this time leads to a decrease in leaf size and premature ripening, which causes a decrease in yield and quality of tobacco.
Excess moisture, especially on heavy clay soils, leads to wetting of plants.
Transpiration coefficient 500-600.
Soil requirements
Light textured soils with a low humus content are considered optimal for tobacco. An excess of organic matter in the soil leads to a deterioration in the smoking qualities of tobacco.
Tabakh is a chlorophobic culture. Sodium and calcium chloride compounds in the soil reduce its combustibility.
Heavy clay, saline and waterlogged soils are unsuitable for cultivation.
Light requirements
Tobacco belongs to light-loving plants.
The lack of illumination leads to a delay in the development of plants and a decrease in the quality of raw materials.
Vegetation
There are two periods in tobacco culture:
- growing seedlings from seeds in greenhouses or soil ridges;
- growing tobacco from seedlings in the field.
The seedling formation period usually lasts 45-50 days, but depends on the variety and usually ends by the time 5-6 true leaves appear.
The period from planting seedlings in the field to the onset of technical ripeness of the leaves of the upper tier lasts 80-120 days. Rooting of seedlings after its transplantation in the field is 10-15 days, after which the phases of stemming, budding, flowering, seed formation and maturation begin.
The formation of leaves in tobacco occurs in tiers.
Technological properties of leaves are determined by varietal characteristics, layering, growing conditions.
Crop rotation
The best forerunners of tobacco in a crop rotation are considered to be winter crops, sugar beets, corn, annual legumes and grasses. On less fertile soils, tobacco is recommended to be placed after leguminous crops and along the reservoir turnover.
With a high saturation of the crop rotation with tobacco, it is allowed to re-plant it in a year, after which it is returned to this field only after 3-4 years. However, the scientifically substantiated inclusion of tobacco in the crop rotation allows increasing its yield by 1.5-2 times compared to permanent and repeated crops.
According to the All-Russian Research Institute of Tobacco and Shag, tobacco is recommended to be placed on light sandy, coarsely skeletal and low-humus podzolized piedmont soils along a layer of perennial grasses; on rich fertile soils – according to the turnover of the layer, in some cases in the third year after perennial grasses.
Tobacco crop rotation
Plantings of tobacco are usually placed near water sources and drying facilities. For this reason, this crop is cultivated in special tobacco crop rotations with a narrow set of crops.
Tobacco crop rotations are tilled, grass-rowed, fruit-shifting. They are built on the placement of tobacco according to the best predecessors for it – winter wheat, perennial grasses, sugar beets, corn, annual legumes and cereal grasses.
Undesirable predecessors are hemp, sunflower, gourds, nightshade crops, as they have pests and diseases in common with tobacco.
In the foothill regions of the Krasnodar Territory, the following tobacco crop rotation is used: 1-2 – alfalfa of the 1st-2nd year of use, 3 – tobacco, 4 – corn, 5 – tobacco, 6 – annual grasses, 7 – tobacco, 8 – spring barley with oversowing perennial herbs. The share of tobacco is 37.5% of the total area.
On poor podzolized soils of the Krasnodar Territory, tobacco is cultivated according to the layer of perennial grasses, as well as in the third year after them in crop rotation: 1-2 – perennial grasses of the 1-2nd year of use, 3 – tobacco, 4 – corn or Sudanese grass, 5 – tobacco, 6 – spring barley with overseeding of perennial grasses. The share of tobacco is 33% of the area.
In a number of farms in the Krasnodar Territory, crop rotation is used: 1-2 – perennial grasses of the 1st-2nd year of use, 3 – winter wheat, 4 – tobacco, 5 – winter wheat, 6 – tobacco, 7 – Sudanese grass, 8 – tobacco.
In the foothill regions of the Kuban, the following 8-field grain-grass row (fruit shift) crop rotation is used: 1-2 – perennial grasses, 3 – winter wheat, 4-5 – tobacco, 6 – winter wheat + intermediate crop, 7 – tobacco, 8 – corn.
In the humid zone of the subtropics of the Krasnodar Territory, the following tobacco crop rotation was introduced: 1 – two-cut clover, 2 – tobacco + intermediate crop, 3 – corn + intermediate crop, 4 – tobacco, 5 – cereals with clover oversowing.
Fertilizer system
Tobacco places high demands on nutrient availability. On average, for the formation of 100 kg of leaves, it absorbs from the soil 6 kg of nitrogen, 1.7 kg of phosphorus, 4.6 kg of potassium and 6.7 kg of calcium. Therefore, this crop responds well to the application of organic and mineral fertilizers.
In turn, nitrogen fertilizers should be used in moderation, since excess nitrogen in the soil degrades the quality of tobacco raw materials. The combined application of nitrogen and phosphorus-potassium fertilizers weakens the negative effect of excess nitrogen.
Since tobacco is a chlorophobic crop, it is not recommended to use chlorine-containing fertilizers.
To obtain 15-20 kg/ha of tobacco leaf yield, it is recommended to apply 10-15 t/ha of manure, 30-60 kg/ha of nitrogen, 80-120 kg/ha of phosphorus, 70-100 kg/ha of potassium (Vavilov; according to others data, from N15-20P50-60K70-75 to N45-60P90-100K120-150, Kolomeichenko). Manure and 2/3 of the entire norm of phosphorus and potash fertilizers are applied in the fall for deep plowing, nitrogen and the rest of the phosphorus and potash fertilizers are applied in the spring during cultivation and for top dressing. When cultivating tobacco under irrigation or excessive moisture, mineral fertilizers are applied in the spring under plowing.
Top dressing is carried out at the beginning of intensive growth of tobacco, that is, 10-12 days after planting seedlings. With weak growth, a second top dressing is carried out 8-10 days after the first.
The lack of boron in the soil can cause the tops of tobacco plants to dry out.
Tobacco responds positively to zinc and lithium fertilizers. For foliar top dressing, a solution containing up to 0.1% lithium is used.
Tillage system
Autumn tillage provides for:
- double stubble peeling to a depth of 5-7 cm and 10-13 cm;
- autumn tillage to a depth of 25-30 cm (Vavilov; according to other sources, 20-22 cm, Kolomeychenko), which should be carried out in a timely manner.
Spring tillage includes:
- fallow harrowing;
- 2-3 cultivations with simultaneous harrowing.
The number of cultivations depends on the weediness of the fields and the timing of planting seedlings.
Growing seedlings
Tobacco is grown only in seedlings. Seedlings are grown in heated and solar greenhouses (nurseries), in film greenhouses or on soil ridges.
Nurseries should be placed on level ground with a slight slope to the south or southwest. They should be well lit and located away from tobacco fields, dryers and tobacco storage facilities in order to prevent infection of seedlings with grouse, mosaic and other diseases.
Nurseries for tobacco are prepared in the same way as for vegetable crops.
Sowing
The timing of sowing tobacco seeds in nurseries is determined by the timing of planting seedlings in the field. Depending on the type of nursery and weather conditions, it takes 35-65 days to get ready seedlings. For example, in the North Caucasus, seedlings in heated greenhouses are obtained on the 45th day, in sunny – on the 55th, in soil beds – on the 60th day after sowing.
The seeding rate for greenhouses is 0.6 g/m2, warm ridges – 0.8 g/m2, cold ridges – 1 g/m2.
Seedling care
Tobacco seedling care includes:
- irrigation;
- ventilation;
- top dressing;
- weeding;
- pest and disease control.
Watering the seedlings is done in small portions of water, but often, preventing the surface of the nutrient mixture from drying out.
The optimum temperature from sowing to germination is 22-28 °C, after germination – 18-25 °C. In greenhouses with technical heating, the temperature is regulated by heating, in greenhouses of another type – by ventilation and covering them with insulation mats.
3-4 times the seedlings are fertilized with mineral and organic fertilizers. The rate of application of mineral fertilizers in top dressing in the form of a solution: nitrogen 2 g/m2, phosphorus 2 g/m2, potassium 5 g/m2. The consumption of the solution is 200 l per 100 m2.
For fertilizing with organic fertilizers, fermented infusion of chicken manure, diluted 1:20 or 1:30, is usually used.
Weed control on seedling crops is carried out as they appear.
Thickened seedlings are thinned out.
Before weeding and thinning, if the nurseries are dry, watering is carried out.
By the time of planting, the seedlings should have a well-developed root system, a flexible, dense stem with 5-6 true leaves.
Seedlings are hardened before sampling. To do this, for 8-10 days it is watered after 1-2 days, stopping it 2-3 days before transplantation.
The output of seedlings is 2500 pcs/m2 on greenhouses with a warming layer, 2000 pcs/m 2 on solar greenhouses, 1500 pcs/m2 on soil ridges. There are 40-60 m 2 of nurseries per hectare of plantings, depending on the variety.
NPO “Tabak” and the Moldavian Research Institute of Tobacco developed a technology for growing seedlings on a nutrient mixture that has not been replaced for 4-5 years. The technology provides for the annual disinfection of greenhouse or greenhouse soil.
Transplanting
Planting seedlings in the field is started when the temperature of the topsoil reaches 10-12 °C and the danger of frost has passed. For most tobacco-growing areas, these conditions fall on the third decade of April. Planting seedlings should be completed before the third decade of May.
Early planting dates are advantageous, especially in the Crimea, where spring is often dry.
The density of standing tobacco plants depends on the area of cultivation and varietal characteristics:
- small-leaved varieties are planted according to the scheme 50 × 12 cm at a plant density of 150-200 thousand pieces/ha;
- medium-leaved – 60 × 20-24 cm with a density of 80-90 thousand pieces/ha;
- large-leaved – 70 × 30 and 90 × 20 cm with a density of 45-55 thousand pieces/ha.
Tobacco planting is carried out by transplanters. For row planting, the МПР-4 transplanter can be used.
Landing care
An important technique for caring for tobacco plantings is considered to be inter-row tillage, which is usually 3-4 with an interval of 8-12 days.
The first treatment is carried out to a depth of 6-8 cm, the subsequent – 10-12 cm. If the soil moisture is insufficient, the treatment is done to a depth of 6-8 cm.
When growing tobacco under irrigation conditions, plantations are watered 2-6 times. Irrigation rate 500-800 m3/ha.
Special methods of planting care are cleaning, topping and pinching tobacco.
Erasure – removal of the lower seedling leaves, followed by their destruction. This technique contributes to a better development of the leaves of the following tiers.
Topping – removal of inflorescences. It is carried out from the beginning of flowering 3-4 times.
Pasynkovanie – removal of side shoots. Carried out simultaneously with topping.
Topping and stepping help to increase the yield, due to the fact that plastic substances are not spent on the further development of inflorescences and side shoots, but are used by the leaves.
Tobacco is considered a medium competitive crop. Parasitic weeds (broomrape (Orobanche) and dodder (Cuscuta)) can appear in tobacco plantations. In the fight against parasitic weeds, crop rotation is of great importance, which should include crops resistant to these weeds: barley, wheat, rice, oats, millet or perennial cereal grasses.
The main pests of tobacco include: slugs, bear, tobacco thrips, wireworm, meadow moth, black weevil. Main diseases: black root rot, bacterial grouse, powdery mildew, mosaic, ring spot, etc.
Harvest
Tobacco leaves ripen unevenly. The oldest lower leaves ripen first, then the middle and last the upper leaves. Most varieties have five tiers of ripening.
Tobacco leaves are harvested by hand. For this, 5-10 breaks are made within 1.5-2 months. The number of breaks, as a rule, coincides with the number of maturation tiers. For one break, 3-7 leaves are removed from one plant.
The harvested leaves are stacked in packs and immediately sent to drying sheds, where they are sorted, strung on cords 5-6 m long and dried.
Drying tobacco
Tobacco drying is carried out in two phases: languor and fixation (drying itself).
Languishing is carried out in drying sheds on special frames – wagons on which cords with strung leaves are hung. The optimal languishing temperature is 25-30 °C, while breathing and evaporation of moisture by plants continues. When languishing in the tissues of the leaf, the breakdown of proteins occurs, the conversion of starch into sugar and the destruction of chlorophyll. The content of nicotine in the leaves decreases, but the amount of aromatic substances increases. Moisture loss during languishing is 6-7%, dry matter – 10-16%. As a result of languishing, the leaves turn yellow, their quality increases. The duration of languor is usually 3-4 days.
After languishing, fixation is carried out, that is, the final drying of tobacco in the sun for 15-20 days or in special fire dryers at a temperature of 40-42 °C at the beginning of drying and 48-50 °C at the end.
For tobacco drying, СТГ-1.5 production lines can be used, which can reduce labor costs by 35-40% compared to pipe-fired drying. The production line СТГ-1.5 for drying tobacco, fixed on cords in vertical garlands, allows the use of a continuous technology of languishing, drying and moistening the leaves.
A relatively newer way of drying large-leaf tobacco – in bulk – is to place the leaves in cassettes equipped with metal needles. For this method, the СТМ-60, УСТП-10, 801-ТУ installations are used.
After drying, the leaves are sorted according to the established standard into five grades, tied into bales and handed over to procurement points. Humidity of commercial raw materials in bales (20-25 kg each) should not exceed 19%. From the procurement points, tobacco is sent to fermentation plants to improve quality and impart resistance to mold, from where it is already delivered to tobacco factories.
Sources
Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Medicinal and alkaloid plants
Medicinal and alkaloid plants include:
- geranium (Geranium);
- fenugreek (Trigonella);
- motherwort heart (Leonurus cardiaca);
- five-lobed motherwort (Leonurus quinquelobatus);
- golden root (Rhodiola rosea);
- yarrow (Achillea millefolium);
- Jacob’s-ladder (Polemonium caeruleum);
- coneflowers (Echinacea);
- clary sage (Salvia sclarea);
- common sage (Salvia officinalis);
- elecampane (Inula helenium);
- common nettle (Urtica dioica);
- common thyme (Thymus vulgaris);
- greater celandine (Chelidonium majus);
- belladonna (Atropa belladonna);
- fireweed (Epilobium);
- goat’s rue (Galega officinalis);
- greater burdock (Arctium lappa);
- great burnet (Sanguisorba officinalis);
- tobacco (Nicotiana tabacum);
- strong tobacco (Nicotiana rustica);
- peppermint (Mentha piperitя) ;
- Valerian officinalis (Valeriana officinalis);
- Tangut rhubarb (Rheum palmatum);
- chamomile (Matricaria chamomilla);
- marigold (Calendula);
- winter rye spores.
In Russia, medicinal plants are cultivated in specialized farms in the south, in the non-chernozem and forest-steppe zones, in some regions of Siberia and the Far East.
In total, more than 50 species of medicinal plants have been introduced into the culture.
- Medicinal and alkaloid plants (Русская версия)
Importance
One of the most sought-after herbal medicines is Valeriana officinalis L, which contains a large amount of essential oils, valerian and other organic acids, borneiol, alkaloids and other substances. Drugs from it have a regulatory effect on the nervous system, the heart muscle, contribute to the expansion of coronary vessels, have antispasmodic effect and normalize blood circulation.
The important among natural sources of medicinal raw materials is the hybrid catnip (Nepeta x faasenii B er gm. ex Steam.), which has the ability to accumulate essential oils and is a valuable spicy, aromatic and medicinal introducer, promising for introduction into industrial and horticultural culture. Cattleya is also valuable as a raw material for soft drinks and in perfumery.
Estragon (Artemisia dracunculust) accumulates essential oils (0.1 to 0.8%) that have insecticidal properties. In addition, leaves and stems contain tannins, vitamin C (up to 70 mg %), provitamin A, rutin and trace elements – copper, manganese and cobalt. Estragon is a valuable spicy and aromatic introduced species, promising for introduction into industrial and horticultural culture. The green mass of tarragon is used in cookery as a salad dressing as a spice, for salting and making marinades. Extracts for flavoring soft drinks are prepared from tarragon greens.
Common oregano (Origanum vulgare L.) is an essential oil and is characterized by a high content of essential oils (up to 2.17%), ursolic acid, C and B vitamins, phenolcarbonic acids, tannins and flavonoids. Oregano herb is part of a sedative gathering for the treatment of neuroses and normalization of blood pressure.
Melissa officianalis V. is a valuable medicinal plant that contains up to 0.33% essential oil with a pleasant lemon scent. The oil contains citral, myrcene, geraniol, cineol and aldehydes. The leaves contain tannins, various acids, vitamin C and carotene; seeds contain up to 20% of fatty oils. Melissa is used in medical practice as an antispasmodic, regulating the gastrointestinal tract. Recommended to relieve nervous tension, with migraines, insomnia and skin rashes.
The leaves and inflorescences of Salvia officinalis L. contain up to 2.65% essential oil, as well as tannins, alkaloids, vitamin C and carotene. The seeds contain 19-25% fatty oils. The above-ground parts of sage have anti-inflammatory, antibacterial, astringent, styptic, diuretic and sedative effect.
History
The ancestors of modern man used wild plants for not only nutrition, but also for treatment. After the advent of agriculture, people learned to grow some of them.
The first written evidence of the use of medicinal plants refers to the state of the Sumerians, which existed on the territory of modern Iraq in 6000 BC.
Treatment with the help of plants – phytotherapy – still exists today, despite the widespread use of artificially synthesized pharmaceuticals. Many medicinal plants are collected and harvested in natural phytocenoses (forests, swamps, meadows, steppes, mountains, etc.). However, since the second half of the XX century. more purposeful introduction and selection of the most valuable medicinal plants began.
In the State Register for 2006, several dozen varieties of medicinal plants were included. Thus, at the end of the 20th century, a new group of industrial crops appeared in crop production – medicinal and alkaloid plants.
A clear distinction between medicinal plants and other field crops cannot be called clear. So some essential oil crops (coriander, anise, peppermint, clary sage, etc.) can be included in a separate group of medicinal plants. Often, tobacco and shag are isolated separately.
Alkaloid plants (cocoa, tea, coffee, poppy, etc.) are widely used, which contain various alkaloids (ephedrine, caffeine, quinine, nicotine, etc.) and have a strong physiological effect on the nervous system of humans and animals. Due to the content of alkaloids in these plants, they are widely used in medicine and veterinary medicine.
Despite the fact that tobacco and shag smoking, due to the negative impact on human health, has become catastrophic in our country and throughout the world, the nicotine alkaloid (a strong poison!) Obtained from these plants is used to produce pharmaceuticals and insecticides.
It should be noted that some cereals, legumes, technical and fodder crops, in addition to their main purpose, can also be used as medicinal plants. So, in some textbooks, amaranth is classified as a rare fodder plant, but in the ancient American states (Aztecs and Incas), this culture was used as a medicinal and food crop. Also, leuzea safflower-like (maral root) and Jerusalem artichoke can be simultaneously attributed to fodder and medicinal plants.
Medicinal crop rotations
Medicinal cultures are subject to high requirements for product purity. Therefore, they are cultivated in environmentally friendly conditions. Growing technology eliminates their contamination with residual agrochemicals, therefore, great importance is attached to the use of organic fertilizers, agrotechnical and biological methods of protecting plants from diseases, pests and weeds, and primarily crop rotation.
In most cases, medicinal crops are introduced into regular field, special and sometimes fodder crop rotations. They are placed according to the best predecessors – bare and seeded fallows, layer and turnover of the layer of perennial grasses, legumes, after winter crops, following the best predecessors, row crops.
Perennial medicinal crops can be introduced into hatching fields, where they are cultivated continuously for several years.
Features of cultivation
The development of industrial technology of cultivation of catnip hybrid, catnip catnip, tarragon, valerian, oregano, melissa and sage was based on the development of basic agronomic practices on the basis of modern technical means to ensure maximum productivity of plants at minimum labor costs for their growth.
Requirements to the soil
The best soils for cultivation of aromatic and medicinal plants are loamy loamy soils with humus content not less than 2%, P2O5 compounds 18,0-22,0 and K2O – 20,0-26,0 mg/100 g, with a tilling depth of 20-25 cm and pH 6,0-7,0.
Soil preparation
In the early spring period, organic and mineral fertilizers are applied, the optimum doses of which are shown in the figure.
After fertilizer application, the soil is carried out chiseled with a cultivator to a depth of 30 cm. From the ridged profile formed by the cultivator and mud-former, narrow profile trapezoidal ridges with a width of 20 cm in the upper part, 40 – in the lower part, a height of 14-16 cm are formed. To avoid soil drying out, ridging and formation of ridges is made on the day of sowing or planting seedlings.
Fertilizers
Recommended fertilizer rates for aromatic and medicinal crops:
- Melissa officinalis: 1-2 year – N60P90K120, 3 year – N75P120K150;
- Sage medicinalis (Salvia officinalis): 1-3 years – N60P80K120;
- Catnip (Nepeta cataria): N90P120K150;
- Estragon (Artemisia dracunculus): N90P120K150;
- Valeriana medicinalis (Valeriana officinalis): 1 year – N90P90K120 + 50 t/ha of organic fertilizer, 2 year – N120P90K120;
- Hybrid catnip (Nepeta x faasenii): 1 year – N45P60K90 + 50 t/ha of organic fertilizer, 2-3 years – N120P150K180;
- Oregano common (Origanum vulgare): 1 year – N15P120K150, 2 and 3 years – N60P90K120.
Sowing
Production of aromatic and medicinal plants is recommended to be maximally oriented to the seedling culture, because it significantly reduces the use of seeds and expenses to fight with weeds, and also increases the productivity of plants in the first year of their growth. Estragon, sage, catnip and hybrid seedlings are planted under the scheme 70 x 30 cm, valerian, oregano, melissa – 70 x 15-20 cm, the number of plants is respectively 47.6 and 71.4 thousand pcs / ha. Seeding is carried out in a double-line technique with a distance between the lines of 8 cm and a row spacing of 70 cm. Seeding rate is determined depending on the germination of seeds. With 40% germination of valerian seeds, the seeding rate is 10 kg/ha, with 50% and 60% germination – respectively 8.8 and 7.3 kg/ha. Seeding depth – not more than 1-1.5 cm on loamy soils and 2 cm – on soils with lighter texture.
The timing of sowing valerian seeds is determined by the timing of planting seedlings. If the seedlings are planned for planting in late September, sowing is carried out at the end of the 1st decade of July. When planning to plant seedlings in April, sow in the II-III decade of July, so that the plants have time to develop and mature by winter. It is desirable to sow fresh seeds, as they quickly lose their germination during storage.
Estragon and catnip hybrid propagate only vegetatively (green cuttings, bush division). Cuttings are planted in plastic cassettes with the volume of cells 65 cm3, filled with peat (pH 6-6,5) with 0.15 kg/m2 – urea, 0.2 – potassium sulfate and 0.25 kg/m2 – double superphosphate. Cassettes with cuttings kept at a temperature of 18-20 ° C and relative humidity of 80-90%. During the winter period, cuttings should be taken from mother plants transplanted into the climatic chamber in mid-October, in the spring and autumn period – from field plants.
Planting care
As weeds appear, inter-row cultivation is carried out with a cultivator with a set of working tools – lancet tine, side razors, rotary harrow and hiller. Crops are weeded manually, which eliminates the use of herbicides and makes it possible to obtain high-quality raw materials.
Due to the fact that valerian gives flower-bearing shoots, it is necessary to ensure their timely removal (“rejuvenation”, or topping). This usually coincides with the 1st weeding. “Rejuvenation” of crops is also carried out manually. During the growing season, there are 2-3 weeding operations, “rejuvenating” as needed, and 3 inter-row treatments. During the 2nd treatment, plants in the rows are fed with ammonium nitrate (50-70 kg/ha).
Harvesting
Grasses may be harvested by rotary mower (Л-501, Л-502) at a cutting height of 15-20 cm from the soil surface (catnip, tarragon), 8-10 cm (catnip hybrid, oregano, melissa, sage). The raw mass is placed in windrows, loaded on a trailer and taken for drying. Drying can be carried out on floor dryers with active ventilation. Avoid direct sunlight.
Roots of valerian is usually harvested in the fall 2-3 weeks before the soil freezes, as intensive root growth and accumulation of biologically active compounds continues until mid-September. Roots harvested in the fall have better marketable qualities than roots harvested in the spring. Harvesting can be carried out with potato diggers with subsequent clearing of soil and manual pruning of roots at the base of the root neck. Valerian, grown by seedling method on a high agrophon, has powerful thickened rhizomes, so for a more complete removal of soil during washing large rhizomes are cut along the longitudinal axis into 2-4 parts. To avoid loss of active substances they are quickly washed, dried 1-2 days under awning, then dried in dryers at a temperature not exceeding 35-40 ° C. Moisture of the dried roots should not exceed 18%.
Multifaceted use technology
Taking into account the peculiarities of the implementation of many medicinal plants, the Kabardino-Balkarian Agricultural Academy (Fisun M.N.) proposed a technology for the multilateral use of plants that simultaneously have medicinal, fodder, decorative and other properties.
Under production conditions, a comprehensive experiment was carried out, in which single-species tape crops of goat’s rue, high elecampane, woolly comfrey and dioica nettle are used depending on the market situation. If it is possible to sell medicinal raw materials, cleaning is carried out along the tapes. If there is no opportunity to sell medicinal raw materials, the plants are used to harvest high-quality silage or haylage, for which the green mass is mowing across the tapes. Such permanent multi-purpose plantations showed high and stable productivity: 2.5-4 t/ha of medicinal raw materials or 45-60 t/ha of green mass.
Sources
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Modern technologies in vegetable production / Dr. A.A. Autko [etc.]; edited by A.A. Autko. – National Academy of Sciences of Belarus, Institute of Vegetable Growing. – Minsk : Belarus. nauvuka, 2012. – 490 p., [16] l. ill.
Kenaf
Kenaf (Hibiscus cannabinus) is a valuable fiber crop.
Source: commons.wikimedia.org©Tubifex (CC BY-SA 3.0)
- Fiber crop
- Cotton
- Fiber flax
- Kenaf (Русская версия)
Economic importance
Kenaf stems contain up to 24% fiber, which is strong, soft and hygroscopic. Tarpaulin, sacking, container, carpet and furniture fabrics, ropes, ropes and other products are made from fiber.
The kenaf fire is used for the production of building boards and paper. The seeds contain 18-20% oil (fat), which is used in the leather, soap and paint industries. The cake goes to feed livestock.
Crop history
The homeland of kenaf is considered to be South America, where it is distributed in the wild.
Cultivation areas and yield
Kenaf is grown in India, China, Indonesia, Burma, Sudan, Brazil.
On the territory of the former USSR, kenaf is cultivated on irrigated lands in Uzbekistan. The area under crops in the 1980s was about 15 thousand hectares (statistics for the USSR).
On green and seed crops, the yield of kenaf stalks can reach 18 t/ra or more. The largest yields of 20-25 t/ha were obtained annually on the Politotdel collective farm of the Communist region, the Akhunbaev collective farm of the Srednechirchik region, the Lenin collective farm of the Galabinsky region of the Tashkent region, etc.
Botanical description
Kenaf (Hibiscus cannabinus L.) is an annual herbaceous plant of the Malvaceae family .
The root is taproot, well developed, penetrating to a depth of more than 2 m.
The stem is round or slightly ribbed, 2 to 5 m high, branched, with anthocyanin coloration. At the base, the thickness of the stem is 1.5-2.0 cm.
The leaves are alternate: the lower ones are simple, the middle ones are lobed, the upper ones are lanceolate with serrated edges.
The flowers are large, up to 7 cm in diameter, five-petalled, yellow, cream, light lilac, pink in color with a dark cherry or pale reddish spot inside the corolla. Plants begin to bloom from the lower flowers. Each flower blooms for one day. Self-pollination prevails, with underdeveloped anthers, cross-pollination can be observed.
The fruit is a five-celled, ovoid-pointed capsule, about 2.5 cm long, 1-2 cm wide, covered with fine bristles. On one plant, 20-30 boxes are formed.
Seeds triangular, dark gray. One box contains 15-20 seeds. Weight of 1000 seeds 20-28 g.
Biological features
Temperature requirements
Kenaf is a thermophilic plant.
Seeds begin to germinate at a temperature of 10-12 °C. The optimum temperature for the appearance of uniform seedlings is 20-22 °C.
Frosts -1.0 … -1.5 °C lead to the death of seedlings and adult plants.
The optimal temperature for the growth and development of kenaf is 23-25 °C. By the end of the growing season, heat requirements are noticeably reduced.
Moisture requirements
For kenaf, the optimum soil moisture is 80% from the lowest soil moisture capacity. Therefore, kenaf can be cultivated either in irrigated conditions or in regions rich in rainfall.
The greatest need of plants for water falls on the period of rapid growth, that is, when a three-blade leaf appears.
Soil requirements
Typically, kenaf is sown on alluvial soils of river valleys, gray soils, meadow and meadow-marsh soils.
Salt and waterlogged soils are not suitable for cultivation.
Light requirements
Kenaf is a photophilous plant of a short day.
The lack of lighting, which can be observed on heavily thickened crops, leads to short stature and weakening of plants.
Vegetation
The vegetation period of kenaf is 120-160 days.
Crop rotation
In crop rotation, the predecessors of kenaf can be winter cereals, tilled crops, legumes and alfalfa.
Fertilizer system
Kenaf is a rather demanding culture in terms of nutrition. With a stem yield of 10 t/ha, kenaf removes 120-150 kg of nitrogen from the soil, 60-80 kg of phosphorus and 120-160 kg of potassium.
At the beginning of the growing season, the greatest need is noted for phosphorus and potassium. Nitrogen consumption increases significantly during the budding and flowering phases.
Kenaf is responsive to fertilization. A particularly good result is obtained from the joint application of manure (15-20 t/ha) and mineral fertilizers.
The approximate recommended application rate of mineral fertilizers to obtain 18-20 t / ha of stems is: nitrogen – 220-250 kg, phosphorus – 150-170 kg and potassium K – 90-100 kg/ha. When placing kenaf after alfalfa, the fertilizer rates in the first year are somewhat reduced.
Manure and half of the total norm of phosphorus and potash fertilizers are applied for autumn tillage, 25-30 kg/ha of nitrogen and phosphorus – at sowing, the rest of the fertilizer – for top dressing. Top dressing of crops of kenaf is carried out in the phase of 8-10 leaves and in the phase of the beginning of budding.
Tillage system
Tillage for kenaf includes:
- peeling;
- autumn plowing with plows with skimmers to a depth of 28-30 cm in September;
- early spring plowing;
- 1-2 cultivations with simultaneous harrowing.
Before sowing, the field is planned and harrowed.
Sowing
Seed preparation
Before sowing, conditioned seeds are subjected to air-heat treatment in open areas. Seeds are treated with 80% TMTD at the rate of 200 g/100 kg of seeds.
Sowing dates
Sowing of kenaf is started when the soil warms up to 12-15 °C.
For Uzbekistan, the optimal sowing time for greens is April 10-20, when grown for seeds – April 1-10.
Seeding methods
The most progressive method of sowing when growing greens is a two-row belt with a width between the ribbons of 70 cm and a distance between the lines of 20 cm. The seed sowing rate by this method is 25-30 kg/ha.
With the seed crop of kenaf, a wide-row sowing method with row spacing of 60 cm is usually used. The sowing rate in this case is 8-10 kg/ha.
Seeding depth
Sowing depth on light soils is 5-6 cm, on heavy soils – 3-4 cm.
Crop care
Kenaf plants at the beginning of the growing season develop slowly, so the greatest care is required for crops during this period. The destruction of the soil crust at this time is carried out with the help of light harrows.
During the growing season, the number of inter-row treatments reaches 5-6. They are carried out immediately after watering, as soon as it becomes possible due to the state of soil moisture. Usually, inter-row cultivation continues until the rows close.
During the growing season, 5-6 waterings are carried out on green crops: the first watering is carried out at a plant height of 12-15 cm, the next – after 15-20 days. The irrigation rate is 1000-1200 m3/ha.
On seed crops, after the first cultivation, thinning is done, after which the plant density should be 150-180 thousand plants per 1 ha. Three waterings are usually carried out: the first – in the phase of 18-20 leaves, the second – in the budding phase, the third – in the flowering phase. Irrigation rate – 3500-4000 m3/ha.
Harvest
The harvesting of kenaf for greenery is started at the onset of technical ripeness, that is, when at least 50% of the plants bloom. To obtain bast, freshly cut stems are processed using a ЛО-1А bast separator. The resulting green bast is dried, for which it is spread over the stubble in an even layer. After drying, the bast is collected in bales weighing 10-12 kg. Before delivery to the procurement points, the bast is sorted.
Kenaf harvesting can be carried out using kenaf harvesters, for example, КУ-0.2, which cuts the stems, separates the undergrowth and weeds, processes the stems into bast and lays them on the ground to dry.
Harvesters ЖК-2.1 are used for harvesting kenaf for seeds. Harvesting is started when 3-4 lower bolls are browned in 75% of plants. In the conditions of the Tashkent region, which is the only producer of kenaf seeds for all regions of Uzbekistan, harvesting is usually carried out on September 5-16.
Cut stems are dried, for which they are left on the field for 3-4 days. Then the stems are tied into sheaves and set in small musts to dry. Dried sheaves are subjected to threshing, for which mobile threshers МКФ-6 are used. Seeds are sorted, and the remaining stems are tied into sheaves and sent for delivery to bast plants.
Sources
Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).
Fiber flax
Fiber flax is an agricultural fiber crop.
Source: commons.wikimedia.org©H. Zell (CC BY-SA 3.0)
- Fiber crop
- Cotton
- Fiber flax (Русская версия)
Economic importance
The flax stem contains 20-30% of bast, in highly productive varieties and more. Linen fiber is characterized by high technological properties: strength, flexibility, thinness, etc. It is 2 times stronger than cotton fiber, three times woolen and second only to silk.
Linen fiber is used for the production of household, technical, container and packaging fabrics. From 1 kg of fiber, 10 m2 of batiste or 2.4 m 2 of linen, 1.6 m2 of technical fabrics or 1 m2 of tarpaulin are produced. Linen fabrics are wear-resistant and resist decay. They are in demand all over the world.
In the production of fabrics, flax fiber is considered one of the best components when used together with chemical fibers.
Flax seeds contain 35-42% by weight of seeds of a well-drying oil, which is used in the production of paints, varnishes, drying oils, in soap making, paper, electrical and other industries, as well as in medicine and perfumery. A small part of linseed oil is used for food purposes.
Flaxseed cake serves as a good concentrated feed for livestock. 1 kg corresponds to 1.15 feed units. It contains 6-12% fat and up to 30 (36)% digestible protein.
When processing trusts into fiber, short spun fiber (tow) is obtained, which is used for the manufacture of sack and packaging fabrics, as well as non-spun fiber (tow), which is used to make ropes, twine and as caulking material. Bonfire (stem wood) serves as a raw material in the production of cardboard, ethyl alcohol, acetic acid, acetone and other materials, is used for the production of building boards (fireplates) and insulating materials.
The wood of the stems can serve as organic fertilizer and be used as fuel.
Flax has medicinal value.
The share of flax straw in the yield of fiber flax is 70-75%, and with high yields – about 80%. The share of seeds is 10-15% (in seed crops up to 30%) and the share of chaff is 10-15% of chaff. The output of the trust from the harvest of flax straw averages 70%.
Crop history
Flax is one of the oldest crops of agriculture. It was known in India, China, Egypt, Mesopotamia and Transcaucasia for 4-5 thousand years BC. It is assumed that the birthplace of this culture is Southwest and East Asia, as well as the Mediterranean.
On the territory of Russia, it was grown in ancient times. Back in the XII century. flax was grown in the Novgorod and Pskov principalities. Linen was used to make fabrics and other products that were used not only to meet their needs, but also for exchange. In the XV century. the volume of export of fiber and flax seeds to other countries has reached the largest size. In the XVI century. The first rope factory was built in Russia. In 1711, Peter 1 issued a decree on the expansion of flax sowing, and a little later, a decree appeared on the norms of flax sowing. At the same time, state-owned linen factories were built, producing wide linen sheets for sails and other needs. Until the end of the XVIII century. flax fiber occupied the first place among Russian goods intended for export.
Pskov, Novgorod, Kashin, Kostroma flax were especially known on the world market. At the beginning of the XX century. The Russian Empire was the main supplier of flax fiber.
Prior to the widespread introduction of sunflower in the Russian Empire, oilseed flax served as the most important source of vegetable fat and fodder cake.
Cultivation areas and yield
The area under fiber flax crops in the world in the mid-1980s was 1.5 million hectares, while more than 70% of the world area (1.06-1.1 million hectares) was concentrated in the USSR.
Significant areas of crops are available in the Netherlands, Belgium, France, England, Germany, the Czech Republic, Slovakia, Poland, Romania, and on limited areas also in Canada, the USA and Japan.
The area under oil flax crops in the world was 1.06 million hectares. The share of the USSR accounted for 10% (90 thousand hectares) of the world’s area. Large arrays of it were in Argentina, USA, Canada, India.
Fiber flax is grown in Russia in regions of a humid and temperate climate, oilseed flax – in drier and warmer regions. The main crops of fiber flax are located in the Non-Chernozem zone (Tver, Smolensk, Yaroslavl, Vologda, Pskov, Kostroma and other regions), as well as in Belarus, Ukraine, and the Baltic countries.
In the early 2000s the area occupied by fiber flax in Russia is 120 thousand hectares. During the period from 1970 to 2000, the area under crops was sharply reduced: in 1970, 727 thousand hectares were occupied; 1980 – 595 thousand hectares; 1990 – 418 thousand hectares; 2000 – 108 thousand hectares. The gross harvest of flax fiber also dropped sharply: from 207 thousand tons in 1971-1975. up to 52 thousand tons by the beginning of the 2000s.
Oil flax crops in Russia are located in the Central Black Earth zone, the Volga region, Western Siberia, as well as in Kazakhstan, in the steppe part of Ukraine, in Tajikistan, Uzbekistan, Kyrgyzstan and Armenia.
The yield of flax fiber in 1976-1980 in the USSR, the average was 3.4 c/ha, in 1984 – 3.8 c/ha. In terms of the gross harvest of flax fiber, the USSR ranked first in the world. The maximum yield was obtained in the Pochinkovsky district of the Smolensk region (1983) on an area of 9 thousand hectares and amounted to 7 centners per hectare of fiber and 4 centners per hectare of seeds.
Botanical description
The genus Linum of the Flax family (Linaceae) includes more than 200 species that are distributed in temperate and subtropical regions of all parts of the world. These are predominantly annual, sometimes perennial herbaceous plants.
On the territory of Russia and the countries of the former USSR, 40-45 types of flax are found. Among them, flax is of agricultural importance – Linum usitatissimum L.
According to the modern classification, common flax is divided into five subspecies, of which only 3 are of greatest importance in Russia:
- Mediterranean subspecies – subsp. mediterraneum Vav. et El . Plants are undersized (up to 50 cm). Flowers, bolls and seeds are large. Weight of 1000 seeds 10-13 g. Cultivated in the Mediterranean countries.
- Intermediate subspecies subsp. transitorium ell . Plants of medium height (50-60 cm). Flowers, bolls and seeds of medium size. Weight of 1000 seeds 6-9 g. Distributed as an oilseed crop in the south of Ukraine, in the Crimea, Transcaucasia and Kazakhstan.
- Eurasian subspecies – subsp. eurasiaticum Vav. et El . Plants varying in height and branching. Flowers, bolls and seeds are small. The weight of 1000 seeds is 3-5 g. The most common subspecies in the culture. Cultivated in Europe and Asia.
The Eurasian subspecies is also subdivided into 4 groups of varieties:
- Fiber flax (elongata). Tall (from 60 to 120 (175) cm) single stem plants, branching only in the upper part. Stems are light green or bluish green. Leaves lanceolate, sessile. The flowers are regular, quintuple type, with blue, pink or white petals. Five stamens with blue, orange or yellow anthers. Pistil with five-celled ovary and five styles. The fruit is a five-celled capsule, divided by partitions into ten half-nests. One seed develops in each semi-nest. Seeds are flat, ovoid, brown or brown. On one plant, depending on the density of crops, from 2-3 to 8-10 seed pods are formed. The root system of fiber flax is underdeveloped, it consists of the main tap root and small tender branches located in the upper soil layer, mainly in the arable layer.
Fiber flax is cultivated in areas of moderately warm and humid climate. - Curly flax, or stag (v. brevimulticaulia). A low-growing (30-50 cm) plant with a strongly branching stem at the base and a large number of bolls (from 30-35 to 50-60 or more). Seeds are larger than those of the longweed. The weight of 1000 seeds is about 8 g. It is cultivated for oil production in the countries of Central Asia and Transcaucasia.
- Intermediate flax, or intermediate flax (v. intermedia). Plants of medium height (50-70 cm), 1-2 stems. Usually there are more bolls than those of the long-tailed bat (10-25). More often cultivated for oil, less often for oil and fiber, in the Central Black Earth zone (Kursk, Voronezh regions), in the Volga region (Samara region, Bashkortostan and Tatarstan), partly in Siberia, Ukraine, the North Caucasus, and Kazakhstan.
- Creeping flax (v. prostrata). Plants with numerous creeping stems before flowering. By the beginning of flowering, the stems rise and reach a height of 100 cm or more. It is cultivated as a winter crop in limited areas in Transcaucasia.
Forms of flax determine directions in cultivation: two-sided – for obtaining fiber and seeds (dolguntsy) and seed (curly). Mezheumki occupy an intermediate position, usually approaching curls. In Russia, over 85% of all flax crops fall on fiber flax, or spinning flax.
Technological properties of flax fiber
In the stems of fiber flax, 20-30% is accounted for by the fiber, which consists of fiber (88-90%), pectin (6-7%) and waxy (3%) substances, ash (1-2%). The proportion of fiber in the lower part of the stem is only 12%, and its quality is low (thick, rough, partially lignified). In the middle part of the stem, the proportion of fiber reaches 35% and is of higher quality (thin, strong and long, with the smallest cavities inside and thick walls). In the upper part of the stem, the amount of fiber decreases to 28-30%, the quality is somewhat worse (the fibers have a larger clearance and thinner walls).
Bast fibers are located in the parenchymal tissue of the stem cortex in the form of fibrous or bast bundles, which consist of many individual cells called elementary fibers.
Elementary fibrils are elongated cells with pointed ends 15–40 mm long and 20–30 µm thick on average. The fibers are firmly glued together with pectin into a fibrous bundle. Each bundle can contain 25-40 fibers. Fibrous bundles are arranged in a ring of 25-30 bundles along the periphery of the stem. The bundles, connecting with each other, form a tape of technical fiber.
The length of the bast bundles is determined by the total length of the stem and its technical length, that is, the length from the trace of cotyledon leaves to the beginning of branching (the first branch of the inflorescence). Tall stems are more than 70 cm long, have a greater technical length, contain longer elementary fibers and a longer technical fiber. Thin stems (1-1.5 mm) give a higher quality fiber, since their elementary fibers have thick walls and a relatively small internal cavity, which makes it possible to obtain strong and flexible fibers.
The quality of flax fiber is characterized by technological properties: strength, flexibility, fineness, gloss, elasticity, softness, cleanliness, quality factor and spinning ability. The overall fiber quality rating is determined by comparing the fiber with standard references. The higher the number of flax fiber, the less it is spent on the production of 1 m of fabric. High quality fiber should be long, thin-layered, without a large cavity, smooth and clean.
Biological features
Temperature requirements
Moderate temperatures in spring and summer with intermittent rain and clear weather are favorable for fiber flax. In the conditions of Russia, such conditions are most often observed in the forest zone. Its seeds begin to germinate at a temperature of (2) 3-5 °C. Seedlings are able to withstand frosts down to (-3) -4 (-5) °С. However, at this temperature, damage to the cotyledons and yellowing of the seedling are observed.
Active germination of seeds and the emergence of seedlings are observed when the soil warms up at a depth of sowing seeds to 7-9 °C. The sum of effective temperatures for the period from sowing to germination is -60 °C, from germination to the beginning of flowering – 418-440 °C, from flowering to browning of the bolls – 410 °C (Schegolev). For the entire development cycle of flax, the sum of active temperatures is required from 1000 to 1300 °C.
The optimal temperature for plant growth is (15) 16-17 (18) °C. Hot weather leads to a delay in the growth of stems in height. At a temperature of 22 °C, growth inhibition is already noted, especially with insufficient moisture supply to the plants. Sharp diurnal temperature fluctuations also have a negative effect, especially during active growth (the budding phase).
Oil flax (mezheumok and especially curly) makes higher demands on heat than fiber flax, especially in the ripening phase. They are also more resistant to high temperatures and drought. For curly flax, warm sunny weather with a relatively dry summer (forest-steppe and steppe) is optimal.
Moisture requirements
Fiber flax makes very high demands on moisture. The maximum demand falls on the periods of budding and flowering.
The optimal soil moisture is 70% of lowest soil moisture capacity. At the same time, fiber flax needs moisture in different phases of development.
For swelling of seeds, about 100 (180)% of water is required from their mass. Friendly seedlings appear at an optimum soil moisture content of 10-20 mm in a 10 cm layer. Starting from the fir-tree phase to flowering, fiber flax’s need for moisture increases, while normal plant growth is possible with productive moisture reserves of 30 mm or more in a layer of 0-20 cm.
Flax does not tolerate excess moisture in the soil, as well as areas with a close occurrence of groundwater. Precipitation during maturation is also unfavorable, as this leads to lodging of plants and the development of diseases. During ripening, dry, moderately warm and sunny weather is considered favorable.
The transpiration coefficient of flax is 400-430 (450).
Oilseed flax (curly and mezheumok) is less demanding on moisture.
Soil requirements
More K.A. Timiryazev noted that on fertile soils, flax gives a thinner and more elastic fiber.
Due to the weak assimilation ability of the root system and a short period of intensive growth of stems, fiber flax is demanding on soil fertility.
In the Nonchernozem zone of Russia, well-cultivated, aerated, medium loamy soils and loamy sandy loams with a low degree of podzolization are considered the best. Optimal slightly acidic soil reaction (pH 5.9-6.3 (6.5)).
In fiber flax, up to 80% of the roots are located in the 0-20 cm layer, 14-18% – in the 21-50 cm layer, 3-6% – in the 51-100 cm layer. Therefore, more than 80% of the crop is formed due to moisture and nutrients of the soil horizon 0-20 cm.
Soils with a humus content of at least 2%, easily hydrolysable nitrogen – 10 mg/100 g of soil, potassium and phosphorus 10-15 mg/100 g of soil, and a bulk density of 1.3 g/cm3 are optimal. However, on very rich soils, plants often lie down, on the contrary, on very poor soils they are stunted. Flax can be grown on poor podzolic soils, but in order to obtain stable good yields of high quality (0.6-0.8 t/ha of fiber and 0.4-0.5 t/ha of seeds), it is necessary to choose good predecessors and follow fertilizer systems and plant protection.
Sandy loams and sands are unsuitable for growing fiber flax. Also, it does not work well on heavy clay, cold, swimming and acidic peaty soils. On limed soils, flax produces a brittle and coarse fibre. Does not tolerate weedy soils.
For oil flax, weed-free chernozems and chestnut soils are optimal. Mezheumok and curly are considered less demanding on fertility. Alkaline, as well as heavy clayey and marshy soils, are of little use for their cultivation.
Light requirements
Long-day flax is a long-day plant. In strong sunlight, increased branching of the stem occurs, which leads to a decrease in the yield of long fiber and a deterioration in its quality.
The most favorable diffused light.
Vegetation
Flax is characterized by the following phases of development:
- seedlings;
- the beginning of stalking (“herringbone”);
- budding;
- bloom;
- ripening (sometimes subdivided into fruit formation, seed ripening, full ripeness).
Under favorable conditions, flax seedlings usually appear 5-6 days after sowing.
In the seedling phase, the flax plant has two cotyledon leaves with a small bud between them. In the herringbone phase, the plant reaches a height of 10 cm, while 5-7 pairs of true leaves are formed on the stem. These two phases (approximately 1 month after germination) are characterized by slow growth of the stem in height, but the rapid development of the root system.
Further, flax begins a period of intensive growth of plants in height (gains of 3-5 cm per day). This period lasts 12-20 days and ends with the onset of budding, at the onset of which plant growth slows down to 0.5-1 cm per day, and by the end of flowering almost stops. All agricultural practices aimed at inhibiting this process lead to stem lengthening and fiber quality improvement.
During maturation, the stems of plants are rapidly lignified and seeds are formed in boxes.
According to the Department of Crop Production of the Moscow Agricultural Academy, for the Svetoch variety, the period from sowing to germination is 6-7 days. The fir-tree phase occurs 26-28 days after sowing, budding – after 54-56 days, flowering – after 60-62 days. The growing season lasts an average of 82-84 days. For various varieties, the growing season ranges from 70 to 100 days.
Crop rotation
When using high and intensive agricultural technologies for the cultivation of fiber flax, the predecessors can be winter cereals, legumes, potatoes, corn, sugar beets, a layer or turnover of a layer of perennial grasses.
In Western Europe (Belgium, the Netherlands, etc.), clover is considered a poor predecessor of flax, because due to an excess of nitrogen, it lodges, and the straw turns out to be coarse and branching.
The frequent return of flax to its original place in the crop rotation leads to the accumulation of harmful microorganisms and specific weeds in the soil, which affects the yield. This phenomenon is called “flax fatigue”. They return it to its original place after 7-8 years.
Of great agrotechnical importance are intermediate crops of crops of the Cabbage family (rapeseed, Barbarea, oil radish, etc.), which are used as green manure or for green fodder. These crops are sown after harvesting early cereals.
Fiber flax is considered a good predecessor for winter and spring crops, buckwheat, beets and potatoes.
Falls, a layer of perennial grasses, winter grains, corn, legumes, melons and other row crops are considered good predecessors of oil flax.
Fertilizer system
Flax makes high demands on soil fertility. So, according to numerous data from VNIIL and other experimental institutions, when a complete mineral fertilizer is applied, the yield of fiber flax straw increases by 0.4-0.8 t/ha or 40%, seeds – up to 30%. In addition, the quality of flax fiber is improved.
Flax uses the nutrients of mineral fertilizers in different ways: easily hydrolysable nitrogen is absorbed by about 30-90%, phosphorus – by 10-25%, potassium – by 26-40%; from the soil, respectively: nitrogen – 20-30%, phosphorus – 6-13%, potassium – 12-13%. In conditions of a sufficient amount of moisture in the soil, it is recommended to take the upper gradation.
Nitrogen increases the content of long fiber in the crop. However, its excess lengthens the growing season of plants, leads to lodging of crops and increases the susceptibility to diseases, which ultimately significantly reduces the yield and quality of the fiber. Flax plants are especially sensitive to a lack of nitrogen in the herringbone phase, and the greatest need falls on the period of the herringbone – budding.
Phosphorus is very important from germination to the herringbone phase (5-6 pairs of true leaves). Sufficient phosphorus nutrition accelerates maturation, increases seed and fiber yield. When choosing forms of phosphate fertilizers, it is necessary to take into account their effect on increasing the acidity of the soil, to which flax is very sensitive.
Potassium contributes to an increase in the number of elementary fibers in the stem, increases the yield and quality of flax fiber, reduces the risk of plant lodging, and alleviates the negative effects of excess nitrogen fertilizers. The greatest need for potassium falls on the first 3 weeks of plant growth and in the budding phase.
The removal of nutrients from 1 ton of straw and seeds averages 10-14 kg of nitrogen, 4.5-7.5 kg of phosphorus, 11-17.5 kg of potassium.
On soddy-podzolic soils, the increase in straw yield is 5-7 kg per 1 kg of a.i. fertilizers.
When developing a flax fertilization system, it is necessary to take into account the weak ability of the root system to absorb nutrients from the soil and high sensitivity to high concentrations of soil solution, as well as a short growing season.
The introduction of 30-40 t/ha of manure under previous winter or tilled crops, together with phosphorite flour (400-600 kg/ha) and potassium chloride (150-200 kg/ha), contributes to an increase in yield by 25-30%. Lupins, seradella, vetch and rapeseed, which are grown in stubble crops, can be used as green manure. Manure and composts are not applied directly under flax, as this leads to lodging of crops.
According to the recommendations of All-Russian Research Institute of Flax, 30 kg of nitrogen (or 100 kg/ha of ammonium nitrate) are applied under flax, coming after spring cereals (barley, oats, spring wheat), with their planned grain yield of up to 2.5 t/ha. After cereals with a planned yield of 2.5 to 3.5 t/ha, it is recommended to apply 20-25 kg of nitrogen (or 60-70 kg of ammonium nitrate). With a planned grain yield of more than 3.5 t/ha – 15-17 kg of nitrogen (or 50 kg/ha of ammonium nitrate).
When placing flax after clover, with a hay yield of 3.04.0 t/ha under flax, it is recommended to apply no more than 15-17 kg of nitrogen, and with a hay yield of 4.5-5.0 t/ha, nitrogen under flax is not recommended. The application rate of nitrogen on drained peatlands is reduced, while that of phosphorus and potassium is increased.
The recommended ratio of nutrients in a complete mineral fertilizer for flax is NRK – 1:2:3 on soils poor in nitrogen, and 1:3:4 on soils rich in nitrogen, on poorly cultivated soils – 1:2:2, on medium cultivated soils – 1:3:3, on highly cultivated – 1:4-6:4-6.
In addition to ammonium nitrate, urea, ammonium sulfate or complex fertilizers – nitrophoska, nitroammophoska and ammophos can be applied under flax. 100 kg of nitrophoska correspond to N12-15Р12-15K12-15, nitroammophoska – N16P16K16 (NPK ratio 1:1:1), ammophos – N11-12Р36-52. The application rate of complex fertilizers per 1 ha is determined by nitrogen, and superphosphate and potassium chloride are added to the missing amounts of phosphorus and potassium.
Under flax, in addition to simple superphosphate, double superphosphate (P34-45) and boron superphosphate containing 19-20% phosphorus and 0.2-0.3% boron can be used.
For the rational use of All-Russian Research Institute of Flax mineral fertilizers, it is recommended to apply nitrogen, phosphorus and potassium under flax, taking into account their content in the soil and the planned yield of flax products (table). At the same time, the recommended fertilizer application rates must be adjusted taking into account zonal characteristics.
Table. Approximate norms for applying mineral fertilizers for flax (data from VNIIL, 1984)[1]Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional - M.: Agropromizdat, 1986. - 512 p.: ill. - (Textbook and textbooks … Continue reading
| Very low | ||||||||
| Low | ||||||||
| Medium | ||||||||
| Increased | ||||||||
| High | ||||||||
| Very high | ||||||||
On strongly acidic soils with a pH of less than 5.0, it is better to replace superphosphate with a mixture consisting of three parts of phosphate rock and one part of superphosphate, and on medium acid soils (pH 5.5) – a mixture of equal parts of phosphate rock and superphosphate.
Part of the entire rate of phosphate fertilizers is applied when sowing in rows in the form of granulated superphosphate at the rate of 50 kg/ha for commercial crops and 20 kg/ha for seed crops.
From potash fertilizers for flax, potassium chloride (56-60% K2O), potassium sulfate (48% K2O), potassium salt (30-40% K) can be applied. On sandy soils with magnesium deficiency, it is advisable to apply potassium magnesia (K2O 28-30% and MgO 8-10%).
To correct the developed zonal average fertilizer application rates for flax, All-Russian Institute of Fertilizers and Agrosoil Science is recommended to use correction factors taking into account the planned yield and nutrient content in the soil.
Nitrogen fertilizers for flax are applied in the spring, potash and phosphorus fertilizers – in the fall, before the autumn tillage or immediately after it. On soils with a low content of mobile forms of phosphorus and potassium, as well as on heavy cohesive soils, phosphorus-potassium fertilizers are recommended to be applied in two steps: half in autumn, before autumn tillage, and the second half in early spring, before spring tillage.
The main mineral fertilizer is applied randomly using special fertilizer seeders with ПТХ-4.2А plate-type sowing machines. Granular superphosphate is applied when sowing in rows with combined seeders СЗЛ-3.6.
A good effect is given by fertilizing during the growing season of plants. Ammonium nitrate or ammonium sulfate can be used for top dressing. The consumption rate is N20-30, superphosphate – P30-40, potassium chloride – K30 or complex fertilizers. Top dressing begins to be carried out at a plant height of 6-8 cm or 20 days after germination. A delay in nitrogen fertilization can lead to stretching of flowering time and uneven ripening. Often top dressing is done only with phosphate fertilizers.
Of the microfertilizers, flax needs boron the most. Boron-datolite or boron-magnesium fertilizer is applied in the spring before cultivation at the rate of 20-30 kg/ha (Vavilov; according to other recommendations, 40-70 kg/ha of boron, Kolomeichenko). In addition to these fertilizers, with a lack of boron in the soil, boron superphosphate can be used in rows when sown in an amount of 50 kg/ha. Boron reduces the negative effect of lime on flax plants, reduces damage to plants by bacterial diseases. Boric fertilizers are recommended to be applied on calcareous, podzolic and waterlogged soils, as well as in the development of new lands.
Copper microfertilizers should be used when growing flax on peatlands at the rate of 25 kg/ha of copper sulfate or 250-500 kg/ha of pyrite cinders.
Soddy-podzolic soils of the flax growing zone, characterized by high acidity, are subjected to liming . The experiments of All-Russian Research Institute of Flax showed that with the direct application of lime under flax in small quantities, the yield of flax fiber increases, but its quality deteriorates noticeably. The joint introduction of lime and boron somewhat eliminated the negative effect of lime. For this reason, liming of acidic soils in flax crop rotations is carried out under a cover crop of red clover or in a fallow field. The following lime application rates are recommended for:
- pH 4.5 and below – 2.5-3 t/ha;
- pH 4.6-5.0 – 2-2.5 t/ha;
- pH 5.0-5.5 – 2 t/ra.
Lime is applied using mineral fertilizer spreaders 1РМГ-4, РУМ-8. Errors in the application of mineral fertilizers are not allowed, deviations from the specified application rate should be no more than 10%.
A good effect is given by the addition of mineral fertilizers to the addition of wood ash under flax from 100 kg of ash for every 100 kg of fiber.
Manure or peat-dung compost is usually not applied directly under flax, as this can lead to lodging of plants, variegation and weediness of crops. However, under the conditions of intensification of flax growing, the role of organic fertilizers in flax crop rotation increases. According to studies, it is optimal to apply manure and composts in flax crop rotation in two fields – under potatoes or other tilled crops and under winter or spring crops with oversowing of perennial grasses. At the same time, mineral fertilizers should be applied under crops annually.
According to All-Russian Research Institute of Flax, in order to ensure high yields of all crops included in the flax crop rotation, it is necessary to annually apply at least 10-13 t/ha of organic fertilizers and 1 t/ha of standard mineral fertilizers on cultivated soddy-podzolic soil.
The introduction of organic (20 t/ha manure) and mineral (N30P45K40) fertilizers for oilseed flax significantly increases the yield. In this case, phosphorus-potassium fertilizers are applied under autumn plowing, and nitrogen fertilizers are applied under pre-sowing cultivation. When sowing, it is also recommended to add superphosphate or nitrophoska to the rows at the rate of P15-20, which increases the yield of oilseeds by 0.3 t/ha.
Tillage system
Basic tillage
Due to the underdeveloped root system and the small depth of its penetration into the soil, flax is sensitive to tillage, which largely depends on the predecessor. For varieties of flax (fiber, mezheumok, curly), the tillage system, as a rule, does not differ.
When placing flax after perennial grasses, soil cultivation begins with disking the layer in two directions using heavy disc harrows БДН-3, БДТ-10, БДТ-3.0. Disking is performed 2-3 weeks before autumn processing. Plowing is carried out with plows with skimmers to a depth of 22-25 cm, and in the case of a shallow arable layer – to its entire depth.
The optimal plowing time for the central and western regions of the Non-Chernozem zone of Russia is the end of August – the first half of September, in Western Siberia – August, Belarus – September, the Baltic countries – the end of September – the first half of October, in Ukraine – September. At the same time, good tillage in early spring should be ensured.
When placing flax after grain crops, after their harvesting, the soil is peeled to a depth of 4-6 cm with disk cultivators ЛДГ-5А, ЛДГ-10А, ЛДГ-15А or plowshares ППЛ-5-25, ППЛ-10-25. When infested with couch grass (Elytrigia repens), the depth of peeling should be at least 10-12 cm. The crumbled seeds and knots of couch grass rhizomes quickly germinate and, during subsequent autumn plowing, are deeply embedded in the soil and die. With a strong clogging of wheatgrass, it is advisable to use soil-acting herbicides.
When flax is placed after potatoes, if plowing was carried out after its harvesting, additional plowing is usually not carried out.
On weedy crop rotation landsthey often leave a repair fallow field or carry out autumn tillage according to the semi-fallow type. With semi-fallow tillage, plowing and several cultivations are carried out in autumn to control weeds. Peeling is carried out immediately after harvesting the predecessor to provoke the germination of weeds, which are then plowed. If the fields are clogged with annual weeds, a cultivator of the ЛДГ-10 type is used to a depth of 6-8 cm, when clogged with root weeds, ППЛ-10-25 plow-ploughs are used, with a large distribution of creeping wheatgrass, heavy disc harrows БДТ-3.0 or БДТ- 7.0 in two tracks. In dry autumn weather, it is advisable to aggregate the plow with a ring-spur roller, and in wet weather – with a heavy harrow. Before the start of frost, it is desirable to perform 2-3 cultivations to a depth of 10-14 cm diagonally to the direction of plowing. For cultivation, КПС-4 cultivators with spring paws in combination with harrows are usually used. They try to perform the last cultivation 2 weeks before the onset of frost to a depth of 8-10 cm; at the same time, the same cultivators with lancet paws and without harrows are used.
Pre-sowing tillage
In spring, plowing on sandy and light loamy soils is harrowed, on heavy loamy and moist soils it is cultivated. Pre-sowing treatment of sandy loamy soils is carried out with heavy tooth harrows, light and medium loams – needle-shaped (БИГ-3А) and spring (БП-8), heavy loams and clay soils – cultivators to a depth of 5-7 cm.
Early spring processing of loamy and clayey soils, in case of placing flax after grain crops, is carried out by cultivators with lancet paws to a depth of 5-6 cm with simultaneous harrowing with heavy or medium tooth harrows. When incorporating mineral fertilizers, the cultivation depth on these soils is increased to 10-12 cm.
Early spring processing after a layer of perennial grasses raised in the fall (provided there is no couch grass), in order not to turn the turf to the surface, use disc cultivators ЛДГ-10, ЛДГ-5 or disc harrows БД-10, БДН-3.0 (Vavilov; according to others data, they are treated with cultivators with lancet paws, Kolomeichenko).
Presowing tillage, which is reduced to cultivation with simultaneous harrowing, is carried out one week after early spring tillage. Such treatment promotes more complete germination of weeds , which are then destroyed by tillage implements before sowing flax.
Before sowing, if necessary, the soil surface is leveled, for which light toothed harrows ЗБП-0.6А, plume-harrows ШБ-2.5, etc. are used, or leveling bars are used.
Poorly moistened and light-textured soils are rolled using smooth water-filled (ЗКВГ-1.4) or ringed rollers (ЗККШ-6А). On heavily moistened and heavy soils, it is recommended to carry out leveling with trailing harrows.
When carrying out pre-sowing tillage for flax, combined units are more effective: ripper-leveler – roller РВК-3.6 and leveler-chopper-packer ВИП-5.6, which allow high-quality soil preparation for sowing in one pass.
On well-prepared soils, field germination of flax reaches 70-80%.
Sowing
Seed preparation
Requirements for flax seeds are: purity – not less than 97%, germination – not less than 85%. Seeds should be full-bodied, leveled, shiny, oily to the touch. For fiber flax, contamination with seeds of camelina (Camelina), toriza (Spergula), and chaff (Lolium) is especially dangerous. The admixture of weed seeds in flax seeds should not exceed 180 pieces/kg. Seed material infested with quarantine weeds (for example, dodder (Cuscuta)) is not allowed to be used.
To combat anthracnose, fusarium, rust and other diseases, seeds before sowing or in advance (for (2) 5-6 months) are treated with chemicals using a semi-dry method at the rate of 0.5-1 l of water per 100 kg of seeds. At the same time, the moisture content of the seeds increases by only 0.4-0.5%. For dressing seeds with moisture, fentiuram, fentiuram-molybdate (300 g/100 kg seeds) are used in the form of wettable powders with various adhesive additives. It is also recommended to use preparations: tigam (300 g/100 kg of seeds), 80% TMTD (300 g/100 kg of seeds), granosan with dye (150 g/100 kg of seeds). As adhesives, film-forming substances, for example, sulphite-alcohol stillage or acidic water, can serve. For 100 kg of seeds, take 1 kg of acidic water, 1 liter of ordinary water and a disinfectant according to the norm.
For pickling, special machines such as ПСШ-5, ПС-10А are used.
Before dressing to increase germination energy and field germination, flax seeds 10-15 days before sowing are subjected to air-heat treatment for 4-5 (7) days in open areas or 8-10 days in well-ventilated areas. To do this, they are scattered in a thin layer of 5-6 cm on tarpaulin panels or on clean, dry concrete sites. The seeds are stirred several times a day.
A good result is obtained by seed treatment with microfertilizers (boric acid, copper sulfate, ammonium molybdate, zinc sulfate, etc.).
Sowing dates
Sowing of flax is carried out in an early and short time (within 4-5 days). Sowing begins with the onset of soil ripeness and its heating at a depth of 10 cm to 7-8 ºC. Early sowing helps to increase the yield and quality of the fiber, while reducing the susceptibility of plants to fungal diseases and pests.
Delaying sowing by a week can reduce the yield of fiber and seeds by 10-20%.
According to the data of the Moscow Agricultural Academy Experimental Station for Flax Growing, the yield of trust at early sowing (May 13) of flax was 20% higher than with late sowing (June 9), and the quality of the fiber improved by five numbers. The damage of early crops by flax flea was 2.3%, while that of late crops was 3.46% (Vavilov; according to other sources, 34.6%, Kolomeichenko).
Flax germinated at low temperatures is more resistant to spring frosts. However, too early sowing in cold, wet and poorly prepared soil leads to a decrease in the yield of flax to the same extent as late sowing.
The sowing of oil flax is carried out simultaneously with the sowing of early spring crops.
Seeding methods
The best way to sow flax is narrow-row with a row spacing of 7.5 cm.
For sowing, flax narrow-row seeders СЗЛ-3.6, as well as СЛН-48А, СУЛ-48, aggregated with tractors of the 1.4 kN class are used. For uniform sowing of seeds, seeders are additionally equipped with ring trains.
To obtain flax seeds, wide-row (45 cm) or tape methods (45 × 7.5 × 7.5 cm) of sowing are usually used. For accelerated reproduction of new varieties and in dry conditions, the wide-row method is more effective, while the seeding rate is reduced by 2 times.
For sowing oilseed flax, ordinary grain seeders are used. The sowing method is narrow-row or ordinary ordinary.
Seeding rates
The generalized sowing rate of flax seeds is 20-25 million pieces or 100-120 kg per 1 ha.
Optimal seeding rates largely depend on the variety, for example, for a variety:
- L-1120 – 25-30 million/ha of germinating seeds;
- Svetoch – 27-29 million/ha;
- K-6 – 24-25 million/ha;
- Pskovskiy 359 – 21-22 million/ha;
- Tvertsa – 20-23 million/ha;
- Shokinsky – 25-30 million/ha.
In addition, the seeding rate is determined taking into account zonal conditions, the purpose of sowing.
In wet years, with increased seeding rates, lodging of plants is likely, which makes harvesting and primary processing of flax difficult. Thickened crops are not recommended to be done on poor soils, where flax turns out to be stunted. The seeding rate is increased by 10-15% on heavily weedy fields, as well as on heavy, floating soils, on which a smaller number of plants remain by the time of harvesting.
When growing flax for seeds, the seeding rate is reduced.
The seeding rate for oil flax seeds is 40-60 kg/ha.
With the bilateral appointment of flax-mezheumka (for fiber and seeds), the seeding rate is increased by 10-15 kg.
Seeding depth
The optimal sowing depth of flax seeds on heavy soils is 1.5-2.0 cm, on light soils – 2.0-2.5 cm.
Increasing the sowing depth significantly reduces the seedling density and flax yield. So, in the experiments of Moscow Agricultural Academy and Izhevsk Agricultural Institute at a seed sowing depth of 5-6 cm, the field germination of flax decreased to 42-50%.
The optimal sowing depth of flax seeds for bilateral use is 4-5 cm.
Stubble and joint crops
With the combine method, harvesting with spreading straw on flax, under flax, meadow fescue (16-18 kg/ha) or perennial ryegrass (20-25 kg/ha) can be sown.
White grass clover can be sown simultaneously with flax seeds. To do this, they are thoroughly mixed before sowing.
Seeding quality control
During the first passes of the unit, the sowing depth, the width of the butt row spacing, the seeding rate are checked in accordance with the requirements for the production of mechanized work in field crops.
The number of seeds consumed during the operation of the seeder at the control length of the passage of the unit at a given seeding rate (Q) is calculated by the formula:
Q = LBH/104,
where L is the length of the rut, m; B is the width of the seeder, m; H is the seeding rate, kg/ha.
Crop care
Care of crops of commercial fiber flax consists in:
- post-sowing rolling;
- harrowing (during the formation of a crust);
- weed and pest control.
The listed agrotechnical measures are carried out taking into account specific conditions.
Harrowing to destroy the soil crust is carried out with light sowing, rotary or mesh harrows, as well as ring-spur rollers.
In addition to agrotechnical measures, the most important methods of caring for crops include the use of chemical means to control weeds, pests and diseases of flax. The damage they cause to fiber flax can reach 30% or more in some years.
According to All-Russian Research Institute of Flax data, in the presence of more than 200 dioecious weeds per 1 m 2 of crops, it leads to a decrease in yield even when fertilizers are applied.
To combat annual dicotyledonous weeds (white gauze (Chenopodium album), field yaruka (Thlaspi arvense), zebra pickle (Galeopsis speciosa), field tori (Spergula arvensis), wild radish (Raphanus raphanistrum), etc.), spraying with herbicides such as 2M-4X, 2M-4X 80%, which are applied in the amount of 0.6-1.2 kg. The consumption of the working solution when spraying with ОН-400 boom sprayers or others is 200-300 l, with the help of aircraft – 150-200 l/ha.
The optimal phase of development of flax crops for herbicide treatment is plant height from 5 to 8 (15) cm (herringbone phase). During this period, the leaves are located on the stems at an acute angle (10-30°) and are often covered with a wax coating, thus significantly reducing the negative effect of the herbicide on cultivated plants in comparison with the treatment at a later date.
The greatest effect of spraying crops is achieved in clear and dry weather at an air temperature of 15-17 °C. Cool weather (12 °C) slows down the penetration of the herbicide solution into weeds, while dry and hot weather increases, but at the same time causes flax to stick.
According to All-Russian Research Institute of Flax, the use of herbicide 2M-4X (0.75 kg/ha) in a mixture with ammonium nitrate (9 kg/ha) or urea (13 kg/ha) promotes good growth of flax and more complete cleansing of crops from weeds. the use of herbicide and nitrogen fertilizer , compared with treatment with one herbicide, increases the yield of flax seeds by 13-14% and fiber – by 12.8-27.7%.
According to the Department of Crop Production of the Moscow Agricultural Academy, the effect of spraying crops with herbicide 2M-4X (0.5 kg/ha) in a mixture with ammonium nitrate (12 kg/ha) is enhanced if microfertilizers are added to the mixture (boron 0.25 kg/ha, zinc and molybdenum at 0.1 kg/ha). At the same time, the fiber yield increases by 0.15-0.2 t/ha, seeds – by 0.13-0.15 t/ha. Such a joint action of the herbicide, ammonium nitrate and microfertilizers is associated with an increase in plant photosynthesis. In addition, the infection of flax with bacteriosis, fusarium, rust and other diseases is noticeably reduced.
Particular attention in flax-sowing farms should be given to the fight against creeping wheatgrass (Elytrigia repens), which in heavily infested areas can reduce the yield of flax fiber by 20-25% or more. Sodium trichloroacetate (TCA) is used to control this weed. The drug is applied no later than the first half of September, as wheatgrass “shilets” appear after peeling the soil from under grain crops or disking a layer of perennial grasses. The application rate of sodium trichloroacetate on sandy loamy soils is 20 kg/ha a.i. (or 23 kg/ha 90% of the preparation), on loamy soils – 30 kg/ha a.i. (or 34.5 kg/ha of 90% preparation). The same doses are used after autumn treatment.
According to the results of VNIIL experiments, the application of 30 kg/ha of sodium trichloroacetate before plowing leads to the death of 78.1% of the rhizomes of couch grass, and the increase in fiber yield reaches 13.6%, seeds – 10.8%.
Another notorious flax weed is flax chaff (Lolium remotum). Against it, the herbicide 40% triallat is used, which is applied 1-3 days before sowing or on the day of sowing before leveling the soil surface with harrows at the rate of 1.5-2.5 kg per 1 ha. Triallat reduces the infestation of flax seeds by chaff by 90-96%.
Care of flax crops should include the protection of plants from pests, especially the ubiquitous flax flea. Against the flea, 1-2 days before the emergence of seedlings, marginal and blockade treatments of crops with insecticides are carried out to a width of 3-4 passes of the unit. For processing, the preparation phosphamide Bi-58 is used in the amount of 0.8 kg/ha. For these, 80% chlorophos (0.8 kg/ha) can also be used.
When the number of flax fleas is more than 10 individuals per 1 m 2 in dry and hot weather, or more than 20 individuals per 1 m 2 in wet weather, the treatment is performed using boom sprayers. Fluid consumption 200-300 l/ha.
To control thrips, crops are dusted with 12% HCH dust (15-25 kg/ha) after the herringbone phase.
Harvest
The ripeness phase of fiber flax is divided into four phases:
- green;
- early yellow (early);
- yellow;
- complete.
Green ripeness (flax-green) comes after flowering. During this period, the stems and boxes are still green, only the leaves in the lower third of the plant begin to dry out and turn yellow. When the seeds are crushed, a milky liquid is released from them. Harvesting flax in the green ripeness phase produces a thin and shiny, but weak fiber. Such fiber can be used in the production of thin products (cambric, lace).
In the phase of early yellow ripeness, the leaves of the lower half of the plant stem fall off, the rest, with the exception of the apical ones, turn yellow. The boxes have green veins. Seeds in pods acquire a green-yellow color and a yellow spout (wax ripeness). Harvesting flax in this phase produces the best quality fiber: soft, silky and strong.
In the phase of yellow ripeness, all leaves turn yellow, remain only at the top of the stem, the bolls become brown, the seeds become light brown. Usually occurs 5-7 days after the early ripeness phase. The quality of the fiber in the phase of yellow ripeness begins to decline. The fiber of the lower part of the stem becomes coarse.
In the phase of full ripeness, all the leaves fall off, the stems and boxes become brown. The fiber collected in this phase is of poor quality: dry, hard, inelastic.
For timely harvesting of flax it is possible to use desiccation. This technique allows you to dry the plants on the vine and refuse field drying and ripening of plants in sheaves. Desiccation is carried out in the phase of early ripeness.
The harvesting of fiber flax by harvesters usually begins 2-3 days after the onset of the phase of early yellow ripeness (Karpets, 1984). Linen harvested during this period produces the greatest amount of high quality long fiber. Seeds by this moment are sufficiently formed and after ripening can be used for sowing (technical ripeness of flax).
Harvesting of flax in the phase of yellow ripeness is carried out upon receipt of seeds of breeding varieties of fiber flax in seed farms. In the phase of full ripeness, oil flax is harvested.
The period of technical ripeness of fiber flax is 8-10 days, but in hot weather it can be reduced. Therefore, the delay in pulling leads to significant yield losses: on average, for each day, the loss of fiber is 2-3%, seeds – 1.5%.
According to the data of the Moscow Agricultural Academy Experimental Station for Flax Growing, harvesting flax at the end of the yellow ripeness phase led to a decrease in the yield of long fiber by an average of 14.2% over 5 years compared to harvesting in the early yellow ripeness phase, and harvesting in the full ripeness phase by 21. 9%.
Flax harvesting is considered the most difficult and time-consuming work in flax growing – it accounts for 70-80% of all costs. Therefore, the use of efficient flax harvesting technologies is of great industrial and economic importance.
The traditional sheaf harvesting method, including pulling, field drying of sheaves in pasterns, threshing on threshing machines and manual spreading in the meadow, does not meet the objectives of the development of flax growing. A more advanced and efficient way of harvesting flax is the well-developed and proven for many years combine harvesting method.
The combine harvesting method allows you to perform several operations: pulling, stripping seed pods, loading a heap of vehicles, knitting flax straw into sheaves using a knitting machine for subsequent delivery to a flax mill (ЛКВ-4А combine) or spreading it on a flax in the form of a tape to obtain trust (harvester ЛК-4А).
Compared with the sheaf method, the combine method reduces the time for harvesting flax by 3-4 weeks, and labor costs – when spreading straw on a flax bed by 1.5-1.7 times or when putting straw in sheaves by 3-4 times. The efficiency of the combine harvesting method increases when several combines are used.
According to All-Russian Research Institute of Flax, the preparation of flax straw on a flax bed is almost comparable to the process of its maturation on meadow beds. Conditions on the flax can be improved by overseeding flax with perennial grasses ( meadow fescue , perennial ryegrass, white clover, etc.). The quality of trusts in this case increases by 1-2 numbers.
When harvesting flax with the help of ЛК-4А combines, the spreading of straw on the bed is carried out simultaneously with harvesting in the optimal agrotechnical terms – 20-30 days earlier than with the sheaf method.
In the process of straw maturation, approximately every 8-10 days it must be turned over with the help of mounted turners ОСН-1 for uniform maturation and prevention of overgrowing of straw with grass. The trust begins to rise when its moisture content is not more than 20%.
The lifting of linen stock with its tying into sheaves is carried out by a mounted pick-up ПТН-1. The use of a pick-up allows you to reduce labor costs compared to the manual method by 6 times.
With a combine harvesting method, a raw heap is obtained, which consists of 52-84% of boxes, 2-7% of seeds, 12-16% of mud and other impurities. The humidity of the heap is usually high – 60-65%, seed pods 40-50%. In order to prevent damage to seeds in boxes, a heap is evenly loaded into the drying sections with a layer of 1.1 m in floor dryers or 0.7 m in conveyor dryers and is immediately dried to a moisture content of 16-18% on the surface, for which installations are used, for example, ОСВ-60 with air heater ВГ1Т-400 or ВПТ-600. The temperature of the heated air should not exceed 45 °C. After 20-45 hours of drying, cold air is blown for 1.5-5 hours to reduce seed damage during heap processing. The following requirements are imposed on the process of drying and processing: loss of seed germination should be no more than 2%, crushing – less than 1%, irretrievable losses during processing should be no more than 3%. The threshing of the heap is carried out on a threshing fan МВ-2.5А. Seed moisture before threshing should be 10±2%.
In the culture of fiber flax, it is of great importance to bring the seeds obtained during harvesting to sowing conditions. To do this, farms carry out their cleaning on grain cleaning wind screen machines СМ-4, СОМ-300 and electromagnetic machine СМЩ-04. At flax seed stations, production lines from a complex of machines and equipment for processing and preparing seeds for sowing are used for this.
Compliance with the technology of drying seeds intended for sowing is important, since the loss of germination occurs due to the death of the embryo under the action of a heating temperature above the maximum allowable. The sensitivity of the embryo to high temperatures increases with increasing seed moisture. For shaft-type dryers, the optimal drying modes are determined (table).
Table. Recommended modes of drying flax seeds[2]Crop production/P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional - M.: Agropromizdat, 1986. - 512 p.: ill. - (Textbook and textbooks for … Continue reading
Flax straw can remain on the farm for primary processing or be immediately delivered to harvesting stations and flax mills. For delivery to flax mills, straw must comply with the established requirements (GOST). The sheaves must be round or oval in shape with a diameter of at least 13 cm. The moisture content of the straw (to an absolutely dry mass) must be 19%, straw with a moisture content of more than 25% is not accepted by flax mills. Permissible weediness – 5%, with more than 10% weediness, straw is also not accepted.
The quality of flax straw is determined by the length (handful), strength, bast content, suitability, color, stem diameter. Depending on these properties, it may have the following numbers: 5.00; 4.50; 4.00; 3.50; 3.00; 2.50; 2.00; 1.75; 1.50; 1.25; 1.00; 0.75; 0.50. The quality of delivered straw is assessed in daylight by comparing the selected samples with seasonal standard samples.
Primary processing of flax
In order to reduce losses and obtain the greatest amount of high-quality fiber from straw, it is divided into 2-3 grades according to length, thickness, color and other qualities. Plants affected by diseases are isolated in a separate fraction.
The main operations of primary processing of flax include:
- preparation of trust straw by spreading or rinsing;
- drying trusts;
- wrinkle;
- fluttering.
At present, 75-80% of the trusts are prepared on farms by spreading straw on the beds. The industrial technology of fiber flax cultivation provides for the sale of 50-70% of flax products to flax mills in the form of flax straw. Flax straw, when spreading, turns into trust under the action of an aerobic fungus – Cladosporium herbarum Zin. (aerobic straw lobe). The trust is best aged when spreading in August, when the weather is warm (18 °C) and humid with heavy dews. The duration of maturation under such conditions this month is 3-4 weeks, in later periods of spreading it increases to 5-7 weeks. By the end of the maturation, the stems of the trusts become gray. At this time, to determine the end of aging, sampling is carried out – “torture” (handfuls from different places, at least 2 kg). The samples are dried, processed on a pulper and ruffled.
2-2.5 tons of flax straw are spread on 1 hectare. Trusts from such straw are obtained by 20-25% less (slate trust).
After aging, the trust is placed in cones to dry. In case of rainy weather, drying is carried out in special dryers and rigs.
The best way to obtain trusts is considered to be a water soak of straw in special soaks, and especially in warm water (thermal soak).
Thermal urine is carried out in installations consisting of several soaking pools, devices for heating water and other equipment. The decomposition of pectin substances in the water lobe occurs under the action of anaerobic bacteria Bacillus felsineus Carbone, Granuiobacter pectinivorum Bejerinc et Van. and others (anaerobic lobe of flax straw).
Wetting basins are loaded with sheaves of straw in a vertical position and immediately filled with water at a temperature of 36-38 °C. After 9 hours, part of the urination liquid is drained, fresh warm water is added instead. 6 hours later, a slow flow of warm water is established through all pools until the lobe is completed. The duration of the heat lobe is 3-5 days. Upon completion, the trust is washed with water, squeezed on presses and dried.
Dew or water lobe, as well as chemical treatment in alkaline solutions, can also be used to isolate the fiber.
To isolate pure fiber from trust, it is necessary to remove the fire, that is, the wood of the stems. This operation is carried out with the help of special roller mills. After that, raw fiber is obtained, which is subjected to additional separation from the remains of the fire on scutching machines.
After drying, the trust (slate and monets) is subjected to crushing on МЛКУ-6А pulpers, from which fiber is obtained. The fiber is subjected to processing – scutching – on flax scutching machines ТЛ-40А. On average, flax fiber contains 25% of the total fiber, long – no more than 18-20%. Part of the fiber goes to waste, from which, with the help of tow-making machines КЛ-25А, a short “tow” fiber is obtained. Usually, all these machines are part of one scutching and scutching unit, the daily output of which is 600-800 kg of fiber.
When handed over to flax mills, the trust must be gathered into sheaves of hand or machine knitting. The sheaves should be uniform in length and degree of maturation or soaking, and the stems in the sheaves should be placed with butts in one direction. The moisture content of the straw should be no more than 20%, weediness – no more than 5%, fiber content – no less than 11%, sheaves diameter – no less than 17 cm.
Linen weed (soaked straw), depending on the fiber content, strength, handful length, suitability, color, separability and diameter of the stems, is divided into numbers: 4.00; 3.50; 3.00; 2.50; 2.00; 1.75; 1.50; 1.25; 1.00; 0.75; 0.50. In accordance with the technical specifications (GOST), an OOV device should be used to determine the fiber separability, to determine the fiber content – ПК-2, sheaf length – ДЛ-3.
Linen fiber, upon delivery to procurement points, should be tied into waders of 3-4 kg with a flax length of up to 70 cm. At a distance of 1/3 from the top, each wader is tied twice with a belt made from the same fiber. Rated humidity of torn flax to absolutely dry mass should be 12%. Upon acceptance, an organoleptic analysis of ragged flax is carried out by comparing it with standard seasonal samples. Worn flax, depending on the quality, is usually divided into numbers: 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 28, 30, 32. Linen the fiber should be clean from the fire, strong, long, thin, soft, greasy to the touch, heavy and uniform in color (light silver, white). The yield of pure fiber is usually about 15% by weight of straw or 20% by weight of straw.
Industrial technology of fiber flax cultivation
All-Russian Research Institute of Flax, together with the Ukrainian Research Institute of Agriculture and the Belarusian Research Institute of Agriculture, developed an industrial technology for the cultivation of fiber flax, which was introduced on more than a quarter of all commercial crops. The technology is designed to produce at least 550-800 kg/ha of flax fiber and 500 kg/ha of seeds, in addition to reducing labor costs by more than 2 times.
Industrial technology includes:
- concentration of crops in fiber flax farm in 2-3 crop rotations;
- placement of flax after cereal crops;
- introduction of scientifically based norms of mineral and organic fertilizers in
- the crop rotation;
- basic tillage according to the semi-fallow type;
- improved pre-sowing tillage;
- sowing at the optimal time with seeds of class I and II with a seeding rate of 18-22 million/ha of viable seeds;
- application of an integrated system of measures to combat diseases, pests and weeds;
- pre-harvest desiccation;
- mechanized cleaning;
- implementation of at least 50% of the crop in the form of straw according to the “field-factory” scheme. At the same time, as the experience of All-Russian Research Institute of Flax has shown, the roll cleaning technology deserves attention.
Organizational measures are based on the contract, the creation of harvesting and transport complexes for harvesting flax in the optimal time and reducing the loss of flax products.
Technological operations are recommended to be performed by machines for:
- dressing seeds ПСШ-5, ПС-10А, ОПШ-15;
- fertilizer application – ПОУ, РТТ-4.2А, 1-РМГ-4, ЛДГ-10А, ЛГД-15А, БД Т-3, ПЛН-8-40, ПЛН-4-35, ПЛН-3-35, КПС-4-03, ЗКВГ-1,4, РВК-3,6;
- sowing – СЗЛ-3,6;
- cleaning – ЛК-4А. ЛКВ-4А, ПТН-1, ОСН-1, ПНП-3, ПСП-3, ВПТ-600, ТЛН-1.5А, Т-25А, МТЗ-80, ТАУ-1,5, МВ-2.5А, МЛ-2.8П, trailer 2ПТС-4М.
Thus, intensive technology, using intensification factors, and, despite the significant costs of fixed assets in the development of technology, allows the most rational use of resources and obtaining flax products with greater efficiency.
For example, in the collective farm “Bolshevik” of the Torzhok district, according to the industrial technology of flax in 1983, 9.2 centners per hectare were obtained from a total area of 330 hectares with labor costs for obtaining 100 kg: seeds – 12.2 man-hours; straw – 2.5 man-hours; trusts – 5.3 man-hours
Features of agricultural technology of oil flax
Oilseed flax is placed in a crop rotation after fertilized winter crops, perennial grasses, legumes, corn, potatoes and other crops.
Autumn processing is carried out as early as possible, before which it is recommended to peel the soil. The main tasks of spring processing include the preservation of moisture in the soil and weed control.
When fertilizing oilseed flax, phosphorus and potash fertilizers (30–45 kg/ha of phosphorus and potassium) are applied for autumn tillage, and nitrogen fertilizers (25–30 kg/ha of nitrogen) for presowing cultivation. According to All-Russian Research Institute of Oilseeds data, the introduction of granular superphosphate into the rows during sowing gives a good result. Seed yield increases by 2.9 kg/ha.
Sowing of oil flax is carried out simultaneously with early spring crops. The sowing method is the usual ordinary or narrow-row. On weedy soils, wide-row sowing is used with row spacing of 45 cm. The seeding rate is from 30 (on wide-row) to 80 kg/ha. With double-sided use of flax (for seeds and fiber), the seeding rate is increased by 10-15 kg. Sowing depth 4-5 cm.
Oil flax is harvested for seeds in the phase of full ripeness. Cleaning is carried out by grain combines. With two-sided use of the crop – in the phase of yellow ripeness with a cut height of 10 cm and a reduced number of drum revolutions per minute to 800-1200. If flax straw is spread on a flax field, the bottom of the stacker is removed from the combines. If the straw is spread elsewhere, the harvester collects the straw into piles and then it is transported to the meadows and spread over the surface with a layer of no more than 15 cm. In damp and warm weather, flax stalks can mature for 10-12 days.
The separation of fiber from the trust is carried out with the help of mills and shakers (construction tow). To isolate the spinning fiber, a tow-making machine КЛ-25А is used.
Sources
Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).
V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.
Fundamentals of agricultural production technology. Agriculture and crop production. Ed. V.S. Niklyaev. – M .: “Epic”, 2000. – 555 p.