Buckwheat is an agricultural groats crop.
- Economic importance
- History of crop
- Cultivation areas and yields
- Botanical description
- Biological features
- Crop rotation
- Fertilizer system
- Tillage system
- Crop care
- Post-mowing and stubble crops of buckwheat
- Progressive cultivation technology
Buckwheat grains are used to produce buckwheat groats that have high taste and nutritional qualities. The protein composition of buckwheat corresponds in quality to that of leguminous crops and includes essential acids lysine – 7.9% and arginine – 12.7%.
The chemical composition of not husked fruits: moisture – 12.8%, protein – 10-16%, fat – 1.8-2.7%, nitrogen-free extractive substances – 60-62%, fiber – 13.3%, ash substances – 2.1%.
Buckwheat grits contains organic acids (citric, apple, oxalic acid), minerals (phosphorus, calcium, iron, copper), vitamins B1 (thiamine), P (rutin) and B2. The content of vitamins is 1.5 times higher than in groats of millet. That is why buckwheat refers to one of the best dietary products.
Buckwheat flour is not suitable for baking, but is used for baking pancakes, cakes, etc., as well as in the confectionery industry. Waste after husking grains, straw and chaff are used as livestock feed, bedding or organic fertilizer. 1 kg of buckwheat straw contains 23 g of digestible protein and is equal to 0.3 fodder units, but its excess in the diet of animals is undesirable, since it can lead to diseases. Green mass obtained in stubble crops is suitable for ensilaging.
Ashes of buckwheat straw and husks contain up to 35-40% potassium oxide, so it can be used as a potassium fertilizer (potash).
Buckwheat is a honey-making crop, the collection of honey from 1 hectare of crops amounts to 100 kg.
From the leaves and flowers of buckwheat are obtained the medicinal drug rutin, used in the treatment of sclerosis, hypertension, as well as for the removal of radioactive nuclides from the body. The substance rutin is also present in the kernel.
It is a good precursor for many crops, also because of its fast growth and good weed suppression.
Its short vegetation period and late sowing ability allow it to be used as a stubby crop, a cover crop and as an insurance crop. The fallow crops can be ploughed for green fertilizer.
History of crop
Cultivated buckwheat comes from the high humid regions of the eastern part of the Asian continent (India, China, the Himalayas), formed as a crop about 2.5 thousand years ago. Its origin determines its specific morphological properties and requirements for growing conditions.
Probably the cultural buckwheat originated from the wild buckwheat Tatar (Fagopyrum tataricum). It came to the territory of the south of modern Russia in the I century A.D., but it began to be cultivated only in the XIII-XV centuries. At the same time, it also spread to the states of Europe.
Cultivation areas and yields
Russia is one of the world’s top producers of buckwheat. In the USSR the area of buckwheat crops in 1971-1975 was 1.75 mln ha. In the Soviet Union buckwheat was planted on 1.75 mln ha in 1971-1975, and in 1976-1980 – on 1.58 mln ha. – In 1976-1980 buckwheat was planted on 1.58 million hectares. In Russia at the end of the 90s buckwheat was cultivated on 1.0-1.5 million hectares, or 2.2 percent of the total area of cereals. The gross yield was 0.5 million tons with yields of 0.4-0.6 t/ha.
Global cultivated area was about 3.9 million hectares (0.6% of grain crops area), including 2.4 million hectares in Europe and 0.6 million hectares in China. There are also small areas in Canada, USA, Japan and India. Tatar buckwheat is cultivated in the high altitude areas of the Himalayas at altitudes up to 4.5 thousand meters.
The gross yield of grain in the world is 4 million tons or 0.2% of grain production. The average yield is 1.0 t/ha.
The main buckwheat crops in Russia are located in the central regions of the Non-Black Earth and Black Earth zones, in the Volga region, in Tatarstan, Bashkiria and Udmurtia, in the Urals, in Siberia and the Far East. In the south and southeast of the country, this crop is not common because it suffers from drought and heat. Of the former Soviet Union countries, buckwheat is cultivated in Belarus, the forest-steppe and western parts of Ukraine, and Kazakhstan.
Buckwheat yields in 1976-1980 averaged 0.57 t / ha, in advanced farms with high agrotechnics and taking into account the biological characteristics of culture – up to 2.0-2.5 t / ha grain. For example, in 1975 in Bugulma district of Tatarstan (state farm “Vostochny”) the yield reached 3.22 t/ha, in 1982 Aznakeevsky district of Tatarstan (collective farm “Avangard”) – 2.26 t / ha, Bershadsky district of Vinnitsa region (collective farm named after XXII Congress of the CPSU, Ukraine) – 2.13 t / ha, in Izbulek district of Bashkiria (state farm “Novomikhailovsky”) – 2.1 t / ha, in Skopinsky district of Ryazan region (collective farm “Svetly Put”) – 2.0 t / ha.
The concentration of crops, qualification of specialists and specialization of farms are important in increasing the yield and efficiency of buckwheat cultivation.
Among cereals buckwheat is characterized by unstable and low yields. However, in a market economy it becomes a relatively profitable crop.
Buckwheat (Polygonum fagopyrum) belongs to the Buckwheat family (Polygonaceae). It is represented by species:
- cultivated buckwheat (F. esculentum Moenh.), an annual herbaceous plant, subdivided into:
- common (ssp. vulgare Stol.) – most common in culture;
- multifolium (ssp. multifolium Stol.) – high-growing, well foliated, grown in the Far East;
- Tatar buckwheat (F. tataricum (L.) Garth.) – is a wild annual plant, often referred to as a weed.
Cultured buckwheat has the greatest interest and distribution, the other species are of interest more for breeding.
In 1995 the Japanese researcher O. Ohnishi proposed a new classification of buckwheat, which included 16 species.
The root system of buckwheat is taproot, consisting of a germinal root and secondary roots. It can penetrate to a depth of 60-100 cm. The main mass lies at a depth of up to 30 cm. Roots are poorly developed: according to A.P. Modestov’s data, their length is 2 times less than that of oat plants.
Roots are able to secrete formic, acetic, citric, oxalic acids, which determines the ability of buckwheat to assimilate nutrients that are hardly soluble. Long root hairs also contribute to this absorption capacity.
At the beginning of flowering, 50% of the root system becomes brown, and by full flowering 75% of it is associated with early aging. Shallow seed embedding and drying of the topsoil lead to poor development of adventitious roots, which, in turn, reduces the productivity of buckwheat.
The stem is hollow, ribbed and branched, forming up to 10-12 branches, 50 to 120 cm high, sometimes up to 2.5 m, it turns red at maturity.
The buckwheat stem is divided into three parts:
- lower, or subcotyledonous knee, from which stem roots are formed;
- middle, or branching zone, from which branches of the first order depart, and at rare sowing, branches of the second, third and higher orders depart from it as well. In thickened ones there is no branching; the flower stalks are located only at the top of the stem;
- upper, or fruiting zone, where generative organs are formed.
Leaves are petiolate, heart-shaped-triangular, becoming sessile and arrow-shaped toward the top of the stem and branches.
Buckwheat plants develop a large leaf surface, but the leaf supply per flower, which is 0.56-0.62 cm2, is 1.5-2 times lower than that of spring wheat. By increasing the feeding area from 15×5 cm to 30×15 cm the leaf surface of one flower increased from 0,5 to 0,96 cm2, while the productivity of a plant increased from 1,3 to 11,4 g (G.M. Solovyov). Therefore, buckwheat yield is determined by leaf supply of flowers and illumination, which is conditioned by feeding area.
Buckwheat flowers are axillary, aggregated in inflorescences (axillary brushes), have a strong odor that attracts insects, are white, pink or red in color, and have different structures. The number of flowers on one well-developed plant ranges from 500 to 1500. Flowers are dimorphic, heterostyled, i.e., some plants have short-stalked flowers with long stamens, while others have pistils about twice as long as stamens. The ratio of plants with long-staminate and short-staminate flowers in crops is about equal. The phenomenon is called dimorphism.
The fruit of buckwheat is a trihedral, filmy, gray, brown or black nut with a pericarp attached to the seed. The weight of 1,000 seeds varies from 18 to 32 g, and the filmy weight is 15-30%. The germ mass is 10% of the seed weight. The seed consists of two cotyledons, which are brought to the soil surface, a root, and an endosperm.
Seeds begin to germinate at 7-8°C. Uniform sprouts appear at 15°C in 7-8 days, at 12°C in 10 days. The temperature limits of growth and development are compressed.
Spring frosts as low as -1.5°C can damage seedlings, while they die at -2°C. At temperatures less than 12-13°C, buckwheat growth is severely slowed. Temperatures above 25°C also have a depressing effect, especially during the flowering phase. At this time, plants may suffer from dry and cold rainy weather, with nectaries becoming weakly active, and nectar dries out.
Air temperatures close to 20°C (18-25°C) are considered optimal for buckwheat. During flowering, warm weather with alternating cloudiness, a temperature of 20-25°C, relative humidity of at least 60% and little wind is beneficial. Such weather contributes to nectar production by the flowers.
Buckwheat is a water-loving plant. Water consumption is 2-3 times higher than that of millet. Transpiration coefficient is 480-600. The critical period is from flowering to fruit ripening.
Seed germination begins when 40-50 % of the seed mass is absorbed. Water consumption during the period from seedlings to flowering is 11%, and from flowering to ripening it is 89%.
Buckwheat yields most in warm, moderately humid years, particularly during the second vegetation period. Under dry conditions, the yield decreases sharply.
Buckwheat is a short-day plant. It grows and develops well under 17-19 hours of light during the day. Short daylight hours and late sowing lead to a shortening of the growing season, but the plants are stunted, especially the late-ripening forms. Researchers I.A. Pullman, G.G. Akshrunov, and K.A. Savitsky found that variable cloudiness is favorable for high yield formation.
Buckwheat is little sensitive to soil acidity; the optimum pH is 5-7.5. Experiments of O.K. Kedrov-Zikhman showed that buckwheat yield at pH 4.78 was 32.5 g/unit, at pH 5.3 – 53.5 g/unit, at pH 7.15 – 55.7 g/unit.
It develops well on different types of soils, including cultivated peaty and sandy soils, but prefers more fertile ones, such as loose fertile chernozems and gray forest soils. Poorly tolerates over-watered lowered areas.
The growing season is 60-100 days.
Phenological phases of vegetation:
- germination – comes 2-4 days after sowing and seed swells;
- sprouting occurs 7-10 days after sowing; the cotyledon sprouts and bears the seeds to the soil surface;
- first pair of true leaves;
- branching sets in 8-10 days after the shoots, the second leaf is formed, the buds are put in the axils of the leaves, from which the branches develop;
- budding starts 8-17 days after shoots appearing, almost simultaneously with the branching;
- flowering begins, depending on the precocity of the cultivar on 18-28 days after sprouting in inflorescences of the main stem, in 4-8 days on the side branches, the duration of 35-45 days;
- fruit formation – extended up to 30 days;
- ripening – the ripening of the first fruits begins 25-35 days after the beginning of flowering. When dry weather alternates with rainy weather, there may be secondary formation of new fruits.
From sprouting to budding, buckwheat plants grow slowly. From budding to the beginning of seed browning, growth is vigorous, accumulating over 70% of total dry matter. After growth slows down, but does not stop, continuing until the ripening phase. Simultaneously with intensive growth, early development of flowers and fruits is observed.
The ripening phase corresponds to increased requirements for nutrients and other growth factors. External conditions during this period are crucial for the formation of the crop.
At 35-40% moisture content the increase in grain weight stops, the water content in the leaves and stems during this period reaches 50-65%. Fruit ripening begins in the lower tiers of the central and lateral stems.
Pollination is cross-pollinated, mainly by insects, partly by the wind. Fertilization and grain set occurs better if pollen from long-stamen flowers falls on long styles and pollen from short stamens on short styles. This type of pollination is called legitimate, or legal, or single-type pollination. Conversely, when pollination of long styles by pollen from short stamens, and pollen from long stamens on short styles, is more effective, it is called illegitimate pollination, or illegal pollination.
Studies conducted at the Moscow Agricultural Academy showed that the fruit setting rate of buckwheat cultivar Bolshevik averaged 5% with self-pollination, 9.6% with illlegitimate pollination, and 43% with legitimate single-type pollination.
Buckwheat is a cross-pollinating plant. Most of the pollen is carried by insects, mainly bees. Usually the number of fertilized ovaries is less than 20%. This amount is negatively affected by high or low temperatures, drought, wind, precipitation, and fog. Under extreme conditions, flowering may stop completely. In cases where rainy weather sets in after a drought, buckwheat is able to return to growth, flowering, and formation of a full crop.
Proper farming techniques and bee pollination help to increase the percentage of fertilization of ovaries.
The main causes of yield instability include:
- overlapping in time of vegetative and generative periods;
- violation of the relationship between the leaf surface and the number of flowers on one plant;
- long periods of flowering and fruiting.
After row crops, winter and leguminous crops, buckwheat yield increases by 15-40% compared with spring cereal predecessors. In rotations with spring cereals it is better to put buckwheat after wheat. Good predecessors also include perennial grasses, in dry conditions of the Volga region – bare fallow.
In the southwestern regions of Russia and Ukraine buckwheat serves as a good predecessor of winter crops. For example, at the Sumska Agricultural Experimental Station winter rye with buckwheat fallow gave 2.12 t/ha of grain (buckwheat yield in fallow was 1.44 t/ha), after pure fallow – 2.95 t/ha.
In areas with a long warm autumn and with sufficient precipitation buckwheat is used for stubby crops. It is placed after crops that release the field early, for example, after winter rape, barley, rye, early potatoes. Buckwheat is used as an insurance crop in case of winter or early spring crops failure.
Buckwheat may be sown in plots located near forest strips and forests, especially in steppe and forest-steppe zones, since they are well protected from wind, have greater soil and air humidity, as well as a greater number of insect pollinators. For example, at the Chishminskaya experimental station (Bashkiria) from a site located 400 m away from the forest belt, the yield was 1.36 t/ha, at 200 m – 1.57 t/ha, from a site located directly near the forest belt – 1.7 t/ha.
Buckwheat serves as a predecessor for cereals and leguminous crops.
Because of its weak root system and high nutrient requirements, buckwheat responds well to fertilizer application. To form 1 ton of grain and the corresponding amount of straw it consumes 44 kg of nitrogen, 25 kg of P2O5 and 75 kg of K2O.
Before flowering buckwheat plants absorb up to 61% of nitrogen, 62% of potassium and 40% of phosphorus of the total requirement.
Of phosphorus fertilizers, as established by D.N. Pryanishnikov, buckwheat is able to absorb the phosphorus of phosphate meal, which is applied in the main fertilizer at a rate of 90-100 kg P2O5 per 1 ha.
When sowing, granulated superphosphate at a rate of 10-20 kg P2O5 per hectare is applied at the same time. In Udmurtia (sovkhoz “Pravda”) increase in buckwheat yield from row application of phosphorus was on average 0.34 t/ha for two years.
Of potassium fertilizers sulfate potash or ash at a rate of K40-45 are effective. Higher doses of potassium chloride fertilizers lead to leaf spotting and may lead to lower yields in dry years.
On chernozem, buckwheat responds well to phosphate fertilizers. Adding nitrogen and potassium to phosphate fertilizers does not significantly affect the yield. On gray ashy soils the effect of nitrogen and potassium fertilizers has a greater positive effect, by contrast, the role of phosphorus is somewhat reduced. The highest yield on these soils, as well as on sod-podzolic soils, was obtained with the application of total mineral fertilizer.
Table. Effect of fertilizers on buckwheat yields on different soils (Nosovskaya selection and experimental station)
In many studies, increased nectar production by flowers from the application of phosphorus-potassium fertilizers, better visitation by bees and an increase of inflorescence oviposity were noted.
On sandy loam soils, the highest yields are achieved with the combined application of total mineral and organic fertilizers. Buckwheat is also responsive to the after-effects of fertilizer.
Buckwheat has an uneven and extended period of nutrient consumption, so it is important to distribute fertilizers effectively in order to increase the productivity of buckwheat. According to the Scientific Research Institute of Agriculture (Ukraine, experimental farm “Chabany”) application of N48P45K45 under plowing increased yield from 1.59 to 1.92 t/ha, whereas the application of P30K30 under plowing, N15P15K15 in top dressing in the phase of budding and N30 in the phase of mass flowering – to 2.11 t/ha. The same research institute also proved the efficiency of foliar feeding of buckwheat. Threefold spraying with P15K10 solution during the phase of grain formation increased the yield compared to threefold spraying with water from 0.99 to 1.28 t/ha, while the crude protein content in grain increased from 14.0 to 15.2%.
Nitrogen fertilizers can also be applied during inter-row cultivation of wide-row crops at a dose of N10-15. When sowing buckwheat after well fertilized preceding crops fertilization can be not carried out.
To avoid leaf scorch when foliar feeding, it is carried out in the afternoon after 16-17 hours, using solutions with low concentrations.
Excessive nitrogen in years with sufficient moisture can lead to the formation of a strong aboveground mass and lodging of crops. To avoid this (so that buckwheat does not “grow fat”), it is better to apply organic fertilizers under the preceding crop. Phosphorus-potassium fertilizers are applied before the autumn plowing, nitrogen fertilizers are applied in spring for the pre-sowing cultivation at the rate of N35-40.
Buckwheat is little sensitive to soil acidity, but soils with high acidity need liming. According to the Novozybkovo experimental station of the All-Russian Institute of Fertilizers and Agro-soil Science, the buckwheat yield without lime was 0.89 t/ha, with the addition – 1.34 t/ha.
On light soils we apply magnesium in the form of dolomite flour.
Buckwheat is responsive to microfertilizers in the absence of appropriate elements in the soil. In the experiments of the Novozybkovo experimental station of the All-Russian Institute of Fertilizers and Agrosoil Science the treatment of buckwheat seeds with boric fertilizers contributed to an increase in yield by 0.12-0.7 t/ha. According to V. I. Ulmanis’ (Latvia) experiments, application of copper, zinc and boron fertilizers increases the yield by 13-15%.
Magnesium borate is applied before cultivation, and superphosphate enriched with boron – in the rows during sowing.
Soil cultivation for buckwheat includes early and deep autumn plowing. Stubble discing is carried out beforehand. After row crops on fields clean of weeds, discing may not be carried out, otherwise do the treatment with heavy disc harrows to a depth of 12 cm.
In arid areas, snow and melt water retention is carried out in winter.
In the spring, carry out an early moisture closure with heavy harrows БЗТС-1,0 in two trails with an interval of at least 3 hours, 2-3 cultivation with harrowing, as due to the late sowing there is an opportunity to conduct additional treatment against weeds and better prepare the soil. Heavy or highly compacted soils are cultivated with non-moldboard tools instead of the first cultivation.
The first cultivation is carried out during sowing of early spring crops at the depth of 10-12 cm, the second – 8-12 days later at 6-8 cm, the third – on the day of sowing at the depth of seeding. Only two cultivations are made on light soils. Cultivators such as КСП-4Г, КШП-8, КШУ-12 are used. Before sowing – for more uniform loosening along the depth – УСМК-5,4Б. Cultivators are combined with tooth or sowing harrows with plume harrows, and on light soils – with rollers.
When there is a risk of erosion development, appropriate anti-erosion tillage is carried out.
The last cultivation with harrowing is carried out 1-2 days before sowing to a depth of 5-6 cm.
Preparation of seeds
Buckwheat seeds vary greatly in size and weight due to the extended period of their formation. For this reason, cleaning, sorting and selection of large heavy seeds is a condition for high yields. To sort large, heavy seed fractions, sorting tables, such as ПСС-2-5, or immersion in water or in a 10-15% solution of ammonium nitrate or table salt are used. After immersion, seeds are washed with water and dried.
The mechanical method of sorting is preferable. However, if buckwheat seeds are clogged with wild radish seeds and other weeds, it is possible to separate them completely only in a salt solution.
According to the experiments of the Orlov agricultural experimental station, sowing with light small seeds gave buckwheat yield 1.23 t/ha, with small heavy seeds 1.52 t/ha, with light large seeds 1.6 t/ha, and with large heavy seeds 1.91 t/ha.
To increase germination energy and field germination of seeds, sun heating or air-heat treatment with active ventilation are used.
To control fungal diseases, such as gray rot, false powdery mildew and others, which may cause the death of up to 20-30% of plants, the seeds are treated with 80% ТМТД at a rate of 200 g of the preparation per 100 kg of seeds.
Timing of seeding
Weather conditions affect buckwheat yields more than other field crops. Early sowing can cause damage to seedlings by spring frosts, and late sowing can be negatively affected by heat and lack of moisture.
Sowing begins when the soil at a depth of 10 cm warms to 12-15 °C and there is no risk of frosts. The timing of sowing in all areas of Russia must take into account the need to create favorable conditions in the phases of flowering and fruit formation, that is, the temperature is not more than 25 °C and adequate moisture. To do this, in some cases, sowing is carried out in two terms with an interval of 10-15 days.
The more late-ripening varieties, the more yield decreases with delayed sowing, because it is in unfavorable conditions of temperature and moisture in the second half of the growing season, and tolerates them worse with a stronger development of the above-ground mass. Rapid-ripening varieties suffer more from low temperatures at the beginning of development, they are sown 10-15 days later than late-ripening ones.
Optimum sowing dates of buckwheat:
Non-Black Earth, Central Black Earth zone, Far East – the third decade of May – beginning of June;
south of the Black Earth zone, Volga region – second half of May;
south of the forest-steppe – first decade of May;
north of the steppe – last decade of April.
In the south of Russia, buckwheat is also sown in the stubble after the main crop is harvested. Short-ripening varieties are the best for this purpose.
Sowing methods and depth
The main ways of buckwheat sowing are wide-row, row and narrow-row (7.5 cm). Wide-row method with a row spacing of 45 cm is used in weedy fields, in areas with high soil fertility, for late- and mid-ripening varieties, as well as in case of moisture deficit.
Experiments conducted in the Leninsky district of the Moscow region (collective farm “Bolshevik”) showed that the highest yield is achieved with a row spacing of 45 cm and seeding rate of 45 kg/ha.
In the steppe arid areas, the width of the row spacing is increased to 60 cm.
For seeding also used double row or strip methods with a distance in the bands of 10-15 cm, between the bands – 45 cm.
The row method (13-15 cm) is used in the cultivation of weakly branched early maturing varieties on poor not swamping soils, as well as in the absence of weeds. In this case, the row method is more economically advantageous, as it does not require inter-row tillage.
According to the long-term data of 200 state variety plots, in 60% of cases continuous row crops of buckwheat produced higher yield than width-row ones. Only in 15-20% of cases the wide-row method had an advantage.
With the wide-row method the direction of sowing rows in relation to the sides of light is important. As a result of improved light conditions and other environmental conditions, sowing from north to south creates good conditions for the development of strong plants and less shading of each other.
Table. Effect of row directions on buckwheat yields against fertilizers (former Kamenno-Stepskaya experimental station)
|From west to east|
|From north to south|
Depending on soil and climatic conditions, varietal characteristics and agrotechnics, the seeding rate for the wide-row method varies from 1.5 to 3 million/ha of germinated seeds or 45-60 kg/ha.
With the row method from 2.5 to 5 million/ha or 80-100 kg/ha.
On weedy fields and in the strip method the seeding rate is increased by 15-20%.
The sowing depth of buckwheat depends on the seed size, sowing time and soil properties. On wet heavy soils, the seeds are sown to 4-5 cm, on light, more drying soils – to 6-8 cm.
Shallow sowing leads to thinning of seedlings, poor development of adventitious roots, and reduced grain formation.
At the Chernigiv Agricultural Experimental Station, buckwheat embedded at a depth of 3-4 cm gave a yield of 1.53 t/ha, at 6-7 cm – 1.68 t/ha.
In Belarus, joint sowing of buckwheat and winter rye is practiced, which can increase the yield by 1.5-2 times. In autumn, winter rye is sown in strips, the width of which is set by the width of the harvester’s header. In spring, between strips of rye planted buckwheat in strips width of 7.2 or 10.8 m, ie 2-3 passes grain seeder. Strips are located on the rye-wheat field perpendicular to the direction of prevailing winds.
In Voronezh Agrarian University good results were obtained by joint sowing of buckwheat and millet.
Crop care begins with rolling the field with knurled or circular rollers. At formation of crust and weeds germination before and after sprouting, loosening with light harrows ЗБП-0,6А, ЗОР-0,4, middle harrows БЗСС-1,0 or rotary hoes is done. Yield increase from this method is up to 0.3 t/ha.
On wide-row crops when sprouts perform inter-row tillage to a depth of 4-6 cm. As weeds grow and soil compaction before flowering, crops are loosened 1-2 times УСМК-5,4А and conduct weed control in rows. The first inter-row processing is carried out in the phase of the first true leaf at a depth of 5-6 cm with a protective zone of 8-10 cm, the second – in the phase of the budding of 6-8 cm in dry weather or 10-12 cm – in wet.
To improve pollination, beehives are placed on crops 2-3 days before flowering, at a rate of 2-3 beehives per 1 hectare. Bee efficiency depends on the amount of nectar released by buckwheat flowers, and the remoteness of the apiary from the crops. According to the data of the Ukrainian Experimental Station on Beekeeping, the yield of buckwheat near the apiary was 1.8 t/ha, at a distance of 0.5 km – 1.28 t/ha, at 1 km – 0.96 t/ha.
When applying herbicides and insecticides on buckwheat crops to control weeds and pests, special attention is paid to environmental safety requirements, since buckwheat is a honey-bearing crop.
Post-mowing and stubble crops of buckwheat
Post-mowing and stubble crops serve as a quick, affordable and economical reserve for increasing the gross harvest of buckwheat in the Northern Caucasus, Central Black Earth zone, as well as in Ukraine, south-east of Kazakhstan and Kyrgyzstan. Stubble buckwheat crops in these regions allow to get 1.2-1.6 tons of grain per 1 hectare.
After mowing, buckwheat is sown after harvesting winter cereals and spring crops for green fodder and silage, and after harvesting them for grain. On irrigated lands buckwheat may also be cultivated after these crops to a stubby crop or after mowing in the meliorative field of rice crop rotation.
In this case the soil is prepared and buckwheat is sown immediately after the main crop is harvested. Late sowing leads to a sharp decrease in yield. On irrigated lands before this make pre-sowing irrigation with the norm of 600-800 m3/ha of water. During the growing season, according to the Novocherkassk Melioration Engineering Institute, in the active soil layer (0-60 cm) moisture content of 80% of the lowest moisture capacity must be maintained. Full mineral fertilizer (N45P45K45) is applied. Crops after mowing are sown in wide rows, on clean soils – in a continuous row. The rate and depth of sowing increases (up to 100-110 kg/ha).
Ripening of buckwheat fruits lasts 20-30 days and they easily fall off, and the ripening period is shorter in dry weather and longer in rainy weather. So the harvesting is carried out in two-phase manner, which begins when 65-85% of fruits are rotted. When all fruits are brown, the loss reaches 0.45 t/ha, so mowing is carried out in a short period of 3-4 days. Plants are mowed by reapers, for example, ЖВН-6. Mowing is best done in the morning or evening hours to reduce losses from shattering. After 5-6 days of drying (in dry weather 2-4 days), when grain reaches a moisture content of 13-16%, combine threshers with pickers. To avoid the destruction of the grain, the frequency of rotation of the drum is reduced to 500-600 revolutions per minute, the decks are lowered. For threshing rolls with normal humidity, it is better to use a single-drum combine, with high humidity – two-drum. Simultaneously with threshing, cleaning and drying of grain to a moisture content of 14-15% is carried out.
Two-phase harvesting contributes to an increase in the harvest by 0.2 t/ha and more (experience of collective farms named after Lenin and “Krasny Pakhar”, Nizhny Novgorod region).
Single-phase harvesting method is used for harvesting low-growing and uniformly ripening early-ripening varieties. It is also used for rainy weather and thinned crops.
Under irrigation, buckwheat increases its yield significantly, but it does not tolerate the soil crust produced by irrigation. The first irrigation is done before sowing, then – at the beginning of branching phase, at flowering and fruit formation. Water consumption is 500 m3/ha, irrigation method – furrow irrigation by infiltration or sprinkling.
Sowing under irrigation conditions is early wide-row. According to the experiments of K.A. Savitsky and I.P. Reznichenko in the farm “Gora” Kiev region of Ukraine on average over 2 years with buckwheat sowing on May 5 in irrigation conditions, the yield increased by 1.1 t/ha, May 20 – by 0.61 t/ha. With the row method, the increase from irrigation was 0.31 t/ha, with wide-row – 0.85 t/ha.
Progressive cultivation technology
Application of advanced technology in the Novoukrainian area of Kirovograd region of Ukraine (collective farm “Russia”) increased buckwheat yield from 1.25 t/ha (1971-1975) to 2.41 (1982), sown area – from 178 ha (1971-1975) to 389 ha (1982). The share of buckwheat sown area in the structure of cereals was 12%. Labour inputs per 1 ha amounted to 15.4 man-hours (1982).
The technology used was developed by Kirovograd zonal agricultural station.
Forecrop – cereals, corn, sugar beet.
Tillage – stubble discing to a depth of 5-7 cm, under-winter plowing to a depth of 25-27 cm. In spring, the soil is harrowed and 2-3 cultivated with 0.25 t/ha of ammonium nitrate added to the last one.
Seeding is carried out by wide-row beet seed drill ССТ-12А with the introduction of 50 kg/ha of superphosphate in rows. The depth of seeding – 6 cm, the rate of seeding – 70 kg / ha. Shatilovskaya 5 variety.
Care for crops includes rolling after sowing, two inter-row treatments at a depth of 3-6 cm, bee pollination.
Harvesting is two-phase, mowing when 70-75% of grains are browned, threshing is done in 3-5 days.
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.