Forage beans (Vicia faba), also vegetable beans, are a grain legume agricultural fodder and food crop.
Due to some confusion about trivial crop names on this page, the term “bean” or “forage bean” refers to the species Vicia faba. Another species, also called “bean” is described on the page “Beans” (Phaseolus vulgaris).
Contents
- Economic importance
- History of the crop
- Cultivation areas
- Yields
- Chemical composition and nutritional value
- Botanical description
- Physiology
- Biological features
- Vegetation
- Crop rotation
- Fertilizer system
- Irrigation
- Tillage
- Sowing
- Crop care
- Weed control
- Features of cultivation of winter and spring forms
- Harvesting
- Diseases
- Pests
- Seed production
- Breeding
- Sources
Economic importance
Fodder beans are used in agriculture for fodder purposes. They are distinguished by their feed value. Recent studies have shown that beans can be used to replace soybean meal in pig diets, as well as in beef production. Despite the presence of tannin in the seed coat of beans, experiments have shown that feeding pigs a relatively high proportion of beans during the stages from growing to finishing pork production has no harmful effects (Houdijk et al., 2013), but because the amino acid profile of beans lacks sulfur-containing amino acids, some balance must be achieved by using synthetic substances.
Seeds are used for compound feed production, green matter is used to make silage usually with corn. Flour and steamed beans are used for fodder purposes. In Scandinavian and Scottish aquaculture, there is a growing demand for beans. They are husked and used to make compound feed pellets for salmon farming. The feed must be adjusted with synthetic amino acids and additional fish meal, but the beans are well suited to retain the pellets after they are submerged in water, and the specific gravity allows the pellets to sink slowly, providing the maximum opportunity to feed the fish. The husks are then pelleted and sold as a source of fiber for the feed industry.
Coarse-seeded beans in their green ripeness state can be used for food purposes and canning. Whole beans and immature grains in the lactic or waxy ripeness stage are used for vegetable beans.
Beans are also a staple food in the Middle East and East Africa. Egypt and Sudan grow a large share of beans, but the current consumption of 500,000 tons per year of beans cannot be met by local production. This market requires large-seeded beans with pale skins that must be spotless and with a thin, intact seed coat. High quality beans from Britain, France, and Australia are exported to the Middle East each year. The beans are soaked and boiled whole with spices as “breakfast beans” (foul mesdames) or ground to make falafel. They are an ideal source of slow release energy, especially during Ramadan when food can only be eaten during the dark hours of the day.
Sometimes bean flour is mixed with wheat flour to increase the nutritional value.
Bean straw exceeds oat straw in protein (14 percent) and fat content but is coarser, so it is ground before being fed. It is also used as an organic fertilizer.
Green mass, mowed during flowering, can be used for green fodder or making silage, haylage, hay. The chemical composition: moisture – 76%, protein – 3.6%, fat – 0.8%, fiber – 7.0%, minerals – 1.4% of the crude weight. 1 kg of green fodder corresponds to 0.16 fodder units and 24 g of protein.
Honey-bearing plant. Gathering of honey reaches 20-25 kg per 1 ha.
At present fodder beans are used as a green fertilizer in stand-alone or mixed crops. In humid subtropical conditions, they are grown for this purpose in winter; they are sown in autumn after harvesting the main crop and plowed in spring.
On the roots of beans in the upper layer of soil (0-10 cm) and at a radius of 10 cm from the main root, in the places where nitrogen-fixing bacteria penetrate them, spherical nodules 2-4 mm in diameter are formed. Due to powerfully developed root system and its symbiosis with nodule bacteria, beans can provide 70-80% of nitrogen. Together with bean stubble, up to 220 kg/ha of nitrogen remains in the soil.
The advantage of beans over other grain legumes is their non-legality and the possibility to grow them as a row crop. They are distinguished by their high nitrogen-fixing ability: they accumulate 70-250 kg/ha of nitrogen during the growing season.
Because of their versatility in field crop rotations, beans are popular because they are a useful non-grain crop, reduce the burden on seasonal jobs and have a household market for both human and livestock consumption.
As with peas, the supply of beans depends on demand and the price depends on quantity and quality. The market for human consumption is influenced by strong competition from Great Britain, France, and Australia, and the weather in different production areas can have a direct unfavorable or favorable effect on the quantity available.
History of the crop
The garden bean comes from Southwest Asia and North Africa. According to P.M. Zhukovsky, the forage bean comes from the Mediterranean, so it is demanding of moisture and heat during the ripening period. From North Africa comes the large-seeded form, and from Asia the small-seeded and small-seeded form.
Forage beans are an ancient agricultural crop. V. faba is known to have grown in the Middle East and the Mediterranean and has been grown as a food crop since 6000 B.C. From the Middle East, the crop may have spread to Central Europe and Russia via Anatolia, the Danube Valley and the Caucasus, and from the Mediterranean coast to Egypt and the Arabian coast. It spread through Abyssinia and Mesopotamia to India and China, probably during the first millennium AD.
Ancient Egyptians, Greeks, and Romans often mentioned beans, and one of the oldest archaeological remains of the seed was found at Nazareth and dates back to 6500-6000 B.C. The first remnants of the culture in Great Britain were found in the excavation of an Iron Age site at Glastonbury.
2,000 BC the garden bean was cultivated in southern Europe (Ancient Greece and Rome) and northern Africa (Ancient Egypt) for food and forage purposes.
Forage beans are still widely cultivated in the Mediterranean region, despite the fact that some people are allergic to the crop, known as favism (Zinkham et al., 1958). The condition is now known as an inherited deficiency in some Mediterranean residents who lack the enzyme glucose-6-phosphate dehydrogenase in their red blood cells. Eating raw beans or inhaling pollen causes sudden destruction of red blood cells or acute hemolytic anemia. There is much speculation about the connection between Favism and the death of Pythagoras in ancient Greece. Stories are known about how Pythagoras did not try to hide from his enemies by entering a field of beans, but the condition of favism is so rare that it seems unlikely that this was the reason for his refusal to approach the crops (Simoons, 1996). Later, in the first century AD, the oldest surviving cookbook of the Roman Apicius gives nine recipes for cooking beans, with both mature (dried field) and immature (broad) beans used (Edwards, 1985).
Notes on cultivation also survive from the classical period, and Pliny recorded that “when the bean blooms, it needs water, but when it has bloomed, it needs little water” (Bostock, 1828). During the Middle Ages, interest in beans was probably stimulated by reports of their medicinal properties. In addition to their use for treating “old pains, bruises and tendon wounds, sciatica and gout,” Culpepper describes the use of beans for “cleansing the face of blemishes and wrinkles” (Sibley, 1802). Such comments may have contributed to increased production. However, the use of field bean seeds as a source of high protein and carbohydrate content meant that they were used for both human and animal nutrition.
It is essentially an Old World crop, but it was introduced to America in the 16th century, and by the late 20th century it had made its way to Australia as a commercial crop.
In the late 19th century, beans were widely grown in Northern Europe, and in 1873 about 224,000 hectares were grown in Great Britain alone (mostly for horse feed), equivalent to the area of wheat. One of the main reasons for the decline was the increased availability of cheaper protein from abroad. During World Wars I and II there was a slight rebound due to difficulties with imports. There was also an increase in livestock production, and most of the beans were used as animal feed. With the development of the internal combustion engine and the introduction of machines on farms, the need for domestic beans for farm horses declined, and since the end of World War II imports of soybeans as a cheap protein feed for livestock have increased dramatically. However, their value as a profitable low-cost soil-improving crop in a major grain rotation, yielding products that can be used as an alternative to imported soybean meal, means that interest in the crop has increased, and so field beans are being revived, particularly in Northern Europe and Australasia.
In modern Russia, the crop has been cultivated since the 6th-8th centuries.
Cultivation areas
Beans are one of the most important legume crops in the world, with global production exceeding 4 million tons, although production in developing countries is still insufficient for human consumption.
Forage beans are now widely grown in Europe, in parts of southeastern Australia, in the Middle East (including Egypt) and in small quantities in Canada. Very large areas are available in China, mostly for domestic use. It is considered a temperate crop, not adapted to the tropics except at high altitudes: it was introduced by the Spanish into the Andes.
At present the largest areas of horse bean production are in China, with about 1 million hectares, Great Britain with about 100,000 hectares and production of 400,000 tons a year, followed by France with 80,000 hectares, giving about 300,000 tons, while Australia produces about 150,000 hectares and 300,000 tons.
In the USSR the area of crops was about 20 thousand hectares. In the world – about 2-5 million hectares or 1.6% of the area occupied by leguminous crops.
In Russia, fodder beans are cultivated mainly in areas with sufficient moisture and a long growing season, primarily in the Non-Black Soil Zone, as well as in Dagestan and Western Siberia. The northern border of cultivation runs along 65°N. In the former Soviet Union, they are grown in Belarus, the Baltic states, the right bank of Ukraine, and in Transcaucasia. In the world the main sowings are concentrated in the Mediterranean countries, Western Europe, Egypt and Brazil. Its gross seed yield is 3.4 mln. tons or 1.5% of grain legume seed yield. The average yield is 1.5 t/ha.
At present there are no statistics on this crop in Russia. It is supposed to be planted on an area of 10 thousand ha.
Forage beans are of interest because they can be cultivated on the heavy clay and podzolic soils of northwestern Russia.
Yields
Forage beans are a high-yielding crop. During the Soviet period, a maximum yield of 6.29 t/ha was obtained in Estonia. In areas with favorable conditions for their cultivation, forage bean yields are higher than those of other leguminous crops. For comparison, according to the Research Institute of Agriculture and Animal Husbandry (Ukraine) the yield under the same conditions:
fodder bean seed was 2.83 t/ha, straw 3.12 t/ha, which corresponds to 36.5 fodder units and 810 kg/ha of protein;
pea seeds – 1.71 t/ha, straw 3.04 t/ha, corresponding to 20.2 fodder units and 300 kg/ha of protein;
beans seeds – 1.44 t/ha, straw 2.04 t/ha, which corresponds to 16.3 fodder units and 190 kg/ha of protein;
fodder lupine seeds – 0.85 t/ha, straw 2.95 t/ha, which corresponds to 11.7 fodder units and 270 kg/ha of protein.
The ratio of straw to seeds in beans is about 1:1, while in other legumes it varies from 1.5 to 3.5:1, which is an indicator of a high-yielding crop of the intensive type.
Yield of green mass of fodder beans is 25-50 t/ha, dry mass – 10 t/ha. But it strongly depends on the amount of precipitation during the growing season.
Seed yield under favorable conditions is 2.1-5 t/ha.
Chemical composition and nutritional value
Typical nutritional value of vegetable chillies (broadleaf) beans (data from the British Growers Association and U.S. Department of Agriculture Standard Reference SR27), per 100 g of product:
- caloric value – 461 kJ;
- protein – 5.6 g;
- total carbohydrates – 11.7 g (1.8 g as sugars);
- dietary fiber – 4.2 g;
- sodium – 50 mg;
- vitamin C – 33 mg.
Nutritional value of dried vegetable beans (USDA Standard Reference SR21 data), per 100 g of product in boiled form:
- caloric value – 461 kJ;
- protein – 7,6 g;
- total carbohydrates – 19.7 g (1.8 g as sugars);
- dietary fiber – 5,4 g;
- sodium – 5,0 mg;
- iron – 1.5 mg;
- folate – 107 mg.
Nutritional value of feeds
As ingredients or components for animal and fish feeds, forage beans are well-known sources of protein and energy, although low in some sulfur amino acids. Forage beans have a total protein content between soybean meal and grains. As with all raw materials, total crude protein (calculated as nitrogen x 6.25) varies between crops, growing conditions, and year; however, on average, protein values remain standard, and feed manufacturers use established values for forage beans of about 25%. In a study of commonly grown bean varieties (spring or winter), very little variation in protein was found between pea varieties (Bastianelli et al., 1995).
1 kg of seeds corresponds to 1.29 fodder units and contains 250 g of digestible protein.
Nutritive value of fodder beans:
- dry matter – 86%;
- oil – 1.5%;
- starch – 37.0%;
- cellulose – 8.0%;
- minerals – 3.5%;
- protein – 25.0%;
- amino acids:
- lysine, 1.56%;
- methionine – 0.18%;
- cysteine – 0.48%;
- threonine – 0.85%;
- thiamine – 0,21%;
- valine – 1.11%.
For comparison, the feed value of soybeans (Hy-Pro) is given:
- dry matter, 86%;
- oil – 1.9%;
- cellulose, 6.0%;
- minerals, 6.4%;
- protein – 54.3%;
- amino acids:
- lysine, 2.92%;
- methionine – 0.65%;
- cysteine – 1.35%;
- threonine – 1.86%;
- thiamine – 0,65%;
- valine – 2.27%.
The composition of amino acids in beans depends on the total protein content and the ratio of various proteins. Lysine levels are intermediate between soybean meal and grains, which is essential nutrition for non-ruminants, but beans do not contain enough of the amino acids sulfur or tryptophan.
Starch is the most abundant component of beans, about 500 g/kg, and is a valuable source of energy for livestock. The average oil content is low (less than 2%). The composition of this oil is similar to that of grain crops, mainly triglycerides, polyunsaturated in nature with a predominance of linoleic acid.
In forage beans, most varieties contain tannins, but there is insufficient evidence to suggest that their content is high enough to affect pig growth (Houdijk et al., 2013).
Many studies have examined the value of beans as a protein source for livestock, and it is recognized that forage beans can be used in nutritionally balanced diets for many ruminants and non-ruminants and can completely replace soybean meal without detrimental effects on livestock performance. In addition, the increasing use of feed beans in aquaculture for salmon farming in Norway and Scotland will gradually replace the need for fishmeal in diets.
Botanical description
Forage bean (Vicia faba L. or Faba vulgaris Moensh vicia faba L.) is an annual leguminous herbaceous plant.
The root system is taprooted, spindle-shaped, well developed, and penetrates into the soil to a depth of 100-150 cm. Large active nodules are formed on the roots.
The stem is tetrahedral, strong, thick, straight, not lodging, hollow inside, branched at the base, foliage from 30 to 200 leaves. Stem length varies greatly among cultivars from 30 cm to 2 m and is related to the distance between internodes, since very short-stemmed cultivars have short internodes. Branching is weak at the base; it is stronger with thin crops.
Leaves elliptic, non-pair or pair-pinnate, glabrous, bluish-green, fleshy, smooth-edged, with large leafstalks and a point on the tip. The lower part of the stem is unipartite, the middle part is bipartite, the upper part is 3- and 4-partite.
Flowers are arranged on short axillary pedicels all over the stem, gathered in short brushes. There are from 2 to 6 (12) flowers on one brush. Flowers are white, less frequently pinkish with a black spot on wings, large, 2.5-3.5 cm long. Depending on the variety, the flowers may be entirely white, but both sepals and petals may possess anthocyanin pigment of purple to pink intensity, and in most cases have black or purplish melanin spots on the winged petals, but there are at least two genes which pass on the absence of the winged spot and are pleitropically related to the absence of color on the main petal, the stem and the absence of tannin in the seed coat.
The structure of the flowers is adapted to insect pollinators, although in some cases self-pollination occurs. They have a characteristic papillate, zygomorphic shape and longer corolla tubes than in most other legumes. The sepals are united into one five-toothed calyx. The irregularly shaped corolla consists of five petals, the standard two wings and two lower petals united along the outer edge into a keel. The flower has ten stamens, of which the upper one is physically free. The stamens of the other nine are united in a sheath that surrounds the ovary. The single ovary has two to nine testes (sometimes more) located along the inner, upper suture. The stigma is located almost at right angles to the ovary.
The fruit is a large pod 3-40 cm long, pubescent, straight, fleshy. The average number of seeds in the pod varies from two or less to eight, and in some varieties there may be more. This is usually a stable trait, although there may be fewer seeds on the upper nodes, and those pods that are formed at the upper end of the stem may contain shriveled ovaries. The number of seeds may be greater in large-seeded varieties. The inside of the pod is pubescent. If a parchment layer is present in the pods, they are smooth with a weakly meshed pattern; if they ripen, they crack; if there is no parchment layer, the beans are wrinkled. The young bean is green, while the mature bean is dark brown or black.
Seeds vary in shape, color, and size. The shape of the seeds is rounded, kidney-shaped, flat, oval, or rolled. The color of an immature seed is usually cream or gray-blue or green, though the color of a mature seed is most often gray-beige, less often white, yellow, green, purple, dark purple, brown, black; in most cases the color darkens with age, especially after harvesting. Weight of 1,000 seeds is 180 to 2,500 g, usually 280 to 530 g. Environmental conditions can affect seed weight, with moisture being the most important factor. Dryer growing conditions can reduce seed weight by 25%. Seeds vary in coarseness (0.7-3 cm in length).
Seeds of forage beans with not entirely white flowers contain anthocyanins, which darken with age. Beans with white flowers usually produce mature seeds of a more gray color. Hilum color can be black or white and depends on the variety. Preferred varieties of horse beans grown for human consumption in dried form usually yield white hilum.
Varieties
Although there are other members of the Vicia genus that are grown as cultivated plants, such as Vicia sativa, V. faba is genetically distant and no successful interspecific crosses have been made. This limits the variability available for breeding V. faba, and varietal development is further complicated by frequent cross-pollination between different varieties, resulting in a wide range of genetic characteristics within the same population.
Depending on the size of the seeds are subdivided into:
- small-seeded (v. minor Beok) – weight of 1000 seeds 200-450 g, seeds rolled, plants are tall, medium and late maturity from 105 to 140 days, the yield is high, used for forage purposes;
- medium-seeded (v. eguina Pers.) – weight of 1000 seeds 500-700 g, seeds are flat-oval, medium and late maturing from 110 to 140 days, plant height from 70 to 200 cm, the fruits are set high, high yield, used for forage purposes;
- large-seeded varieties (v. major Harz.) have 1000 seeds weighing 800-2500 g; seeds are flat, early maturing (95 to 105 days), plant height 50 to 100 cm; bean attachment is low, thus mechanical harvesting is difficult; cultivated mainly as a vegetable crop for large beans with thick, fleshy pods. These beans are also called food beans, vegetable beans, Russian beans, horse beans.
Internationally, the term “faba bean” is usually used to avoid confusion with other bean species, some of which are also described as field or common beans. The latter are referred to a group of bean species (Phaseolus). The term “broad bean” refers to those varieties of V. faba that are harvested before the seeds mature and dry and are used as a vegetable.
Faba bean is also classified into winter and spring forms. Winter forms are usually more suitable for cold and heavy soils that are difficult to cultivate in early spring. There is more opportunity to plant winter bean after a dry summer in favorable soil conditions, allowing it to take root as young plants before winter arrives. The varieties tend to be highly viable, allowing rapid germination and emergence of seedlings in a variety of conditions. Plants have ample opportunity to form multiple shoots, which help keep plant height at an acceptable level while compensating for the smaller number of plants.
Spring bean varieties have a wider variety of varietal characteristics, some are relatively shorter, mature a little earlier, and are easier to harvest mechanically. This has allowed the development of spring bean cultivation in more northern temperate areas, as well as increased production opportunities in several European and Australian countries. However, spring bean yields are negatively affected by water stress and drought, especially during the flowering and reproductive growth phases.
Agriculturally, the development of fall- and spring-seeded varieties of horse beans has led to considerable differences in varieties, growing practices, pest and disease characteristics, timing and ease of harvesting, so in many respects, horse beans can be considered a different crop. This increases the value of the species to farming systems in many temperate areas and allows selection of the type of crop best suited to specific growing conditions.
Spring and winter forms have different varietal characteristics, including white-flowered and colored varieties. White-flowered varieties are low in tannin, which is perceived as an anti-nutritional factor in some livestock diets. Colored varieties are easier to grow, and white-flowered beans are much more difficult to produce because of their ability to cross-pollinate.
Physiology
Germination
The germination process of bean seeds is very similar to that of pea seeds. In hypogeal germination, the germ axis lengthens, then ruptures the testis, and the apical part of the germ develops as a plumula appearing above the soil surface, while the seed remains underground.
Vegetative development
The nature of stem growth depends on the variety and cultivation technology, but the habit of the plant to branch becomes stronger the earlier the date of sowing. For example, winter varieties sown in the fall have a higher number of stem branches than varieties sown in the spring. As plant density increases, the number of stem branches per plant decreases. Bean branching is similar to that of most legumes in that they have a centrifugally located series of buds that establish on each leaf axis (Dormer, 1954). Basal branching arises from these buds in the lower part of the stem (Bond and Poulsen, 1983).
Depending on the cultivar and growing conditions, stem height varies from 120 cm to 200 cm, but environmental conditions such as drought or excess moisture can dramatically affect crop height. In general, stem strength is good and allows the plant to remain upright into adulthood.
The first two leaves at the base of the stem remain dormant, with only small shoots visible. The first leaflet usually appears at the third node, and the first few leaves have only two leaflets. The leaves usually consist of two pairs of ovate leaflets, although the number of leaflet pairs increases after the flower buds have set. There are toothed stems, but no tendrils.
Stem growth is affected by temperature as well as soil type, moisture availability, and incident light. During periods of low light or high plant density, stem length increases as the internodes lengthen. Environmental conditions, including nutrient availability and water stress, also affect leaf growth.
Root development
Root growth of V. faba begins immediately after the seed begins the germination process. Within a week of germination, a well-developed root cap develops, and 2-3 days later, a primary root emerges from the seed and lateral roots begin to set. The primary root continues to grow downward, and the lateral roots spread from the main tap root. Nodulation occurs when soil-borne Rhizobium bacteria infiltrate the root hairs, and nodules develop at the top of the tap root, where they become abundant. The nodules tend to be smaller on the lateral roots, but as the plant matures, these small nodules take over nitrogen fixation from the older, larger nodules on the tap root.
Flower development
Flowering is early, beginning a month after sprouting, lasting until the bottom beans are full, and in wet summers until autumn frosts.
Petals are united and mobile, and pollination occurs when an insect pushes down on the wing and keel of a petal, releasing stigma and pollen. In doing so, the pollen is transferred to the hairs of an incoming insect, which can then cross-pollinate other flowers on the same or neighboring plants.
The flowers emit a strong scent that is attractive to pollinators and other insects (Somerville, 2002). Bees play a crucial role in bee pollination. The importance of bees in cross-pollination and improving production is well known (Poulsen, 1975; Svendsen and Brodsgaard, 1997). Bumblebees (Bombus spp.) are the most common pollinators of V. faba flowers in temperate regions. In most countries, honeybees (Apis mellifera) collect pollen from V. faba, and in some regions hives are often taken to crops during flowering (Bond et al., 1985).
The location of the first flowers and first pods are not necessarily the same, as flower drop may occur immediately after the petal has fallen, and the number of flowers on the flower stalk and the number of pedicels on the plant almost always exceeds the number of pods developing to maturity. About 10% of the flowers are thought to survive and form mature pods. Environmental conditions have a major impact on this characteristic of horsebeans, especially under low light or shade conditions in dense plant populations, as the stem elongates and produces more flowers on the upper part of the stem. This can cause the lower flowers (which may have even been fertilized) to fall off without forming pods.
Pod development
As the fertilized ovary develops into a pod, the remaining petals wither and fall off, leaving the pod open. The number of reproductive nodes with pods varies among varieties, but depends more on environmental conditions. Pods are usually formed in groups of two or three at each node, starting at the fourth or fifth leaf node and up to the tenth or even higher nodes. Plant density and number of branches affect the number of pod nodes, as plants with low population densities produce more of them than those growing at high densities, provided that growth is not limited by water availability, nutrient deficiency or biotic stresses.
Most horse bean varieties have dehiscent pods, but they are less likely to wilt before harvesting than peas. Leaf wilting occurs during seed growth with reduced root activity and increases with higher temperatures and water stress.
Biological features
Temperature requirements
Fodder beans have low heat requirements; they are considered one of the most cold-resistant vegetable crops.
Seeds begin to germinate at 3-4 °C, the optimal temperature for the emergence of uniform sprouts is 5-6 °C. According to other data, the optimum temperature is +19 … +20 °C, at which sprouts appear in 7 days (Autko). Sprouts withstand short-term frosts to -4 … -6 °C.
Average temperatures for growth and development are 15-20°C. Overwintering forms can develop at lower temperatures. The optimal temperature for growth is +18 … +19°C; the optimal temperature for flowering and setting beans is +15 … +18°C.
High temperatures above 30°C inhibit growth, especially during flowering. Autumn frosts pose a danger during extended fruit ripening.
Moisture requirements
Fodder beans have higher requirements for moisture, especially in the period from seedlings to full bloom. Transpiration factor is 800.
For seed swelling and germination, 110-120% water of seed weight is required.
Garden bean is poorly tolerant of air and soil drought. During drought, the leaves wither and fall off, resulting in a dramatic decrease in yield. In dry weather, only the lowest beans set and the upper buds fall off.
Excess moisture is also unfavorable: grain yield decreases as the number of fertilized flowers decreases and disease and pest damage increases.
Light requirements
Fodder beans belong to the long day plants.
Soil requirements
They grow well on medium-moistured, moisture-laden loamy and well-moistened loamy-sandy soils with high organic matter content, as well as drained peatlands.
Soil pH is an important factor affecting bean yield, and the optimum pH before sowing is about 6.9-7.3 (other recommendations are 6-7). However, in many arid parts of the world, pH values of 8.5 are often found, and this does not generally have a negative effect on yield, provided sufficient micronutrients are available. Crops grown on acidic soils are less vigorous, paler in color, and less productive than crops grown at the optimal pH range. Reduced vigor causes seeds to become shallower and seed weight per plant to decrease. When the acidity value is less than 6, perform liming.
It does not tolerate soil salinity. Beans can also be grown on light soils, but they must be moist and well fertilized.
Tests on variety plots showed the yield on chernozem soils 1.2 times more than on sod-podzolic soils, and 1.4 times more than on gray forest soils.
Have the ability to assimilate sparingly soluble phosphates.
Sandy, stony and boggy soils are unsuitable.
Vegetation
Vegetation period from seedlings to technical ripeness is 40-55 days, biological – 70-140 days.
Cross-pollination or self-pollination.
Growth and development phases:
- sprouting;
- budding;
- flowering;
- ripening.
Bean seeds are usually planted early in the season in a wide range of soil types. However, like peas and beans, they are sensitive to compacted soil layers. Beans can tolerate somewhat heavier soil types than peas, making them more versatile for cultivation in a variety of conditions. Good drainage is important.
Spring beans are usually planted as early as possible to ensure development of an adequate root system before summer, when moisture deficiency may be an issue. Seeds tolerate prolonged cool conditions well before germination.
Fall varieties, known as winter beans, can be planted in late fall in heavier soils that retain moisture well and are less susceptible to drought so that the root system has time to form before winter arrives. A period of low temperatures during the winter promotes the formation of numerous shoot branches that are compact in early spring until they elongate with rising temperatures. Winter beans are planted at a lower density than spring varieties to allow for an increased number of stems, all of which are productive.
Over-wintering fall-seeded beans make them more susceptible to leaf diseases caused by fungal pathogens such as Botrytis fabae and Ascochyta fabae, but modern varieties are much more resistant to these fungi, which can also be controlled with chemical treatments during the growing season.
Crop rotation
Main article: Leguminous crops of the crop rotation
Crop rotation is important because frequent cultivation of beans in the field can result in the accumulation of soil root infection fungi. Also, populations of the pea gall nematode (Heterodera gottingiana) and broomrape (Orobanche crenata) and others, when introduced, can survive in the soil for a period of time.
It is recommended to place beans after organic fertilizers.
In crop rotations, fodder beans are placed after winter cereals following fertilized fallow or green manure and row crops, as well as after spring wheat and barley.
Vegetable crops are best preceded by row crops: cabbage, beets, potatoes, and corn.
Cultivated for silage (as a separate crop or mixed with corn), it may be grown as a vaporizer crop under winter cereals.
Forage beans in the crop rotation are good precursors for most field and vegetable crops.
Beans should not be placed after legume crops. It is allowed to return beans to their former place in the rotation not earlier than in 4-5 years.
Fertilizer system
Vegetable beans grown for fresh beans or forage beans, respectively dried beans, have limited fertilizer requirements. Beans are less responsive to fertilizer application than many other crops, but some soils may be deficient due to low fertility, soil compaction or acidity (Biddle). At the same time, according to domestic observations, beans respond well to organic and mineral fertilizers on all soils, even chernozems.
As a legume plant, beans provide their nitrogen requirements through nitrogen-fixing rhizobia. Rhizobia are common in agricultural soils, although they may not be present in areas where beans have not previously been grown, in which case rhizobia are often applied as an inoculant, either in the soil before sowing or as a seed.
Mineral nitrogen applications have little effect on yield, and beans have a low efficiency in its use, although some increase in vegetative growth may be obtained. Excess soil nitrogen can inhibit nodule formation.
Phosphate levels in most agricultural soils are relatively high, and there is a very poor response to phosphate when large amounts are applied. Beans are more responsive to potassium, and low potassium levels can lead to reduced root nodulation. There is some evidence that low potassium can predispose beans to Botrytis fabae infection.
Organic is recommended to be applied under the precursor, but is also allowed directly under the main tillage in the fall. Physiologically acidic fertilizers on acidic soils directly under the forage beans, as well as other legumes do not apply, as it negatively affects the development of nodule bacteria.
Phosphate and potash fertilizers are applied under the main treatment in autumn and in top dressing. When placing the beans after precursors after the manure under the vegetable bean is recommended to make mineral fertilizers at a dose of P60K120. On low fertile soils with humus content less than 2 % and without organic fertilizers application of N30-60 provides faster initial growth and increased productivity.
Bean fertilizer requirements (Defra, 2010, UK) depending on soil index (ADAS classification):
- index 0 (very low) – N 0 kg/ha, P2O5 100 kg/ha, K2O 100 kg/ha;
- index 1 (low) – N 0 kg/ha, P2O5 75 kg/ha, K2O 70 kg/ha;
- index 2 (medium) – N 0 kg/ha, P2O5 40 kg/ha, K2O 40 kg/ha;
- index >2 (high) – N 0 kg/ha, P2O5 0 kg/ha, K2O 20 kg/ha.
It is recommended to apply phosphorus fertilizer in rows during sowing. The rates of application are the same as those recommended for grain legumes.
Beans give high yield only on neutral soils. Liming is carried out in autumn under the plowing, the dose is calculated on the hydrolytic acidity. When using dolomite flour liming should be carried out under the predecessor.
Micronutrients
Few micronutrients are important to beans, and those that affect growth or yield are usually corrected by foliar treatment.
Manganese deficiency or unavailability negatively affects chlorophyll production and can cause chlorosis. It also causes marsh blotch, which reduces the quality of seeds or beans for human consumption. This disease occurs most often in highly organic, alkaline or highly calcareous soils and when plants are stressed by drought, excess water or compacted soil. Beans are much less sensitive to manganese deficiency than peas, and disease symptoms are rare.
Magnesium deficiency is also rare except in acidic soils. Symptoms are interstitial chlorosis, but leaf margins remain green. Nutrient deficiency symptoms can often be confused with aphid-borne viruses.
Boron deficiency sometimes occurs in some soils and is best treated with a boron-containing fertilizer. Symptoms include interstitial chlorosis beginning at leaf margins, young leaves may be curled or deformed. Shortened internodes may appear on stems, and all symptoms may appear together.
In alkaline soils in Australia, crops have been shown to respond to zinc; and in acidic soils, molybdenum can be applied as a soluble fertilizer.
Irrigation
Like peas, beans respond well to irrigation when soil moisture is deficient. One of the most limiting factors in bean production during spring planting is moisture deficiency during flowering, which limits bean production in some regions of the world where the growing season is characterized by drought or lack of irrigation. The main effects of moisture deficiency are reduced vegetative growth development, poor seed set, and reduced reproductive nodes due to either flower abortion or seed wilting. If drought occurs late in the growing season, when the pods are filling up, the pod walls may collapse and liquefy, resulting in immature blackened ovaries.
Field beans have shallow rooting compared to winter cereals, which extract moisture from depths of more than 1 meter. The main bean roots can extract water from 40 cm, while a more sparse root system can extract water readily available (spring beans at 70 cm and winter beans at 90 cm deep). Several researchers have shown a yield and growth response to watering beans, but generally a greater response has been obtained on spring beans, possibly because the root system of beans planted in the fall has developed strongly and widely across the soil profile, mitigating the effects of dry soil in the upper root zone (Husain et al., 1988).
Knott (1999) studied the response of spring forage beans to irrigation before, during and after flowering and in combinations for 3 years on sandy soils in the UK. Irrigation increased spring bean yields in all three years, even in the year when a period of drought after flowering caused a 2 t/ha reduction in yields on non-irrigated plots. The yield response of fully irrigated versus non-irrigated field beans to 25 mm of water was 0.34, 0.28, and 0.36 t/ha in each year, respectively. Irrigation during or after flowering gave a statistically significant increase in yield, and there were indications of greater water use efficiency when irrigated after flowering.
Tillage
The system of tillage for forage beans is similar to that for early spring crops.
Cultivation with harrowing is carried out early in spring at the first opportunity to go to the field to save soil moisture. Before sowing, the cultivation with harrowing is carried out to a depth of 8-10 cm with simultaneous incorporation of mineral fertilizers.
After spring harrowing it is sometimes required to carry out deep no-tillage with harrowing.
Sowing
Seed preparation
Las semillas de la judía (V. faba) suelen ser más robustas que las de otras especies de leguminosas, la cubierta de la semilla es más gruesa y el tamaño de la semilla suele ser mayor. Las judías coloreadas contienen taninos en la cubierta de la semilla que tienen actividad antifúngica, lo que puede ser beneficioso para las semillas cuando se siembran en condiciones de suelo fresco y húmedo, donde favorece la infestación por especies edáficas de Pythium spp. Aunque en algunos casos existe una relación entre la emergencia en el campo y la viabilidad de la semilla expresada por la prueba de conductividad, en general la semilla parece rendir adecuadamente si la germinación inicial y la salud de la semilla son satisfactorias. Sin embargo, al ser una semilla grande, es susceptible de sufrir daños mecánicos, especialmente durante la recolección, el procesado y el secado artificial, todo lo cual puede afectar negativamente a la germinación de la semilla. Los daños causados a la semilla por las larvas del escarabajo brúquido (Bruchus rufimanus), que dejan agujeros en la semilla, también pueden afectar a la germinación o exponer a las plántulas dañadas a infecciones tras la plantación.
Una plaga importante de las judías es el nematodo del tallo y el bulbo Ditylenchus gigas, que se transporta en las semillas y, tras la emergencia, las plantas vecinas se infectan con los nematodos. Se recomienda un tratamiento de las semillas contra esta plaga.
Seeds preparation for sowing consists of sorting and calibration, air-heat treatment and dressing.
Air-heat treatment is carried out in active ventilated dryers at an air temperature of 30-40 °C for 3-4 hours.
Before sowing, seeds are treated with bacterial preparations and ammonium molybdate at a rate of 0.25-0.50 g of molybdenum per 1 ton of seeds. Treatment of seeds with Risotorfin should be carried out on the day of sowing; bacterial preparations are especially effective in the fields where beans have not been grown for a long time.
Sowing dates
Forage beans
Sowing of fodder beans is carried out early in the beginning of physical ripeness of soil, at the temperature at the sowing depth of 6-8 ° C.
Researches of Chernigov agricultural experimental station showed the advantage of early sowing terms: the yield of fodder beans at sowing:
- April 4 was: seeds – 2.52 t/ha (protein 720 kg/ha), green mass – 29.9 t/ha (protein 630 kg/ha);
- April 15 was: seeds – 2.26 t/ha (protein 650 kg/ha), green mass – 21.6 t/ha (protein 450 kg/ha);
- on April 25: seeds – 1.72 t/ha (protein 490 kg/ha), green mass – 19.2 t/ha (protein 400 kg/ha).
For conveyor vegetable bean production, the culture can be sown in several terms with an interval of 10 days.
Winter beans
Most winter beans currently grown in Europe were bred in Great Britain and are usually winter hardy, but even they may not survive if conditions are particularly harsh. However, frost damage to the main shoot usually encourages branching of the stem. Winter beans do not require a vernalization period. Growth rate is highly dependent on temperature, solar radiation, and moisture, and although very early sowings (September) and early beans may grow to a height of 20 cm by November, neither they nor later plants make significant growth until warmer weather arrives in spring.
Sowing earlier than mid-October results in earlier vigorous growth, and recent research has shown that beans are more susceptible to chocolate blotch (Botrytis fabae), Ascochyta fabae and exposure to cold, wet weather and frost. Although early sowing delays the flowering date, it does not affect the harvest date. Plant height and lodging increases with early sowing. Winter beans sown late in cold, wet soil from mid-November to early December suffer from high seed loss. Branching is reduced with late sowing. Sowing after December is usually too late, although recent work has shown that winter beans can be grown successfully if sowing is delayed until spring, which is the normal timing for spring varieties (Belcher, 2014).
In several series of experiments in the UK, where beans were sown at different dates, the optimum sowing date was obtained where beans were well established at the first or second node stage by the time they went under the winter. This is usually achieved in the UK by sowing in mid-October to early November (Knott et al., 1994).
Spring beans
To get a good seedbed for spring beans, it is normal to plow the soil in the fall to allow the soil to settle over the winter and create a soil layer in the spring using a minimum of cultivation.
In Europe, more and more spring beans are being produced using non-inversion (no-till and minimum tillage) technologies, either direct seeding over dried stubble or minimum tillage to prepare a level surface before sowing into disturbed soil. In either system, it is important to ensure a weed-free surface and effective straw dispersal.
In most cases, seeding is done early in the season if soil conditions permit. In a series of experiments conducted in the UK, bean yields sown after March began to decline. The relationship between seeding time and seeding rate is currently being studied in the UK, but the results are not yet definitive (Belcher, 2014).
Vegetable (broadleaf) beans
Most bean varieties are sown in the spring, except for those grown for the fresh market, where the need for beans occurs in early summer, and winter-hardy varieties are sown in the fall. For most legumes grown for freezing, the harvest period lasts about 14 days between the time green peas are harvested and processed and before dwarf green beans are harvested. The harvesting period is somewhat dictated by plant capacity, and as with peas, harvesting at critical stages is necessary to maximize product quality.
It is important to get the sowing date right, as this is the only way to ensure the crop is ready for harvest at the right time. Relatively few bean varieties are used for freezing and they have only slight differences in relative ripening rates, making planning a consistent harvest schedule more limited. The effect of sowing date on bean ripening time was studied in the 1970s, when it was found that consistently successful results were obtained by correlating sowing time with anticipated harvest time, using the development curve reproduced in Fig.
This relationship is accurate for most of the UK, although in recent years there has been a shift in production northwards to Scotland, and so there are slight differences in the rate of crop maturity where beans are sown early and soil and air temperatures may be lower.
Sowing methods
There are several methods of planting field beans, including conventional seeding, spreading seed over the surface for plowing, or stubble seeding with no-till or minimum tillage. Usually sowing is done on previously ploughed soil, but in Western Europe sowing is increasingly done using minimum and no-till (non-inversion) tillage. In this way, the sowing depth remains more constant, which allows for an even distribution of the seed and ensures sprouting, since most of the seed is sown to a depth of about 8 cm.
In developing countries or where small areas are grown, spreading seed is a common practice, such as in Ethiopia and Lebanon (Lahoud et al., 1979) and to a lesser extent in other countries. In other countries, furrow seeding, where seeds are placed in divided furrows and then harrowed, or where seeds are individually dropped into small holes made with a small trowel, is done in other countries. Most seeding is mechanized, using variable-depth planters and large-sized coulters to prevent seed damage.
Seed and green mass sowing methods are wide-row with 45-60 cm row-spacing (double-row 60×15 cm), and usual row spacing.
Sowing is carried out by grain seeders with top seeding for less seed trauma.
In the north, in conditions of sufficient moisture and a short growing season on clean fields, the usual row sowing is used. Ripening in this case proceeds a little faster and the yield is higher. For example, in the conditions of Latvia, the bean yield was 2.94 t/ha with the row planting method, and 2.77 t/ha with the wide-row (45 cm) method.
Seeding rates
Fodder beans (Russian practice)
Seeding rate of fodder beans with wide-row method is 400-500 thousand/ha of germinating seeds, in less humid areas – 300-400 thousand/ha. With the row method in more humid areas – up to 600-700 thousand / ha of germinated seeds.
Norm of seeding of vegetable bean seeds at inter-row spacing of 70 cm is 90-100 thousand pieces/ha.
With narrower row spacing the seeding rate increases, also increases the increase in yield. The maximum yield (36.7 t/ha) in the above experiment was obtained with the row seeding method with a seeding rate of 0.62 million/ha of germinated seeds.
Table. Yield of green mass of fodder beans depending on seeding rate and sowing methods (Holt, 1967, Latvia)
| Seeding rate, mln/ha of germinated seeds (kg/ha) | |||||||||
| Yield, t/ha | |||||||||
Winter beans
The pattern of growth varies depending on crop density, with small sprouts of fall beans at the developmental stage needed for winter protection and fast-growing spring bean plants to ensure that a deep root system is established to withstand a possible summer drought. For fall-seeded crops, determining optimum plant density is difficult because the formation of plants surviving until the following spring may be more variable than for spring-seeded crops. In addition, disease pressure from fungal pathogens such as chocolate blotch (Botrytis fabae) can alter crop response to plant density.
Recent work in the UK has shown the effect of early sowing and dense planting on the incidence of chocolate spot disease. With a reduced plant population, chocolate blotch has much less effect on early spring growth. Similarly, planting time affects bean seeding rates, especially when planted in the fall. Beans planted in early fall are more susceptible to chocolate blotch at higher densities (Maguire, 2013). When beans are planted in the fall, low planting densities allow for increased weed competition, increased branching on previously planted crops, and pods form lower on the stem, which increases yield losses due to poor pod harvesting at harvest. High crop densities increase the risk of disease, increase the risk of lodging on soils with high moisture content, and possibly reduce yields due to poor pollination and seed set (Armitage, 2009).
The success of crops is usually judged by their establishment and the number of surviving plants in the spring. Many older winter bean varieties were indeterminant and susceptible to lodging at densities greater than 18 plants/m2. With the introduction of more compact varieties, there is evidence that higher population densities are more cost-effective, and planting densities of up to 25 plants/m2 are common in the UK. As with all optimal density curves, increasing plant density increases the cost of seed, so the optimal economic seeding rate takes into account the cost of seed. The figure below illustrates the relationship between increasing seed rate and yield and shows the yield response and economic response curves. The results are taken from recent work in the UK with the winter bean variety Wizard (Armitage, 2009).
Spring beans
Spring beans have less variability than winter beans, but the timing of spring seeding and rooting methods also affect growth and potential yield. Nott (1994) showed that a system in which seeds are spread over the soil surface and then plowed in early spring has a negative effect on establishment and yield, but sowing with a conventional planter provides a better return due to less loss in the seedbed and higher yields. However, yields are reduced with late spring seeding because of susceptibility to dry soil conditions later in the year. Several reviews of optimum seeding dates for spring seeding in various countries were summarized by Hebblethwaite et al. (1983), with most countries preferring to sow as early in the spring as soil conditions permit.
Much work has been done on estimating optimum densities for spring beans. Ingram and Hebblethwaite (1976) concluded from experiments that a population of up to 86 plants/m2 gives the highest yields, but this is without regard to seed cost. Cleel (1991) reported that the economic optimum for spring beans is 42-60 plants/m2. This has subsequently been confirmed with new compact varieties (Belcher, 2014). When compared to spring beans planted with reduced row spacing, yields increased with narrower rows by about 0.35% per cent per centimeter when row spacing was reduced from 53 cm to 18 cm. Other work has also shown that narrow rows (18-24 cm), especially at high seed rates, produced the highest yields with an increase of 0.42% per cent per centimeter when the row spacing was reduced from 60-75 cm to 12-18 cm. Work in 1986-1988 comparing 12 cm and 48 cm row spacing showed an average yield advantage of 0.15 t/ha, but also showed that the effect was greatest with weak growth and on short-stemmed varieties (Knott et al., 1994).
Broadleaf (vegetable) beans
When growing vegetable beans, sow at a row spacing compatible with the seeder used. Seeds are large, and the number of commercially available seed drills suitable for handling large seeds is limited. Partial vacuum seed drills are usually used for seeding beans. The seeder is equipped with individual units mounted along the toolbar. On each unit, the seed is fed into a furrow made by a set of discs and then pressed down by the next press wheel. Typical row spacing is 45 cm and seed spacing is about 10 cm, with the goal of producing a plant population of 18-20 plants/m2 (Gane et al., 1975). Cultivation on wide rows is also suitable for growing a fresh crop, since access for harvesting is between the rows.
Sowing depth
Large bean seeds are sown in heavy soils to a depth of 4-6 cm, in light soils – 7-8 cm.
Winter beans can be planted slightly deeper than spring crops to avoid damage from rodents or birds.
Crop care
After sowing on light soils and in dry weather it is recommended to roll with ring-spiked rollers.
To control weeds and break the soil crust, carry out 1-3 harrowing before emergence (5-6 days after sowing) and on the sprouts in the midday hours in the phase of 2-3 leaves by light tooth harrows diagonally or across the rows. The second harrowing on sprouts is carried out at the height of plants 5-6 cm (in the phase of 2-4 leaves) using light harrows. The third harrowing is done 5-7 days after the second one. Harrow the crops in the afternoon, when the plants lose turgor and are less brittle. The same conducts inter-row cultivation, with a good moisture content – a little dip, fertilizers.
Between-row cultivation begin in the phase (3) 5-6 leaves with a protective zone of 10-12 cm. For this purpose, wire hoes or sections of rotary hoes mounted on the cultivator frame are used. Inter-row cultivation is carried out 2 times to a depth of 8-12 cm or as weeds appear. During the second and third treatments, ducking is carried out, which strengthens the root system and gives the plants resistance to lodging. The treatments are completed at a plant height of 50-60 cm.
Weed control
In the early stages, forage beans are not very competitive against weeds. Later on, high-growing bean varieties compete well with most weeds, although climbing species such as hillweed or cleavers (Galium aparine) can still be a problem.
In experiments conducted in the UK on spring field beans, where weed infestations ranged from 79 to 157 plants/m2, the yield increase achieved by controlling broadleaf weeds with preemergence herbicides was 13% to 44%, averaging 21% (Knott et al., 1994). This covered convincingly the cost of herbicides and their application. At world market prices, the “breakeven” yield is about 9%. Therefore, it is important to control weeds in spring bean crops.
Yields have not always been sufficient to cover the cost of post-emergent herbicides against broadleaf weeds. From a yield-only standpoint, weeds need to be controlled on spring beans, but in several other experiments yield increases due to weed control were not achieved when weed numbers were below 50 plants/m2. However, since in most cases preemergence products are used for weed control, the weed population at the time of application is not known.
Cultural control methods
Stubble-cleaning and seed-rowing methods are commonly used in bean cultivation, although they do not reduce populations of weeds growing from deep within, such as oilseed rape residues and field thistle (Sinapis arvensis).
Mechanical tillage in crops has the disadvantage that it does not control weeds in the row and may require more than one operation. Harrows are often used on winter beans, and if the growing points are damaged, the plants compensate by producing new branches from the base. However, beans must be grown in wide rows (40 cm) to make it easier to pass between them.
The frequency of tillage required for adequate weed control depends on the date of sowing, the number of weed species, and growing conditions. For spring beans, early weed removal by cultivation 4 to 6 weeks after emergence is important. For winter beans, more frequent tillage may be necessary because weeds need more time to germinate. Weeding with an Einbock finger weeder can also be used, especially on spring beans before they grow too tall.
Biofumigants
Biofumigants have been used for many years, and considerable research is continuing on the use of these techniques on annual crops. The technique is based on applying fresh, mulched plant material to the soil that releases several substances that can suppress soil-borne pests or diseases, and in some cases it is claimed to suppress weeds as well. Plants of the genus Cabbage (Brassica) are particularly active sulfur accumulators and synthesize significant amounts of sulfur-rich glucosinolates. Damaged leaves secrete myrosinase enzymes that break down glucosinolates into several products, including isothiocyanates (which are very toxic). Work has shown that these products are active against some soil-borne diseases and pests, but there are claims that weed suppression can also be achieved.
Growing a Brassica cover crop for use as a biofumigant involves establishing a fall crop, usually mustard, particularly brown mustard (Caliente) (Brassica juncea), although other members of the crucifer family (Cruciferae) can also be used.
While the use of such cover crops has several advantages in farming, such as providing a source of nutrients for newly developing crops, helping to improve soil structure by adding organic matter, and having some effect in suppressing pests such as nematodes, there is little reliable information that this technique can become a sustainable weed suppressant in pea and bean crops. It has been suggested that crucifers may have allelopathic effects on weeds, and reports from Europe and North America also suggest that crucifers may be used for integrated weed control (Tollsten and Bergstrom, 1988; Turk et al., 2005). However, there is no reliable evidence of weed reduction in the growing crop (Haramoto and Gallandt, 2005a,b). Similarly, there are reports of suppression of A. myosuroides with a cover crop of mustard preceding spring sowing of horde beans (Jim Scrimshaw), but the effect was not repeated on beans from year to year, although other work on winter cereals has shown significant suppression. This may be due in part to a lack of glucosinolate stability in the soil during weed germination, or other factors may be involved.
Herbicides
In the UK and elsewhere in Europe, preemergence residual herbicides must be used because only one postemergence herbicide is available.
No herbicides are available to control thistles and sorrel (Rumex spp.) because translocated substances such as clopyralid or MCPB and MCPA damage the beans. Most preemergents require a minimum depth of application, and the dosage may depend on the soil type.
Where the problem is expected to be with the solanaceae (G. aparine), clomazone in a tank mixture is effective. Imazamox and pendimethalin or prosulfocarb can be applied pre-emergence on both spring and winter beans, but linuron can only be used on spring crops. On winter beans, propisamide or carbetamide provide limited control of broadleaf weeds, but they are used primarily to control grass weeds, especially where blackgrass populations are resistant to other graminicides. Bentazone is the only postemergence weed control agent for broadleaf weeds. Triallate is often used to control wild oatgrass, as well as quizalofop or tepraloxidime (PGRO, 2016).
Pre-emergent herbicides can be sprayed with Prometrin at a rate of 3-4 kg/ha.
For Vicia and Phaseolus, bentazon is the only material that is safe to use as a post-emergent herbicide to control broadleaf (dicotyledonous) weeds. The selective action of bentazone may be due to differential retention and uptake as well as the ability to metabolize bentazone (see Peas for details).
Orobanche crenata
Orobanche crenata is an obligate parasite that can occur on several legumes and some Umbelliferae in cultivated fields and sometimes in gardens. It is found in the Mediterranean region, southwest Asia, and as far east as Iran, and along with a related species, the Egyptian infestation (O. aegyptiaca) is considered a serious problem in Egypt, Jordan, Tunisia, Lebanon, and Italy; it is also common in Morocco, and there are reports of serious problems in Spain, Turkey, and Malta. Estimates of losses of infected beans range from 5% in Spain to 20-60% in Morocco. In several countries, O. crenata is a notifiable pest (quarantine weed) for which strict import controls exist. It has also recently appeared in the United Kingdom (PGRO, 2015b).
O. crenata produces typically unbranched flowering stems up to 100 cm tall, devoid of chlorophyll. The base of the stem underground is usually swollen and tuberous. The inflorescence, which occupies up to half the length of the stem, bears many orchid-like flowers arranged in spikes. Each flower may contain a capsule which may contain hundreds of seeds. O. crenata establishes a connection with the host root within days of germination, stimulated by root exudates of the host. Seeds must be in a moist environment and at a suitable temperature for several days before germination. Otherwise, mature seeds may remain viable dormant for many years.
Because Orobanche spp. is entirely host-dependent, the impact on the host is proportional to the biomass of the parasite. Symptoms of the presence of O. crenata may not be noticeable until after the parasite has appeared; the reduction in pod wilting and seed development is certain and can be serious. Beans may wilt and, in severe cases, die.
There is no single effective method of control. Basic approaches include phytosanitary measures to control seed and plant movement. Cultural control methods should be used in combination, as no single method will have maximum effect. Subcrops, where the host plant is sown and then plowed before the parasite multiplies, can be used. Some effect has been reported from the use of soil sterilants such as dasomet, which gives a degree of control. Breeding efforts are currently underway to develop resistant varieties of Vicia (Rubiales, 2014).
Features of cultivation of winter and spring forms
Winter beans can be sown either in no-till or after plowing. Seeds are planted at a lower density than those grown in the spring because cool winter temperatures encourage the plant to produce lateral shoots that later develop into fruiting stems, whereas beans planted in the spring usually produce only one or two lateral shoots.
Fall beans are usually grown in heavier, wetter soils where it is not possible to create an acceptable bed for spring planting. Winter beans can also be affected by birds or frost, although they can tolerate temperatures as low as -12°C or lower if there is snow cover.
Modern varieties tend to have large seeds, so conventional seed drills for cereals are not always suitable; however, in the UK and France, where winter beans are mostly grown, modified direct seed drills and deep openers have been used successfully. Winter beans can also be infected with leaf spots such as chocolate blotch (Botrytis fabae) and leaf and pod blotch (Ascochyta fabae).
Some high-growing varieties may lodge in severe weather, but modern varieties are less indeterminant and stem strength is improved.
Spring beans are less likely to suffer from brown spot disease, but it can be more susceptible to powdery mildew (Peronospora viciae), aphids, and aphid-borne viruses.
Whatever time of year the beans are planted, winter and spring varieties tend to mature at the same time, so only in extreme conditions can harvesting be delayed until later in the fall, allowing the grain harvest to be completed before the beans mature.
Harvesting
Forage beans
To accelerate maturation, a month before harvesting, pruning, which is the removal of 10-12 cm of the top of the main stems. This method also reduces the infestation of plants by aphids.
Table. Effect of pruning on yield and seed quality of fodder beans (All-Russian Research Institute of Fodder)
| Without pruning | ||||
| Pruning at 10-15 cm, carried out on July 22 |
Removal of leaves also affects the acceleration of bean ripening. To do this, plants are sprayed with preparations that cause leaf drying and leaf fall, such as 10-15% solutions of nitrate or ammonium sulfate. Crops are treated 2-3 weeks before harvesting.
In some seasons, pod maturation is uneven, and the upper pods remain green longer. Bean pods turn black and the seeds become dry and hard earlier than the stems of most plants. The pods are easily threshed when the moisture content is 16-20%, but you usually need to wait until most of the stems are brown and dry. Overdrying can lead to shattering and heavy losses when harvesting.
At full maturity, beans tend to crack and seeds tend to shatter, especially in dry years. Therefore, the preferred method of harvesting two-phase, start harvesting when 25% of the bottom beans are dark. The seeds ripen well in dry and warm weather and retain their high sowing qualities.
High-stemmed, non-legume varieties may be harvested in a single- or biphase. The two-phase harvesting method preferably consists of depositing the cuttings in a high stubble. The drying of swaths lasts 5-10 days, over-drying leads to losses from cracking of beans and shattering of seeds. The threshing of the swaths is carried out at a drum rotation speed of 400-500 rpm.
When 85-90% of the beans are blackened, harvesting is carried out in a single phase. In this case, defoliation is carried out 2-3 weeks in advance.
Because of the large size of the seeds, the rotation speed of the harvester drum should be minimal and the clearance of the tine should be maximum.
After harvesting, the beans can be dried with ambient or slightly heated air until the optimum storage condition of 85% dry matter of the beans is reached.
Dry bean legumes can be used as livestock feed and can be pressed into bales for storage after harvesting.
Once harvested, beans can be stored satisfactorily at 14% moisture content. If drying is required, the method used depends on the market. Field beans grown for seed or premium niche markets require drying and storage so that germination and quality are not affected by damage such as seed coat cracking or seed splitting. For the animal feed market, the only criteria are maximum moisture content, level of impurities and absence of mold, so beans do not require such gentle drying. Flour can be pasty if insufficient moisture is removed from the center of the beans, and it can go rancid if stored for long periods of time.
Processing
Beans are usually cleaned by specialized traders before use, and the procedures are similar to those used in pea cleaning. Spotted, broken, and foreign impurities are removed. If the beans are intended for human consumption, they are cleaned in a drum cleaner to remove beans that have been damaged by the bean burr (Bruchus rufimanus).
Vegetable beans
The maturity of the beans is assessed in the same way as in peas, using a tenderometer. However, the tenderometer is not an absolute indicator of quality because its reading is an average of all beans in a sample, which may contain beans of different degrees of maturity. It has also been found through organoleptic tests that optimum quality for a particular variety can be observed at different ripening times under different growing conditions; similarly, optimum quality can be observed at different ripening times for different varieties. Under dry conditions, the skin can become tough faster as chemical processes take place in the beans. In the absence of more critical methods, a combination of tenderizer and organoleptic tests is often used.
Beans are usually harvested directly in the field with green pea harvesting machines (winers) equipped with modified picking drums to handle the taller crop, or they are first cut and left in windrows for 24 hours to allow the crop to wither slightly, which in some situations can help with threshing.
The beans are unloaded from the mobile viners into tanks for transport either directly to the plant or to a cleaning and cooling line at the farm. They are then transported in sealed containers to reduce discoloration of the green beans. Before blanching and freezing, the beans are cleaned again at the plant.
If unripe seeds will be used for food, the beans may be harvested when the seeds have reached full size for the variety but are still in milky ripeness. Bean yields at technical maturity are 10 tons per hectare and grain yields are 4 tons per hectare. Beans are harvested as they mature, in 3-4 stages, with an interval between harvests of 8-12 days. They are removed by a downward swift movement, taking care not to damage the plant.
Beans can be canned in the same way as peas. In extreme cases, when no suitable crop is available near the plant, canning can be done using frozen beans. As with frozen peas, the beans are contracted to processors, and sales are usually made by the processor to retailers.
String (broadleaf) vegetable beans for hand picking are usually grown in wider rows to provide access for pickers. Maturity is sometimes assessed on a tenderizer, but often the criteria for harvesting are based on visual inspection of the pods, their length and degree of fullness, and samples are taken to determine seed size and seed-to-pod ratio by weight. The fresh market requires a pod width and length of a certain size, a minimum number of beans in the pod and a seed to pod ratio of about 35%. The pods are hand harvested and delivered to the packing house in boxes before being pre-packed and transported to the retailer.
Vegetable pods can be fully harvested during the milk ripening stage, when the pods are juicy and the grains have reached 1 cm in size. At this time, the beans break easily and reach a length of 5-7 cm, the outline of the seeds begin to show through the skin of the bean, and the scar of the seed has not lost its white or green color.
Desiccants
Desiccation for forage (dry) beans is usually rarely used.
Preparation Reglon Super, spraying crops when the lower beans turn yellow and the seed rumen turns black.
Diseases
Bean powdery mildew (Peronospora viciae)
Bean powdery mildew (Peronospora viciae), also affects peas, but it has not been shown that isolates of bean powdery mildew can be successfully inoculated on peas, and it is believed that individual pathotypes exist among P. viciae populations that may be specific to V. faba. The disease has been reported in many areas of the world with temperate climates, but mainly where early growing conditions are cool and wet.
Symptoms of the disease resemble those of pea powdery mildew infestation. The initial infection begins with a soil inoculum consisting of oospores that infect germinating bean seedlings. As a result, the infection develops systemically on the seedlings, producing stunted, pale plants on which oospores form from mycelium on the underside of the leaves. The infection spreads as a secondary infection to surrounding plants, often ending in complete distortion of the growing apex, covered with the characteristic gray-lilac mycelium. It has not been established that the pathogen is transmitted via seed.
Conditions conducive to infestation have been determined by a combination of temperature and humidity (Biddle et al., 2003), leading to the development of a prediction system. A system used by growers in the UK to determine the risk of infestation and a decision support system for spray application has been made available online for UK growers (CropMonitor).
Bean powdery mildew can be controlled with phenylamide fungicides and seed treatments can also be effective. There are several V. faba varieties that have higher field resistance to the disease than others, and this characteristic is included in the recommended list of bean varieties in the UK (PGRO, 2015).
Chocolate spot (Botrytis fabae)
The causative agent is Botrytis fabae as well as Botrytis cinerea.
The disease develops during the summer period with long wet and cloudy periods. It is found in all regions of the world where horse beans are grown, but causes serious losses only under favorable conditions. Yield loss due to defoliation and reduced photosynthetic area is a major problem, and beans for the fresh market, harvested as whole pods, can be spoiled by spotting and dampness that appears on infested plants.
Symptoms of chocolate blotch differ from other leaf and pod spot diseases in that there is no obvious formation of fruiting bodies of the fungus, as in the case of Ascochyta fabae.
Fall crops are more susceptible to infection because it can begin in the fall and remain low until spring, when weather conditions favor development. High planting densities promote disease development, and planting date also affects the amount and aggressiveness of the disease that develops.
The use of fungicides to control chocolate blotch is routine in most temperate climates, and reliance on fungicides is complete because there are no significant differences in varietal resistance to this disease. Timing of application is key to effective control (Gladders et al., 1991).
Source: commons.wikimedia.org©Jerzy Opioła (CC BY-SA 4.0)
Source: commons.wikimedia.org©Jerzy Opioła (CC BY-SA 4.0)
Leaf and pod spot (Ascochyta fabae)
Leaf and pod spot, or brown spot.
Pathogen: the fungus Ascochyta fabae (Ascochyta vicia fabae (Speg.)), a relative of the pathogen that causes leaf and pod spot in peas, is specific to beans and is the only pathogen that seriously affects their yield and quality. The infection can lead to plant death.
On beans, the disease appears as deep rounded or oblong, brown spots with a dark red rim and fruiting bodies. Damaged leaves wither prematurely, stems become crooked, plants stunted in growth, beans rot and produce stubby seeds. Affected seeds with brown spots lose germination.
Transmitted mainly by seeds and develops on seedlings soon after emergence. Pycnidia formed in pockets of disease on stems, leaves, or pods contain spores that are released and splashed by rain or water droplets. Internal infestation can occur, resulting in deep seed infestation. Spores can also be transmitted by wind from pycnidia formed on overwintered infested crop residues, where the sexual form of A. fabae (Didymella fabae) develops in the fall and winter (Jellis and Punithalingam, 1991).
Chemical controls were largely unsuccessful, and the health of V. faba beans in the United Kingdom was maintained by strict certification procedures until the mid-1990s. Since then, breeders and seed growers have maintained voluntary standards. Resistance to A. fabae was identified in winter beans in the United Kingdom several years ago (Bond and Pope, 1980), and since then efforts have been made in Europe and other countries to develop fully resistant varieties.
Brown rust (Uromyces fabae)
Brown rust, English Brown rust, is common in most parts of the world where beans are grown and has become a major cause of yield loss in both field (forage) and broad (vegetable) beans. Beans, both spring and winter varieties, can be affected at any stage of the growing season.
The causative agent: the fungus Uromyces fabae.
Leaves become infected from the time of flowering, but the most serious infections can begin late in the season, after a period of warm days and cool nights with high humidity. Because of the effects of weather conditions, later maturing beans planted in the spring are often more susceptible to infection, although some seasons may also affect fall crops. Rust spores can persist as teli in a semidormant state over the winter on crop residues or on volunteer beans.
Rust causes partial defoliation and loss of photosynthetic area, resulting in significant yield losses, especially if infestation begins at the pod development stage. Pustules may form on stems and pods, and heavy infestation causes poor seed development. In the case of vegetable beans, spoiled pods may become unmarketable.
Although rust control with systemic fungicides is effective, there are some differences in susceptibility between varieties, especially in Europe, where some spring bean varieties are more resistant than others. Incomplete resistance is common, but hypersensitive resistance has only recently been identified (Rojas-Molina et al., 2010), although varieties with complete resistance have not yet been developed (Adhikari et al., 2012).
Source: commons.wikimedia.org©Jerzy Opioła (CC BY-SA 4.0)
Viral diseases
Beans (V. faba) can be infected by several viruses, some of which are seed-borne, but most of the 18 or so viruses described worldwide are transmitted by aphids or other insects (Kumari and van Leur, 2011). Viruses such as bean leafroll virus (BLRV), which is transmitted by pea aphids and black bean aphids, and pea enation mosaic virus (PEMV), which is also transmitted by pea aphids, are common in Europe. Often the two diseases occur together, and infected crops exhibit a variety of symptoms including classic leaf curl, top leaf wrinkling, development of translucent leaf spotting, deformed and stunted pods and internodes that are often confused with symptoms of manganese deficiency.
In Africa and the Middle East, one of the most common viruses is Necrotic Horse Bean Yellowing Virus (FBNYV), which is effectively transmitted by Aphis craccivora from a number of wild host plants. Western beet mosaic virus is common in some areas in Australia, and pea mosaic virus, carried by aphids from nearby infested pea crops, can also result in quality loss due to seed coat defects.
So far, there are no reports of varietal resistance to any of the common viruses, so the focus for control and management is on crop hygiene, weed control, and pesticide application.
Pests
Stem nematode (Ditylenchus gigas)
The stem nematode (Ditylenchus gigas), formally known as the “giant” race Ditylenchus dipsaci, is a free-living nematode that can survive in soil for several years. It has been found on Vicia beans in many regions of the world, especially where V. faba has been grown for many years. This species is specific to Vicia beans, and although other nematode species (D. dipsaci) can affect beans, they do not cause serious yield losses.
Damage is often observed when plants reach flowering, but young seedlings may show severe symptoms even before that, especially in wet conditions. Plants are stunted, stems thicken and twist. Blisters often appear on the stem, which may become reddish in color. The infected stem may collapse. Leaves become deformed on the petiole, and growth points may be similarly affected. The pods do not develop, and if seeds appear, they are black and wrinkled, or the seedpods may be discolored in small patches. Affected plants are found singly or in large areas of the field, and both winter and spring beans may be affected.
The effect on yield is severe when pest numbers are high. In beans destined for human consumption, seeds may be discolored and their presence may result in rejection by processors.
Stem nematodes are carried by both seed and soil. Once infested, the nematodes move within the plant and multiply in the tissues, after which some of them move into the developing seed and mass under the seedling. They then survive desiccation and survive inside the seed for 2 years. Infested seeds can be transported, and when planted, the nematodes re-infect the developing plant and the populations move to surrounding plants, thereby causing a new infestation in clean fields.
Since the pest can be seed-borne, the only means of control is seed production in uninfested fields and strict seed testing. The test method is based on the extraction of nematodes from seeds by soaking in water for 24 hours and microscopic examination of the soaking water (Augustin and Sikora, 1989), and this method is used by many seed testing laboratories. Molecular testing procedures are currently being evaluated by several European researchers. If nematodes are found in the sample, the seed should not be used for sowing (PGRO, 2015). There have been attempts to screen V. faba lines from the ICARDA germplasm collection for resistance to D. gigas, and breeding work is at an advanced stage in developing a field bean variety with some resistance to the nematode (Stawniak, 2011).
Black bean aphid (Aphis fabae)
Black bean aphid (Aphis fabae) is the main pest of forage beans and sometimes peas, but can occur in large numbers on beans, spinach and sugar beet, where populations infesting the underside of leaves can become chlorotic and shriveled.
A. fabae is found in many countries, including Scandinavia, Europe, Asia, the Middle East, parts of Africa, North and South America, but is not common in the tropics. The related black aphid, Aphis craccivora, is common in warmer countries, where temperatures of about 24°C are more favorable for its development. This species has a wide host range and includes most grain legumes and plants.
A. fabae colonies grow rapidly on bean plants, especially on the growing shoot, where they cause direct food damage by reducing the number of flowering pods and apex growth. In addition to feeding, they are vectors of viruses, including bean leafroll virus (BLRV) and yellow bean mosaic virus (BYMV). Together with pea aphids, they can also carry pea enation mosaic virus (PEMV), which in combination with BLRV can cause significant yield reduction. Yield reduction depends on the degree of infection, but yield loss is high where colonies are dense around flowering and pod nodes.
The effect of viral infection on yield and quality can also range from minor to severe with distortion and poor seed development or seed coat staining resulting in crop rejection.
Aphids migrate to bean crops in late spring or early summer and colonize plant tops before developing large dense colonies of many hundreds of individuals.
After colonization, winged aphids leave the crops and lay eggs on wintering hosts, including the spindle aphid (Euonymus europaeus). A. craccivora has a similar life cycle to A. fabae, but the woody overwintering hosts are laburnum (Laburnum anagyroides) and broom (Sarothamnus scoparia).
Control of both species is based on insecticide treatments when colonies are first detected and before flowering, since early migrating aphids can begin transmitting the virus immediately after feeding begins.
Source: commons.wikimedia.org©Rasbak (CC BY-SA 3.0)
The bean seed beetle (Bruchus rufimanus)
The bean seed beetle (Bruchus rufimanus) is the most damaging pest of V. faba forage beans and is present in many temperate countries.
The main impact on beans is infestation of the developing seeds by the larvae and pupae of this insect. Fresh beans may be spoiled by larval entry holes that become visible after the pods are opened. Beans will also contain larvae at this early stage, and produce for processing or fresh market will be unsuitable for sale. In the dried crop, the presence of pupae or unhatched adults creates problems with exporting beans for human consumption, and beans with exit holes are also unsuitable for high quality markets unless they are removed mechanically during cleaning.
Unlike closely related bruchid beetles, B. rufimanus has only one generation per year and relies on its development on a growing crop. It is not a pest of stored products. Adults arrive on beans at the beginning of flowering and feed on pollen for 2 weeks before becoming sexually mature. At this point, the females lay eggs on the developing pods; after a few days, larvae hatch from the eggs and burrow into the pod and into the developing seed. The larvae feed on the seedpod until the seed and larva reach maturity. At this stage, the larvae pupate and emerge as adults shortly before or just after harvest, leaving round exit holes in the beans. The adults then migrate to overwintering sites, which include wooded hedges and tree bark in shrub vegetation around the field.
Attempts have been made to establish a system to monitor the presence of bruchids on crops, and there has been limited success using cone traps with baited floral volatiles, which have been effective in capturing adults when they move into crops, but not attractive enough to compete with crops after flowering begins (Ward and Smart, 2011). France has decision support systems for bean growers to determine when to spray, and the UK has recently developed a similar web-based system (Bruchidcast). Both systems use daily temperatures to determine the period of bruchid activity so that insecticides can be applied during the oviposition period.
Limited screening for resistance to B. rufimanus in Vicia beans has been done, but no resistant varieties have yet been developed.
Source: commons.wikimedia.org©Francisco Welter-Schultes (CC0 1.0)
Seed production
Beans are facultative cross-pollinators; pollen is carried by bees and bumblebees. Depending on the variety and weather conditions, cross-pollination can be as high as 35%. In seed growing, the spatial isolation between different varieties should be at least 1000 m apart in the open field and at least 500 m apart in the protected field.
Variety sweeps are carried out on seed crops:
- 1 – at the phase of 2-4 leaves, plants differing in growth and development, shape and color of leaves are removed;
- 2 – At the phase of flowering, remove the plants lagging behind and ahead in development, differing in height, color of flowers and leaves, the shape of leaves;
- 3 – remove plants at the phase of 2-4 beans in the phase of biological ripeness, which differ in the angle of attachment of the bean to the stem, the color of the seed rumen, the color of the seeds.
The main method of harvesting beans for seeds is direct harvesting. Harvesting is started when 75-90 % of beans are dry and seed humidity does not exceed 25 %. Harvesting should be carried out in the morning and evening hours at low temperature and humidity of not less than 70%, which reduces the shattering of the seeds. Postharvest processing and storage of seeds are carried out as well as for beans.
Breeding
History of modern varieties
Until recently, the scientific approach to breeding of horse bean was practically absent. Perhaps this is because it is a cross-pollinated species, where pure line breeding approaches are not relevant, nor are there easily developed Mendelian trait markers. Therefore, cultivars grown and sold have not often been precisely defined or clearly distinguished from one another. It is thought that V. faba may have descended from two or three ancestors of the genus Vicia, V. narbonensis, V. galilaea, and V. hyaeniscamus, but there is very little evidence of its relationship to these three species (Ladizinski, 1975). Nor has it been possible to cross V. faba with any of these species, and so far this limits the variability available for breeding V. faba varieties, especially since V. narbonensis has good resistance to some common bean diseases.
In its domesticated form, V. faba remains a distinct species, although some of the small-seeded species are known as V. faba subsp. minor and the larger ones as subsp. major or equina. However, there is no evidence that there are any barriers to gene flow between seed size classes, so botanically they should not be classified as subspecies, since arbitrarily defined seed size ranges are more or less simply marketable classes. The sources of variation that do exist in V. faba are in the broad gene pool of its domesticated species, helped to some extent by the popularity of the bean, especially the large-seeded bean, as a vegetable for the vegetable garden and as a field crop harvested dry. There are some mutational changes caused by chemical or radiation treatment (Sjodin, 1971), but in general modern varieties of V. faba have been created by conventional breeding methods.
Recent development of di-haploids by anther and pollen culture has proven to be applicable to V. faba, and at least one variety is currently on the market.
Although the flowers of the plant are somewhat autofertile, V. faba is partially allomagic and can be crossed by cross-pollination by insects, mainly bumblebees (Bombus spp.). This has several important implications for bean breeding that should be noted. The development and maintenance of pure lines requires the complete elimination of pollinators, which is a major overhead for the breeding program and makes it more or less impossible to produce pure inbred varieties. The use of male sterility to maximize hybrid viability has been previously studied, but a commercially viable hybrid production system has never been established. A compromise solution is to exploit the natural tendency for one-third to two-thirds of seeds to be produced by outcrossing, by creating so-called “synthetic” varieties in which several founder individuals that share some characteristics but are by no means homologous are allowed to cross freely, giving a degree of hybridity that can decline over several generations of reproduction in the absence of optimal pollinator populations (Obiadalla-Ali et al., 2015).
Beans are capable of adapting to environmental conditions, and because they were more widely grown in areas north and south of the Mediterranean, varieties emerged from the use of their adaptations rather than specific breeding methods. Adaptations include winter hardiness, reduction of pod shattering (dehiscence), seed size, and seed color changes. Recently developed bean varieties include varieties with winter hardiness to be sown in the fall, varieties with spring sowing, more determinate stem growth to reduce lodging, medium seed size, and light brown or green seed color. The green seed character as a result of persistent chlorophyll has been identified as the only recessive gene-determined trait and has been used in vegetable beans in China and other countries.
Despite its popularity since domestication, the area planted with beans has been very much reduced during the last century due to the introduction of mechanical labor, since horse beans were the main ingredient for feeding oxen, horses, and mules. Also, very little effort was put into plant breeding to develop new varieties that would be better adapted to modern agriculture. This meant that beans had low yields and poor yield stability, especially during periods of drought or excessive moisture, uncertain growth resulting in excessive stem growth and susceptibility to lodging, relatively low resistance to disease, and the presence of anti-nutritional factors, which reduced their suitability as feed for many livestock species. However, as interest in this crop began to increase due to the desire to produce more sustainable sources of plant protein and the value of grain legumes in arable rotations and in less developed agricultural systems, significant advances in both breeding and agronomy have recently been made.
Modern varieties have a more determinate habitus (i.e., cessation of vegetative growth at the onset of flowering and pod set), low anti-nutritional factors, and increased resistance to the most common diseases, including ascochytosis (Ascochyta fabae), rust (Uromyces viciae-faba) and powdery mildew (Peronospora viciae), and resistance to broomrape (Orobanche crenata). Advances in the study of genomics allow the creation of a gene map, marker-assisted selection is underway, and work is underway to study synteny with other legumes, such as peas and Medicago truncatula.
The full genetic potential of V. faba is still being studied, including leaf architecture, pod wall characteristics, stem determinancy, factors affecting flower set and pod set, and aspects of seed quality such as protein content and reduction of anti-nutritional factors including tannins (Stoddart, 1986).
Because of the indeterminant habitus, the stems can produce excessive growth to the detriment of the reproductive nodes. Competition for light and pollinators results in poor flower retention and smaller pods at the top of the stems, making the crop slow to ripen and difficult to harvest. A variety with a terminal inflorescence (type ti) was proposed to breeders. This variety had a stiff stem with the inflorescence at the top of the stem. However, this was somewhat extreme and the type was less able to adapt to variable climatic conditions during growth and was not widely distributed. Work is currently underway to identify markers for determinant types (Alvila et al., 2007).
The most important fungal diseases of leaves are chocolate blotch (Botrytis fabae), Ascochyta fabae, and Uromyces viciae-fabae. The soil root fungi Rhizoctonia solani and Fusarium occur in some areas, especially in soils with a long history of horse bean cultivation. Botrytis occurs in a wide range of growing conditions; it is often a very serious threat, but there is very little information on the source of resistance, although several less susceptible bean genotypes are known (e.g., ICARDA lines originating in Ecuador). For Ascochyta and Uromyces, specific resistances are known and molecular markers have been developed. Downy mildew causes other, less well-studied leaf blight diseases of V. faba, but, as with peas, there are several races of the pathogen and complete resistance to downy mildew is unknown. Breeders rely on selecting less susceptible varieties for commercialization. Viruses can be a frequent problem, and viral diseases can appear in epidemic form and become serious. Pea enation mosaic virus, yellow bean mosaic virus, bean leafroll virus, true bean mosaic virus and bean spotted virus are common. The impact of aphid-borne viruses can be reduced by effective plant protection methods, but seed-borne viruses can pose a major problem. The most important pests are Aphis fabae (black aphid) and Acyrthosiphon pisum (pea aphid). In addition to direct food damage, transmission occurs when aphids are introduced early in the growing season and useful resistance is unknown.
Fab beans can be infected with the stem nematode Ditylenchus gigas, which is widespread and common, especially when nematode-infected seeds are used. Recent work has identified potential breeding material that demonstrates resistance to the nematode, and developments are underway to evaluate the potential of this material to provide a reliable level of resistance. Broomstick (Orobanche crenata) is a parasitic plant that damages legumes and other crops in the Mediterranean basin and the Nile Valley. Partially resistant genotypes are available; the trait shows quantitative genetic variability, and three quantitative trait loci (QTL) for resistance have recently been identified (Torres et al., 2006). Several sources of resistance to root rot are known. Varieties with low tannin content in seed coat have been developed, but because these varieties are usually white-flowered, the difficulty of propagating homozygous rootstocks makes commercial introduction very costly.
Cross-pollination by bees and other flying insects is about 50%, with a large genotypic and environmental component of variation and pronounced heterosis, where heterozygous types show on average less outcrossing; and in the open field, seed production suffers from cross-pollination contamination unless spatial isolation and clean lines are used.
Despite limitations in breeding perfect beans, breeders have made considerable progress in developing a steady stream of new varieties for commercial production. In Europe, significant progress has been made in improving yields, and the recently bred varieties Fanfare and Vertigo have clearly demonstrated this improvement and are now being grown on a significant scale.
Forage bean varieties
Forage beans grown for dry collection (field beans) are usually either winter beans, when sown in the fall and are more frost-resistant, or spring beans, which are usually sown as early as possible in the spring to reach their full yield potential.
Seeds are primarily used as a source of plant protein for animal feed and aquaculture, although dried horse beans also form an important part of the human diet in Africa and the Middle East. The quality of the seed for the human consumption market is important in that the beans should be plump, not flat, with an even light brown skin color and a pale colored (so-called white) hilum. Since European and Australian producers are interested in supplying these markets, most varieties of horse bean have been selected for these characteristics.
There are no special color or shape requirements for animal feed, and beans can also have black cores, although the presence of heavily decomposed broken seeds or high levels of insect damage can reduce the value of the crop. The presence of anti-nutritional factors such as tannins was thought to have a negative effect on the high inclusion rate of beans in feed, but recent studies have shown that the presence of tannins from beans in swine diets does not result in negative growth or digestibility in fattened pigs.
There is a small market in the U.K. for feed for racing pigeons, for which small round seeds are required. One variety, Maris Bead, has been commercially grown for this purpose since 1964. Because of the very small market for these beans (known as teak beans), no breeding work has been done in recent years.
Recently, varieties of horse beans with improved nutritional properties have been developed, including varieties without tannin (such as Gloria) and with low levels of vicin and convicin. These two glycosides have been linked to poor digestive rates in animals and a disorder known as favism in humans, when a person has a deficiency in glucose-6-phosphate dehydrogenase activity.
These low-vicin varieties have been registered in France by INRA (Institut National de Recherche Agronomique) and are known as Fevita varieties. Some of these may be preferred by specialized animal feed producers, although there seems to be no commercial advantage to these types yet in the UK and Canada.
Both spring and winter bean varieties are in field variety trials in the U.K., as well as in several European countries, Australia, and Canada. Existing varieties are listed in the UK on the Recommended List and are updated annually.
Vegetable (board) bean varieties
There are two main types of beans within the V. faba there are two main types of beans based on their uses, which are described here: the type that is harvested at the immature green stage, when the seeds are extracted from the pod and consumed as a vegetable; and the type that is harvested when fully mature to produce dry seeds, used for a number of human or animal food uses. Vegetable beans, known as broad beans, are grown either for the fresh market or for large-scale commercial freezing or canning. Varieties have been developed based on the appearance, flavor, texture and color of the immature seeds, which can range from pale green to dark green, from very large in size or slightly flattened in shape to small and almost round beans. Harvest height also varies between varieties. Very low-growing dwarf varieties, such as Sutton, have very few vegetative nodes and begin their reproductive stage on nodes that are still very low to the ground. Often these varieties are more precocious than the taller varieties. The pods form into dense inflorescences around the stem. Some varieties are more frost-resistant and can be sown in the fall for an early harvest. Seed set can be a problem for varieties sown in the fall, as insect activity during flowering can be low during the cool season, which can lead to uneven seed set in the pods. The Aquadulce variety is often sown in the fall for the fresh market.
Two basic types of beans are grown: those with white blossoms, which are suitable for canning; and those with colored blossoms, which are suitable for freezing, although most varieties grown for freezing have white blossoms.
Beans for the fresh market can have either white or colored flowers. Colored flowers indicate the presence of leuco-anthocyanins, which break down into colored polyphenols when cooked, yielding pink or brown beans in a cloudy brine when canned. The frozen market requires beans with uniform seed size and color, while the fresh produce market requires pod width and length in certain size ranges, a minimum number of beans per pod, and a seed-to-pod ratio of about 35%.
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Horticulture/P.P. Vavilov, V.V. Gritsenko. Vavilov. ed. by P.P. Vavilov, V.S. Kuznetsov et al. – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and Tutorials for Higher Education Institutions).
Fundamentals of agricultural production technology. Farming and plant growing. Ed. by V.S. Niklyaev. – Moscow: “Bylina”. 2000. – 555 с.
Peas and beans. Crop production science in horticulture / Antony J. Biddle. 2017. UK.
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.