Lentils are a food, fodder and technical leguminous crop.
Source: commons.wikimedia.org©Victor M. Vicente Selvas (CC0 1.0)
Economic importance
Lentil grains are used in the food industry to make protein preparations, sausages, canned foods, confectionery products (some kinds of chocolate, candy, cookies). The seeds are noted for their high taste qualities. They are used as fresh or canned food. Seeds have a 24-30% protein content; they surpass peas, chickpeas and beans in digestibility, 1.4% fat content, 52% carbohydrate content, and 3.2% mineral content.
For food purposes the large-seeded forms of lentils are primarily used, while the small-seeded ones are used for fodder purposes.
Lentil straw and hay are used as fodder. The protein content of the straw is about 14 to 15 percent and corresponds in nutritional value to good meadow hay, while the chaff contains up to 18 to 20 percent, which is superior to oats and rye bran. 1 kg of lentil chaff contains 0.56 fodder units. Ground lentils are also used as forage and are a good concentrated feed for all farm livestock.
History of the crop
Lentils are one of the oldest cultivated plants, introduced into crops more than 4,000 years ago. It was widely used for food purposes in ancient Egypt, India, the Arab states, and was known as a cultivated plant in ancient Rome and Greece.
P.M. Zhukovsky believes that cultivated lentils come from the Himalayan and Hindu Kush regions. Also the place of origin is called large-seeded – the Mediterranean, small-seeded – Iran and Afghanistan.
Lentils have been known to Russia since the 14th century.
Cultivation areas
The total global area of lentil cultivation is about 3.4 million ha, or 2.1 per cent of the leguminous crops. The gross seed yield is 2.9 million tonnes or 1.3% of the total legume yield at an average yield of 0.8 t/ha.
Large-seeded forms are cultivated in Europe, Asia, Africa and Latin America. Egypt, Spain, Romania, the Czech Republic, Slovakia and Chile are considered to be large producers. Small-seeded forms are distributed in Southwest and Central Asia.
In the USSR it occupied about 15 thousand hectares. In Russia, there are no official statistics on lentil production. It is estimated that the area sown is 10-15 thousand ha or 1% of the leguminous crop, the gross yield is 15 thousand tons (0.8%) with an average yield of 1.3 t/ha.
In Russia, the main cultivation regions are the Volga region (90% of the area sown) and the Central Black Earth zone (9%). Small areas of cultivation are in Tatarstan, Chuvashia, Mordovia and Western Siberia, as well as in Ukraine and Kazakhstan.
Yields
The average lentil seed yield is approximately 1.3 t/ha. Under favorable conditions, yields are 2.0-2.5 t/ha.
The highest seed yields were obtained in Kirovograd region (Ukraine) at the Ulyanovsk state variety plot, where they reached 3.4 t/ha.
Botanical description
Lentils are annual, relatively low growing plants.
Its root is taprooted.
The stem is slender, tetrahedral, warty, branched, prone to lodging.
Leaves are pairs-petioled, ending in tendrils.
Flowers are small, white or bluish. Are planted singly or by 1-4 in leaf axils. Self-pollination predominates.
Beans are short, flat, rhombic, contain 1-3 seeds, tend to crack at maturity, fall off when plants are overripe.
Seeds are lenticular, 3 to 9 mm in size.
Commodity quality requirements:
- proportion of seeds 6 mm in diameter should be at least 95%;
- homogeneity of the green color, without mottling and dark borders;
- consistency in color and size; no impurities are allowed.
Varieties
Cultured lentils (Ervum Lens L. Lens esculenta Moench) are subdivided into:
- coarse-seeded, or plate-seeded;
- small-seeded.
Large-seeded lentils (ssp. macrosperma Vag.) are larger plants up to 40-70 cm in height, with oval leaves, large beans and large, flat green, spotted seeds 6-9 mm in size and yellow seedpods. The growing season is 80-120 days. The weight of 1,000 seeds is 55-65 g.
Small-seeded lentils (ssp. microsperma) are characterized by their smaller plants, up to 15-50 cm, with small, elongated leaves, small beans, small, convex seeds 2-6 mm in size, of various colors, and orange seedpods. Vegetation period 65-70 days, more drought-resistant. Weight of 1000 seeds 25-30 g.
Biological features
Temperature requirements
Lentils are a more heat-loving crop than peas. Seeds begin to germinate at 4-5 °C, sprouts are damaged by frosts of -5 … -6 °C, but they nevertheless endure them. They can easily survive frosts of -2 … -3 °C.
The optimal daily average temperature after sprouting is 17-19 °C, and during the ripening period, 19-20 °C.
Moisture requirements
Lentils are less demanding to moisture (but are also moisture-loving). They grow well in dry regions.
During ripening and seed ripening excessive moisture is undesirable, as plants begin to increase green mass to the detriment of bean formation.
Light requirements
Lentils – a culture of long daylight hours.
Soil requirements
Loose light loamy and sandy loamy, lime-rich soils are optimal.
Acidic, compacted, heavy, very light, poor sandy, overwatered, waterlogged or saline soils are poor.
Vegetation
Vegetation phases:
- sprouting;
- flowering;
- bean forming;
- ripening.
Lentils grow slowly at the beginning of vegetation, accelerating with the beginning of the flowering phase. Acceleration of growth is associated with strong branching of plants. When the soil is moist and warm, sprouts appear in 8 to 12 days.
Because of the small height of plants and slow growth in the initial period of vegetation, it is especially sensitive to weeds in the fields.
Flowering occurs 40-45 days after sprouting. The flowering phase is delayed under rainy and cloudy weather, which leads to uneven bean ripening. Ripening begins with the lower beans, especially in wet years.
Crop rotation
Main article: Leguminous crops of the crop rotation
In a crop rotation, lentils are usually placed after fertilized winter cereals, buckwheat, potatoes, sunflowers, corn and sugar beets.
Like other leguminous crops does not tolerate repeated sowing, return to the same place in the rotation no earlier than 5-6 years, since it is damaged by nematodes.
Lentils are good for many crops in crop rotations, especially for spring cereals and corn, but are less suitable for winter crops than peas with the exception of early maturing varieties.
Fertilizer system
Large doses of mineral and organic fertilizers can result in excessive aboveground growth to the detriment of bean yields and uneven ripening. For this reason, it is not recommended to apply manure and other organic fertilizers under it. Organic fertilizers are applied under the predecessor or two years before its sowing.
Nitrogen fertilizers can be applied only for plant nutrition at the beginning of growth and development before the formation of nodules on the roots.
Acidic soils are limed by applying lime fertilizer under cultivation.
Under autumn plowing phosphorus-potassium fertilizer P40-60K30-40 is applied. It is effective to apply phosphorus fertilizer in rows during sowing.
Tillage
Tillage is similar to that for peas and other early crops.
Weed control is of great importance. This is achieved by early discing of stubble, deep autumn plowing, where possible – semi-fallow tillage.
Sowing
Seed preparation
We recommend treatment of seeds before sowing with bacterial preparations nitragin or risotorfin, which increases the yield by an average of 0.3 t/ha.
The use of sorted seeds of high quality of regionalized varieties is of great importance in obtaining high yields.
When sorting the seeds pay attention to the separation of the seeds of flat-seeded vetch.
Sowing dates
Lentils are sown at the same time as early grains or 5-7 days after sowing of early grains. Early sowing increases crop resistance to pests and diseases.
Sowing methods
Sowing method is row (15 cm) and narrow-row (7.5 cm).
According to the data of the South-East Research Institute of Agriculture (Saratov), the usual row sowing resulted in 1.38 t/ha yield of lentils seeds, the narrow-row sowing – 1.52 t/ha.
Seeding rates
Rates for large-seeded varieties – 2-2.6 million/ha of germinated seeds or 120-150 kg/ha, small-seeded – 2.5-3 million/ha or 80-100 kg/ha.
Seeding rates are adjusted depending on soil and climatic and local conditions. When the narrow-row method of sowing, the seeding rate is increased by 10-15%.
Sowing depth
Sowing depth of lentils is 4-6 cm.
On light soils and in dry conditions the depth is increased to 7-8 cm, on heavy and dense soils it is reduced to 3-4 cm.
Crop care
For uniform and more rapid emergence of seedlings, post-sowing rolling with the use of ring-spiked rollers is carried out.
A specific weed of lentil crops is the flat-seeded vetch. It strongly deteriorates the food and taste qualities of lentils. If this weed clogs crops, carry out manual weeding 3-4 weeks after sowing and during the flowering phase of vetch, when it produces red-violet flowers (these very flowers help easily distinguish the weed from the lentils).
Harvesting
For harvesting high-stemmed lentil varieties and weedy crops use a two-phase method. Mowing in swaths begins when about 50% of the beans are ripe. A slight delay in harvesting is associated with the loss of the lower, most valuable beans and the browning of the seeds, then the valuable seeds are greenish in color. Lentils dry out quickly, and threshing begins after 1 to 2 days. Delayed threshing also leads to seed discoloration and loss of merchantability.
The one-phase method is used for harvesting low-growing varieties of lentils. Harvesting begins when 85-90% of the beans are ripe.
In both methods, harvesting is carried out on a low cut in a short time. If the windrows get wet during drying, there is a sharp drop in seed quality, so the single-phase harvesting method is preferable.
Sources
V.V. Kolomeychenko. Horticulture/Textbook. – Moscow: Agrobiznesentr, 2007. – 600 с. ISBN 978-5-902792-11-6.
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.