In this article we will discuss about:- 1. Origin and Distribution of Lentil 2. Climate, Soils and Tillage of Lentil 3. Varieties and Seasons 4. Seeding and Plant Population 5. Nutrient Management 6. Other Management Practices 7. Quality Considerations.
Origin and Distribution of Lentil:
Lentil (Lens culinaris) is the fourth most important pulse crop of the world after beans, pea and chickpea. Although, lentil is relatively minor crop on a world scale, it has local importance in certain regions.
This is particularly true in countries surrounding the Mediterranean, in the northern parts of India and in Latin America. In these regions, lentil is a valuable source of protein besides an important component of local or international trade.
The cultivated lentil is supposed to have originated in central Asia (India, Pakistan, USSR). Two types of lentils are known: Macrosperma (masur or malkamasur) with large flat pods and large seeds (6.9 mm dia) found in Mediterranean, Africa and central Asia and Microsperma (masuri) with small convex pods and small seed (3-6 mm dia), chiefly found in India, Pakistan and south and west Asia.
Lentils are grown in Egypt since prehistoric times from where it spread to southern Europe, west Asia, India and China. The major lentil producing countries are Turkey, India, Canada, USA, Syria, Morocco and Ethiopia. Globally, it is grown in about 2 M ha with a production around 2.5 M t. Highest yields are obtained in Egypt (2.2 t ha-1) followed by USA (1.0 t ha-1) and Canada (0.8 t ha-1).
India accounts for about 40 per cent of the global production. In India, as per 2008-09 statistics, it is cultivated in 1.31 M ha with a production of 0.81 M t accounting for a productivity of 622 kg ha-1. UP ranks first both in the area (0.51 M ha) and production (0.37 M t) followed by MP (area 0.48 M ha and production 0.21 M t). Productivity is highest (793 kg ha-1) in Bihar followed by WB (763 kg ha-1).
Climate, Soils and Tillage of Lentil:
Lentil is a cool season (rabi) pulse crop. It is not an economical crop in hot tropics. It is a long day plant. However, it has wide adaptability and can be cultivated from plains to an altitude of 3,500 m above sea level. Optimum temperature regime for growth and development is 15°-20°C.
It can tolerate cold. However, low temperatures less than 10°C delays germination with reduce vegetative growth. It can come up well on stored soil moisture in regions with annual rainfall of 350-500 mm.
Lentil can be cultivated on any soil from sandy loams to heavy black cotton soils, provided drainage is adequate. It can tolerate moderate acidity and alkalinity and can cum up on soils with pH between 4.5 and 8.2. The crop does not tolerate waterlogging. Lentil is relegated to marginal lands as it can establish well with minimum tillage. One ploughing followed by one or two harrowing is adequate for optimum seed germination.
Varieties and Seasons of Lentil:
Lentil resembles bengalgram a great deal in habit and cultivation. The duration of most varieties is 70-100 days. Lentil varieties recommended for different states have been given in Table 8.20.
Lentil, a cool season crop, requires temperature around 6°C for good germination. As such, optimum seeding time is from October first fortnight to November first fortnight. It is also grown as relay (pyra or utera) crop. The seed is broadcasted in standing rice crop a week before its harvest. Late sowings require a seed rate of 80 k ha-1 with a closer spacing of 20 x 5 cm. Optimum seeding depth is 4 to 5 cm.
Seeding and Plant Population of Lentil:
The seed is sown both by broadcasting and drilling in rows. Broadcasting is the only way for a relay crop of lentil in standing kharif rice. Optimum seed rate is 50 kg ha-1 for macrosperma (bold seed) when sown in optimum time with a spacing of 30 x 10 cm.
Late seeding requires higher seed rate of 80 kg ha-1 and closer spacing of 20 x 10 cm. Microsperma (small seed) when sown in time require a seed rate of 30 kg ha1 at a spacing of 30 x 5 cm. Late sowing require higher seed rate of 40 kg ha1 with a closer spacing of 20 x 5 cm. Deeper sowing than 4 to 5 cm is not ideal.
Nutrient Management of Lentil:
Lentil crop yielding about 2 t ha-1 removes around 100 N, 30 P2O5 and 80 K2O kg ha1. The crop is hardly fertilised. Results of experiments clearly indicated the need for fertiliser application for economic yield. A starter dose of 20 kg ha-1 is adequate to meet the needs of crop till nitrogen fixation is initiated. Depending of soil test, 40 P2O5 kg ha-1 appears to be optimum for most situations.
Usually the crop does not respond to potassium. However, based on soil test value, 20 K2O kg ha-1 meet the crop needs if the soil is deficient in potassium. Fertilisers should be applied by placement, 5 cm away from the seed at a depth of 8 to 10 cm at sowing. Drilling the fertiliser followed by drilling the seed appears to be the best method of application.
Single superphosphate, as source of phosphorus, can meet the needs of sulphur requirement of the crop. Lentil is highly susceptible to zinc deficiency especially if it follows rice. If zinc is not applied to rice crop, 25 kg ha-1 of Zn SO4 can meet the needs of lentil crop. Foliar application of 0.5 per cent Zn SO4 can correct the zinc deficiency in standing crop.
Other Management Practices for Lentil:
Lentil crop is usually grown during rabi on stored soil moisture. If it is seeded early in the season (November), there is no need for irrigation. Delayed seeding, especially on light soils is subjected to soil moisture stress at reproductive stage. Flower initiation and pod development stages are critical stages for water deficits. Two irrigations, one each at these critical stages are adequate for optimum yield.
Lentil crop is poor weed competitor due to slow initial growth. The first 45 to 60 DAS is the critical period of weed competition. Hand weeding at 30 and 60 DAS is the traditional practice. PRE herbicides such as Prometryn (1.0-1.5) and Pendimethalin (1.0 -1.5) can effectively control the weed in lentil crop. However, herbicides use is not economical under several situations due to low yields.
Pod borers and aphids cause considerable damage to lentil crop. Control measures are same as that indicated under bengalgram and greengram. Rust and wilt disease may cause considerable yield losses. Since, chemical control is not economical, growing resistant cultivars listed under varieties appears to be the ideal practice to minimise the losses under different situations.
Quality Considerations of Lentil:
Lentil seed contain protein 2.5 per cent, fat 1.5 per cent and carbohydrates 56.6 per cent. Calcium, iron and phosphorus contents (mg 100 g-1) are 130, 6.0 and 250 respectively. Lentil has high saponin content (3.7-1.6 g kg-1 seed), which reduces the cholesterol levels in the blood.
Lentils contain raffinose, which generate gas (flatulence). However, sprouting the seed can reduce its content to safer limits. Lentils are recommended for treatment of diabetics, as they are good source of dietary fibre.
Most of the lentils are consumed as dhal or in soups. Unripe pods are used as green vegetable, dry leaves and stalks as cattle feed. In Kashmir valley, it is grown as green manure crop for rice crop.