Modern Lentil Farming: BARI Masur Varieties, Sowing, Fertiliser and Disease Control

In most of Bangladesh the winter crops go in only after the transplanted aman rice has been cut. Often, by the time the paddy is off the field, the soil has dried out, or it never reaches the workable "jo" condition at all, and the lentils cannot be sown on time. The Bangladesh Agricultural Research Institute (BARI) describes exactly this problem in its farm technology handbook.

People once said Bengalis lived on fish and rice; today it is dal and rice, and lentil (masur) dal is the favourite. BARI calls lentil the most popular pulse crop in the country.

This guide sets out the BARI Masur varieties, the soil and sowing window, seed and fertiliser rates, the main diseases and pests with BARI's controls, three ways to fit lentil into rice land, and harvest and storage. All rates are given as BARI's Krishi Projukti Hatboi (farm technology handbook, ninth edition) states them.

The handbook, quoting Krishi Diary 2019, puts lentil's national area at about 1.891 lakh hectares and its output at about 2.382 lakh metric tonnes, with an average yield of 1,260 kg per hectare. Among pulses, it says, lentil comes first in use and popularity.

Pulses as a group covered about 8.198 lakh hectares and produced about 10.386 lakh metric tonnes in the same figures. BARI notes that a Food and Agriculture Organization report recommends 45 grams of pulses per person a day, while Bangladeshis eat on average only 17 grams.

BARI's handbook calls pulses one of the main sources of plant protein in the country, with 20 to 35 per cent protein depending on the crop. Banglapedia, the national encyclopedia, gives whole lentil seed as 25 per cent protein, 55.8 per cent carbohydrate, 1 per cent fat, 3.7 per cent fibre and 3.3 per cent ash, with 11.2 per cent water.

Pulses are grown widely in the south, north and west: Barishal, Patuakhali, Barguna, Bhola, Jashore, Magura, Faridpur, Rajbari, Jhenaidah, Chuadanga, Meherpur, Kushtia, Pabna, Sirajganj, Natore, Rajshahi and Chapainawabganj, according to the handbook. The loam to clay-loam soils there are high or medium-high and free of floods, so farmers can plant aman on time and follow it with a pulse.

Lentil (Lens culinaris) belongs to the legume family. Banglapedia describes a winter plant 25 to 40 cm tall with slender stems, pinnate leaves and small flat pods holding one or two lens-shaped seeds. It tolerates some drought but suffers badly in waterlogged soil, and BARI adds that a lentil crop improves the fertility of the field.

BARI's Pulses Research Centre breeds lentils by selecting from collected germplasm and by crossing, and it tests lines received from the International Center for Agricultural Research in the Dry Areas (ICARDA) in Bangladeshi soil and weather. The handbook lists nine high-yielding, disease-tolerant and nutrient-rich varieties released so far.

• BARI Masur-1 (Utfala): developed from germplasm collected in the Pabna area and approved by the National Seed Board in 1991. Cooks in 10-12 minutes, 26-28 per cent protein, matures in 105-110 days, yields 1,700-1,800 kg per hectare.
• BARI Masur-2: a line brought from ICARDA in 1984 and released in 1993 after multi-location trials. Cooks in 14-16 minutes, 27-29 per cent protein, matures in 105-110 days, yields 1,500-1,700 kg per hectare.
• BARI Masur-3: a cross made in 1985 between a local variety and an advanced line, approved in 1996. Grey seed with small black spots, matures in 100-105 days, yields 1,500-1,700 kg per hectare.
• BARI Masur-4: a 1985 cross of BARI Masur-1 with an ICARDA line, released in 1996. Large flat reddish-brown seed, tolerant of rust and Stemphylium blight, yields 1,600-1,700 kg per hectare.
• BARI Masur-5: selected from a crossed population from ICARDA, Syria, and approved in 2006. Matures in 110-115 days, average yield 2,100-2,200 kg per hectare, tolerant of rust and Stemphylium blight.
• BARI Masur-6: from an ICARDA population brought in 2000 and approved in 2006, chosen for high yield, disease tolerance and high iron and zinc. Dark brown, very large flat seed, yields 2,200-2,300 kg per hectare in 110-115 days, tolerant of rust and Stemphylium blight.
• BARI Masur-7: from an ICARDA line, suited to all regions and especially productive in Pabna, Jashore, Kushtia, Faridpur, Rajshahi, Magura, Jhenaidah and Madaripur. Matures in 110-115 days, yields 1,800-2,300 kg per hectare.
• BARI Masur-8: a zinc- and iron-rich line developed at ICARDA, approved in 2015. Tolerant of Stemphylium blight, 24.0-24.9 per cent protein, matures in 110-115 days, yields 2,100-2,200 kg per hectare, and can be sown late, up to the last week of November.
• BARI Masur-9: from zinc- and iron-rich germplasm received from ICARDA in 2007, tested in four districts from 2012 to 2017 and approved in 2018. Matures in only 85-90 days, so it fits the fallow gap between aman and boro rice; tolerant of leaf blight.

When ICARDA announced BARI Masur-8 on 12 August 2015, it said the variety averaged 2,000-2,200 kg per hectare against about 1,050-1,100 kg for local varieties, and carried 72-75 ppm iron and 58-60 ppm zinc, against 55-62 ppm iron and 32-41 ppm zinc in local lentils. The BARI handbook gives its own measurements of 80 ppm iron and 60 ppm zinc.

BARI recommends well-drained loam, sandy loam or clay loam; it adds that BARI Masur-7 can even be relay-cropped on clay where water does not stand.

For a sole lentil crop on well-drained land with the right moisture, plough three to four times deeply and ladder until the soil is fine and loose. If the lentil is sown as a relay crop into standing aman rice before harvest, no ploughing is needed.

Time matters more than almost anything else. The handbook gives the best sowing time as the last week of October to the second week of November, which is the second week of Kartik to the end of Kartik. Research cited by BARI found yield falls by about 20 per cent for every 10 days that sowing is delayed. BARI Masur-8 can be sown up to the last week of November: the yield drops a little, but BARI says the risk of heavy disease losses is lower.

Treating seed before sowing protects pulses from many soil- and seed-borne germs, the handbook says. Its steps, in order:

• Treat the seed with Provax-200 WP, a fungicide combining carboxin and thiram, at 2.5 g per kg of seed. BARI says this reduces foot rot in the early stage.
• On land where lentil has never been grown, mix approved microbial (rhizobium) fertiliser with the seed at 50 g per kg of seed before sowing.
• Sow by broadcasting or in lines. Line sowing gives even growth and makes weeding, disease and pest control, irrigation, drainage and harvesting easier; BARI suggests 25 cm between rows.
• Use 30-35 kg of seed per hectare, a little more if broadcasting. BARI Masur-3 needs 35-40 kg, a relay crop in aman rice needs 50-60 kg, and BARI Masur-9 needs 70-75 kg per hectare.

Where seed is inoculated with microbial fertiliser, the handbook says urea is generally not needed. For a sole crop on infertile land, BARI recommends applying all of the following at the final ploughing, per hectare (per bigha in brackets, as BARI gives it):

• Urea: 40-45 kg (5-6 kg)
• TSP: 80-90 kg (11-13 kg)
• MoP: 40-45 kg (5-6 kg)
• Gypsum: 50-55 kg (7-8 kg)
• Boron, if needed: 7-10 kg (1-1.5 kg)
• Microbial fertiliser, if needed: as recommended

For BARI Masur-6, 7 and 8, BARI warns against adding organic or nitrogen fertiliser on naturally fertile land, because a dense, lush canopy favours rust.

Lentil is usually a rain-fed crop. If weeds appear, BARI advises one weeding within 25-30 days of sowing. Because lentil cannot tolerate waterlogging, open drains after heavy rain. If growth slows for lack of soil moisture, give one light irrigation 30-40 days after germination and loosen the soil afterwards.

BARI names five problems farmers should watch for. Doses are the handbook's; read the label and ask the upazila agriculture office before spraying.

BARI calls Stemphylium blight the most damaging lentil disease in Bangladesh today. It was first identified in 1986 and has since spread across the west and south-west, including Dhaka district, and is now seen throughout the country. The cause is the fungus Stemphylium botryosum, carried by the wind and surviving in crop residue; research cited by BARI shows it can cut yield by up to 80 per cent.

Pinhead-sized light-brown spots appear on the leaves and within three to four days whole leaves are affected and fall; a badly hit field looks scorched.

BARI's pathologists found that spraying Rovral 50 WP or Folicur 250 EC, or a mix of the two, at 0.2 per cent in water three or four times at 7-day intervals, on a bright morning between 9 and 10 am, protects the crop. BARI Masur-8 has resistance to this disease.

Foot rot, caused by the soil fungus Sclerotium rolfsii, mainly attacks seedlings up to about a month old. Young seedlings suddenly wilt, dry to the colour of straw and disappear; on older seedlings white thread-like fungal growth and mustard-seed-like sclerotia appear at the base.

The disease is worst where the soil is wetter than "jo" condition at sowing, so avoid sowing in excess moisture. Treat seed with Provax-200 WP at 2.5-3.0 g per kg. BARI's integrated management page also advises burning crop residue, sunning the ploughed soil for five days, and applying partly rotted poultry manure at 5 tonnes per hectare at least 21 days before sowing, or Trichoderma-based tricho-compost at 3 tonnes per hectare at the final ploughing. Drenching the base of the plants with Provax at 0.25 per cent 20-25 days and again 35-40 days after germination controlled the disease and raised yield by 28-43 per cent, BARI reports. If it still persists, change the crop rotation next year.

Rust is caused by the fungus Uromyces fabae. A dense canopy with 85-90 per cent humidity inside and air temperatures of 20-22 degrees Celsius suits it. Yellow or rust-coloured blisters appear on leaves, stems and pods and later turn dark brown or black; leaves drop and plants dry before maturing, so the field looks grey from a distance. In the south it usually begins before the end of January, in the north in the first half of February.

BARI Masur-6, BARI Masur-7 and BARI Masur-8 resist rust. Sowing in the last week of October in the south and the first week of November in the north helps the crop escape it. When the disease appears, spray Tilt-250 EC at 5 ml per 10 litres of water two or three times at 7-10 day intervals.

Wilt, caused by Fusarium oxysporum f. sp. lentis, was first identified in Bangladesh in 1977 at the Bangladesh Agricultural University farm in Mymensingh. Seedlings stop growing and yellow from the bottom up; a split root shows dark brown streaks.

BARI advises treating dry seed with Autostin and thiram mixed 1:1 at 0.25 per cent, sowing on time, avoiding over-wet soil at sowing and, when the disease appears, spraying Autostin at 2 g per litre two or three times at 7-10 day intervals. If it returns, change the crop rotation.

Aphids suck sap from leaves, stems, flower clusters and pods, and a heavy attack stunts the plants and cuts yield. For a severe attack the handbook advises a dimethoate insecticide (such as Tafgor 40 EC) at 2 ml per litre of water.

Because so much lentil follows aman rice, BARI describes three methods for getting the crop in on time.

In relay cropping the lentil seed is broadcast into the aman field 10-15 days before the rice is cut, as the water recedes, straight into the mud. BARI says this costs 45 per cent less than sowing after tillage. It suits loam and clay-loam fields that do not reach "jo" in the sowing window.

• Soak the seed for 8-10 hours before sowing, and use 50-60 kg per hectare.
• One or two days before sowing, broadcast 90 kg TSP and 45 kg MoP per hectare; add 7-10 kg of boric acid or borax per hectare where boron is short.
• Where lentil is new to the field, mix 50 g of microbial fertiliser per kg of seed.
• Top-dress 40 kg urea per hectare 4-5 days after the rice harvest, in the afternoon if the soil is dry.
• Cut the rice 5-7 days after the lentil germinates, leaving 25 cm of straw. Hand-weed 30-35 days after sowing if needed.

BARI puts the yield of this method at 1,500-1,600 kg per hectare.

Where the soil dries quickly after the rice harvest, soak the seed in a bucket or basin overnight for 8-10 hours, dry only the surface water in the shade next morning and sow the same day. Primed seed germinates three to four days earlier and grows better, BARI says. Use 30-35 kg of seed per hectare, with 40 kg urea, 90 kg TSP and 45 kg MoP at the final ploughing, plus 7-10 kg boric acid or borax where boron is short. Broadcast after three or four ploughings, or sow in rows 25 cm apart.

For northern soils with pH 7 to 8, BARI describes a conservation agriculture method: half of the rice straw is left in the field and a two-wheel tractor tills strips, sows the seed and places the fertiliser in one pass during the first two weeks of November. The strips are 4-5 cm wide and 5-7 cm deep, with 20-30 cm between rows, so only about 20 per cent of the land is tilled. The handbook reports 16-18 per cent higher yield than usual practice and fewer weeds, aphids and leaf blight.

Lentil is ready 110-115 days after sowing, or 85-90 days for BARI Masur-9. Harvest when the plants and pods have turned brown; by the Bengali calendar this generally falls from mid-Falgun to mid-Chaitra, in March.

Cut the plants at the base, sun-dry them, thresh with sticks, cattle or a machine, then clean the seed and dry it for two to three more days.

For seed, the original guide advised drying until moisture is below about 10 per cent and storing it in tin containers, polythene or jute bags, or earthen pots coated with tar. BARI's handbook asks for airtight containers.

BARI's lentil varieties come from its Pulses Research Centre at Ishwardi in Pabna. For seed of a released variety, the right fungicide and the dose for local soil, farmers can go to the upazila agriculture office of the Department of Agricultural Extension.

Photo: Miwok / Wikimedia Commons (CC0)

Sources: The Agro News (Staff Correspondent), Bangladesh Agricultural Research Institute (Krishi Projukti Hatboi, ninth edition), International Center for Agricultural Research in the Dry Areas (ICARDA), Banglapedia