REDGRAM - Cajanus cajan L. Millsp. ( 2n = 22)Syn: Cajanus indicus Spreng

Vernacular names

Redgram,pigeonpea, Congo bean, Angola pea, Thovarai (Tamil), Arhar (Hindi), Tur (Hindi) and Kandulu (Telegu)

IMPORTANCE

Redgram is the second most important legume of India

Redgram are consumed as fresh green peas in Caribbean, Latin American, Puerto Rico, Trinidad, India, Kenya, Tanzania and Zambia

In India, late maturity types of vegetable redgram are grown in kitchen backyards or as bund crop

The top of the plants with fruit provide excellent fodder and are also made into hay and silage

Redgram is used as shade crop in cacao and turmeric as wind breaks and for antierosion works

The dried and stalks are used for firewood, thatching and baskets

Redgram Origin

Primary centre - Africa Secondary centre - India

Distribution

World: USA, Hawai, West Indies, India, Australia, Kenya, Uganda, Tanzania, Namibia, Malawi

India: Uttar Pradesh, Bihar, Madhya Pradesh, Maharastra, Andhra Pradesh, Tamil Nadu

BOTANY

Redgram is an annual

Plant height is 0.6 to 1.5 m in height

Deep tap root system

Leaves are trifoliate and spirally arranged

Leaflets are banceolate to narrow elliptic, hairy on both sides

Inflorescences is raceme

Pod has 3 to 4 seeds

Hundred seeds weight 11 to 13 gm

Redgram is self pollinated

20 % cross pollination due to bees and other insects

Flowers open between 11 a.m. to 3 p.m. and remain open for 6 hours

Podding begins in 12 to 14 weeks after sowing

Pods in early varieties require 5 to 6 months to reach maturity

Pods in late varieties require around 9 months to reach maturity

Conversion ratio from fresh green pods to dried pods is about 3.3

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Two ecotypes in redgram

(i) Cajanus cajan var. flavus are Tur cultivars

Earlier maturing cultivarsShorter plants green glabrous podspods are light coloured when ripe Pod are three seeded Tur cultivars are cultivated in Peninsular India

(ii) Cajanus cajan var bicolor are Arhar cultivars

Perennial cultivarsLate maturing cultivars Large, bushy plantsPods are hairy blocked with maroon or dark colourPod has 4 - 5 seeds Arhar cultivars are grown in north India.

Chemical composition of RedgramFeature Green seed

(%)Dry seed

(%)Dry ripe seed (%)

Split seed (dhal (%))

Moisture 67.4 10.0 10.1 15.2Protein 7.02 1.31 9.2 22.3Fat 0.6 2.1 1.5 1.7Carbohydrate

20.2 --- 57.3 57.2

Fibre 3.5 --- 8.1 ---Ash 1.3 --- 3.8 3.6

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CLIMATE

Redgram is cultivated between 30oN and 30oS up to an altitude of 1800 m from MSL

Redgram is less suitable for wet tropics

Redgram is short day plant. Late maturity varieties are short day plants while early

varieties are photosensitive plants.

The cardinal minimum, optimum and maximum temperature is 10o C, 24oC to 29oC and 35oC respectively

Redgram is susceptible to frost damage at all stages of growth.

Average annual rainfall of 600 mm to 1000 mm is most suitable for redgram growth and yield.

Rainfall of 625 mm per year is adequate for good growth under semiarid conditions

High yields are obtained when there is good rainfall during the first 2 months of growth followed by a dry period during flowering and harvesting.

It is a drought resistant crop with deep root system.

Redgram is fairly resistant to wind and is sometimes planted in double rows as a wind break.

SOIL

Redgram can be grown on almost all soil types Soil should not markedly be deficient in lime It thrives best on deep loam soils free from excessive

soluble salts and near neutral pH

It is sensitive to sea spray and does not thrive near the seashore

It will not tolerate waterlogging condition Redgram is sensitive to salinity and alkalinity

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LAND PREPARATION

Subsoiling on lands having hardpan permits both deep proliferation of roots and great infiltration of water to the deeper layers of the soil

Seedbed moisture content of 40 to 50 % to ensure quick and adequate germination

Surface drainage is an important in the seed bed preparation

SEASON

Kharif (June-August) Puratasipattam (September-November) Summer (February-March)

Growth stages

Type Days to % flowering

Days to 75 % flowering

Days to maturity

Long duration 100 107 180Short duration 83 93 135

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SEED RATE AND VARIETY PARTICULARS OF REDGRAM

Varieties

Seed rate (kg per ha) Duration (days) Hundred

seed weight (gm)

Seed yield kg per ha

Pure crop

Mixed crop

50 % flowerin

gMaturity Rainfed Irrigated

SA 1 10 5.0 120-130 180 8.5 1250 -CO 3 25 12.5 90-95 130 7.2 1180 1400

CO 4 25 12.5 90-95 130 8.5 980 1750

CO 5 25 12.5 70-75 110 8.0 760 -CO 6 10 9.0 120-130 180 8.8 900 -

Vamban 1 25 12.5 70 100 8.8 840 1200

BSR 1 - - 100-110 180 12.0 1.0kg /plant -

Note: SA 1, CO 3, CO 4 and BSR 1 are used for bund planting @ 50 gm per 100 m.

Spacing for pure crop, intercrop / bund crop

Variety Spacing for pure crop spacing for intercrop / bund crop

Co2 45 cm x 30 cm ----Co 3 45 cm x 30 cm ----Co 4 45 cm x 30 cm ----Co 5 45 cm x 30 cm ----Co 6 90 cm x 30 cm 240 cm x 30 cmSA 1 90 cm x 30 cm 240 cm x 30 cmBSR 1, SA 1 ---- 60 cm

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SEEDS AND SOWING IN REDGRAM

Seeds are sown either by broadcasting, line sowing or dibbling Treat the seeds with carbendazim or Thiram @ 2 g/kg of seed Fungicide treated seeds should be again treated with a rhizobium

culture

24 hours interval for giving rhizobium culture treatment after fungicidal treatment

Three packets of rhizobial culture (600 g) for treating 25 kg of seeds for one ha

Culture slurry is prepared with 500 ml of rice gruel + 10 % of sugar / gur / jaggery solution

50 gm of sugar or gur to 500 ml of waterBoil the solution for 15 minutes to dissolve the sugar in water Cool the stickys solution to room temperature

Mix three packets of rhizobial culture into the cooled sticky solution

Slurry solution helps rhizobium stick to the seed surface and also enhances the survival of rhizobium

Dry the bacterial culture treated seeds in shade for 15 minutes before sowing

The innoculated seeds should not be exposed to sunlight Seeds after innoculation with rhizobium should be sown as soon as

possible preferably on the same day

Innoculated sown seed should be covered with soil The innoculated seeds should not be allowed to come in direct

contact with chemical fertilizers. In very acid soils, it is advisable to sow the innoculated seeds along with lime, dolomite or neutralized super phosphate

Sowing of redgram can be done on ridges when soil internal

drainage is poor which leads to waterlogging

Seeds take nearly five days for germination under favourable conditions

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WEED MANAGEMENT IN REDGRAM

Critical weed free period is 60 DAS

Spray Fluchloralin 1.5 lit per ha or Pendimethalin 2 lit per ha mixed with 900 litres of water on three days after sowing which is followed by irrigation

Subsequently one hand weeding may be given on 30 to 35 days after sowing

If herbicide is not applied, give two hand weeding are given on 20 and 35 days after sowing

MANURES AND FERTILIZER APPLICATION

Basal application of 12.5-25-0 and 25-50-0 kg of N, P2O5 and K2O per ha is recommended for rainfed and irrigated conditions respectively.

Soil application of 25 kg of sulphur as gypsum (110 kg / ha) or 2 % urea in two sprays at flower commencement and 15 days after may be given.

GROWTH REGULATORS

Spray 40 ppm NAA (40 mg/litre) is mixed with urea at flowering initiation

Spray of TIBA @ 150 ppm (150 mg/litre) at flowering initiation to increase grain yield

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WATER MANAGEMENT IN REDGRAM

Water requirement is 400 mm It is a drought tolerant crop It responds well to irrigation during summer

seasons

Irrigate the crop immediately after sowing third day after sowing, bud initiation, 50 % flowering and pod development stages

Irrigation is given at 60 % depletion of available soil moisture

Water stagnation should be avoided

Ridge planting ensures quick disposal of rain water allowing no stagnation

Redgram is grown as rainfed crop

The moisture stored in the soil profile during monsoon (rainy) period is used by the crop in the post-monsoon period

CROPPING SYSTEMS

Redgram is grown either as sole crop or as an intercrop with cereals like sorghum, pearl millet or oilseeds like groundnut.

Mixed cropping with long duration varieties under rainfed conditions

Intercropping of redgram + groundnut in 1 : 6 ratio is recommended for during kharif season.

Multitier cropping of redgram for rainfed black soil with more than 300 mm rainfall during the cropping period

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agathi with 1 m x 1 m spacing forms first tier, redgram with 45 cm x 20 cm forms second tier, cotton with 45 cm x 20 cm forms third tier and blackgram with 30 cm x 10 cm forms fourth tier

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HARVEST Pods are picked as they mature, when most of

leaves have dried and shed

Whole crop is cut down when about two-thirds or three quarters of the pods are mature

Plants are cut down to the ground level, tied into bundles, and left to dry for a few days, before being threshed

Pods and left after thrashing are usually beaten with sticks

Seeds and chaffs separated by winnowing

POST HARVEST TECHNOLOGY

Seeds moisture content at storage is 10 %

Periodic fumigation of the storage chamber with carbon bisulphide, phosphine, ethylene dibromide or methyl bromide is to be done against insect infestation

The ripe dry seeds are boiled and eaten as pulse

Ripe dry seeds are split and made into dhal through dry or wet method

Dry method: Dry seeds are placed in the sun for 3 to 4 days and are then split in a mill Reprat this process is repeated for 3 to 4 times

Wet method:Seeds are soaked in water for 6 to 10 times mixed with red earth overnight, than dried in the sun, after which the red earth is removed by sievingSeeds are finally split into dhal in a hand mill

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Split dhal is then treated with castor or sesame oil to improve its quality, give it an attractive appearance and prevent insect attack

Dhal yield is about 66 % by the dry method and 80 % by the wet method

PULSE CROPS AND THEIR IMPORTANCE

The word 'Legume' comes from Latin word 'Legere' meaning ' to gather ' and indicate that the seeds were collected by hand instead of being threshed from the plant as in cereal grains Grain legumes belong to the family Fabaceae

Grain legumes are leguminous species which includes the edible pulse grains and high protein leguminous oilseeds such as soybean and peanut.

Pulse is defined as the split cotyledons of dry legume seed which are used as food, boiled in water, softened, macerated and used as soup

Pulse applies to pigeonpea, chickpea, greengram, blackgram, lathyrus,and lentil

Pulses supply proteins which form the chief source in vegetarian food

Presently all legumes are used as dried, fried or boiled, powdered or macerated into soup.

All rabi pulses have a chromosome number of 2n = 14 except chickpea which has 16 whereas kharif pulses posses 2n = 22 except horsegram and field bean which have 24.

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IMPORTANCE OF PULSE CROPS

Indian people are mostly vegetarian, depending largely on cereals and pulses as their staple food

Pulses provide the main source of dietary proteins and calories

Average per capita consumption of pulse in India is about one ounce while the minimum requirement is about three ounces according to nutrition experts India is the major pulse growing country of the world accounting roughly for one third of the total world area under pulses and one fourth of the world production pulse

In the tropics, cereals on average account for about 68 % of total plant protein consumption; legume seed accounts 18.5 %, tubers, nuts, fruit and vegetables accounts 13.5 %. The protein content of grain legumes varies from 17 to 40 %.

Pulses contain 20 to 30 % protein, 60 % carbohydrates, 1.0 to 2.5 % fat and a good sources of thiamine, nicotinic acid, calcium and iron

Pulse proteins are rich in lysine and show deficiency of tryptophan and sulphur containing amino acids like methionine and cystine, a reverse situation exists in the cereals proteins.

Protein provided by cereals and pulse mixture is equivalent to skimmed milk in terms of its biological value.

Pulses mixed with cereals in 3:7 proportions enhance the overall nutritive value of proteins

The major form of phosphorus fraction in pulses is phytin phosphorus, which accounts for 40 to 50 % of total phosphorus.

Pulses are a good source of vitamins.

Germinated seeds of pulses contained increased amounts of carotene, ascorbic acid, pantothenic, biotin, nicotinic acid, thiamine, riboflavin and vitamin B12.

The digestibility coefficient, biological value and protein efficiency ratio varied from 60 to 90 percent, 45 to 78 percent and 0.7 to 1.1 respectively.

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Germination and cooking improve protein digestibility

Kabuli type of bengalgram has higher protein content than desi type.

Black gram is superior in its nutritive value among the pulse crops.

Blackgram and redgram are deficient in methionine, trytophan, threomine and lysine. The presence of saponins, glycosides, tanins, alkaloids with phytin in hemicellulose substance inhibit the action of digestive enzyme

Trypsin in different pulses adversely affect the pulses digestability.

Pulse crops or grain legumes play an important role for sustaining soil productivity as one of the component crop in various cropping systems.

Legume crops fix atmospheric nitrogen in symbiotic association with rhizobium which reduce the requirement of fertilizer nitrogen.

Quantity of nitrogen fixed by legume crops

Crops Nitrogen fixed (kg/ha)

Pigeon pea 41-91Greengram 61Cowpea 65-80Cluster bean 130Soybean 65Chickpea 103Groundnut 24Pea 50-80Lentil 35-75

Nitrogen harvest index values (seed nitrogen / total plant nitrogen) for cowpea, soybean, groundnut and chickpea is 0.61, 0.75, 0.80 and 0.73 respectively indicate the nitrogen economy of pulse or legume crops.

Pulse crops have deep penetrating top root system that helps to utilize the limited available soil moisture more efficiently than many other crops including cereals that contribute substantially to the loosening up of the soil.

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Pulses such as redgram, horsegram, mothbean, lathyrus and lentil are drought tolerant.

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REASONS FOR POOR YIELD OF PULSES

Grain legumes have either originated or being cultivated on marginal lands

Pulses have their deep root systems, nodulation and nitrogen fixation capacity These hardly enjoyed the inputs of irrigation and fertilization

Phaseolus, Vigna and Pisum are prostrate/ spreading / twining habitat which creates a tight leaf canopy that does not allow air exchange and is inefficient in utilizing sunlight growth and development are suppressed or delayed due to self shading

Vicia, Cicer and Cajanus have indeterminate growth habit

Flowers and pods abscise / abort for lack of nutrition

Flower shedding may be 30 to 50 %.

Pods do not develop to their full potential

Uneven maturity occurs in indeterminate cultivars

All the grain legumes have a high rate of photorespiration, typical of C3 plants.

C4 and CAM (Gassulacian Acid Metabolism ) are not found in the grain legumes.

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FACTORS LIMITING PULSE CROP PRODUCTION:

Ecological factors:

o 92 % area under pulse cultivation is rainfed condition

o Pulses are sensitive to excess moisture, waterlogging, acidity, salinity and alkalinity.

o Frost cause heavy damages to rabi pulses particularly to chickpea

o Continuous rain invites more insect pests and diseases both in kharif and rabi pulses.

Lack of proper agronomic management

Pulses crops can utilize the limited soil moisture and nutrients

Pulses are grown with poor management practices

Varietal features

Non availability of seeds of improved varieties,

indeterminate growth,

no response to good management,

flower and pod drop due to limitation of nutrients,

hormonal imbalance, etc.

Socioeconomic factors

Pulses have subsidary status as catch crops or intercrops

Limited resource is allocated for pulses production

Low economic return form pulse crops

Pulses are not remunerative

Pulses lack price policy in parity with cereals.

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ANTINUTRITIONAL AND TOXIC FACTORS

Raw pulses are of low nutritive value because of presence of trypsin inhibition, hemagglutinin, etc., which affect protein utilization

Pulses are known to contain toxic substances which are eliminated by soaking and subsequent discarding of the liquid and or by heat treatment at relatively elevated temperatures

Trypsin inhbitors inhibit proteolytic activity of certain enzymes

People consuming Lathyrus for prolong periods are known to suffer from paralytic disease known as lathyrism.

Phytohaemagglutinins substances possessing the property to agglutinate red blood cells

Lectins binds saccharides and saccharides containing proteins

Cyanogenetic glycosides releases hydrocyanic acid on hydrolysis of lima bean seeds

Favisum is characterised by hemolytic anemia affecting certain individuals following the ingestion of fresh raw or cooked broad beans

Saponins content in pulses cause abdominal pain, vomiting and diarrhea

Saponins reduce cholestrol level and the risk of heart disease

Saponins are not destroyed during cooking or processing. Fermentation reduces the level of saponins.

Tanins (Polyphenols) reduce the digestibility of dietary proteins

Removal of seed coats during processing will remove nearly all of the tannins

Panching and roasting of pulse seeds improved nutritive value of proteins and biological value

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