🌾 Peas and Other Rabi Pulses

Rabi pulse crops improve both farm profitability and soil health when integrated thoughtfully into cropping systems. This lesson covers field pea and related pulses with management and system-level fertility benefits.

Field Pea (Pisum sativum)

Taxonomy and Types

Field pea (Pisum sativum var. arvense) belongs to the family Fabaceae. It is distinct from the garden/vegetable pea (P. sativum var. sativum) though both are the same species:

Economic importance:

• Protein content: ~24%; widely consumed as dal (split peas) and whole grain
• Dual purpose: Green pods as vegetable (fresh sale, high value); dry grain for dal
• Grown in cooler regions (UP, Bihar, HP, J&K, Punjab, Uttarakhand)
• Important rotation crop after paddy in eastern and hill regions

Climate and Soil Requirements

• Temperature: 10–22°C optimum; intolerant of high temperatures at flowering
• Frost tolerance: Moderate — young plants tolerate -4°C; frost at flowering causes major damage
• Soil: Sandy loam to clay loam; pH 6.0–7.5; well-drained soils essential
• Altitude: Can be grown up to 2,500 m in Himalayan foothills

Important Varieties

Powdery mildew resistant varieties are critically important because powdery mildew (Erysiphe pisi) is the most damaging disease of field pea in India — late sowing and humid conditions promote severe incidence.

Agronomy

Key Diseases and IPM

• Powdery mildew (Erysiphe pisi): White powdery coating on leaves; spray Karathane (dinocap) or Wettable Sulphur; grow resistant varieties (KPMR-400)
• Wilt (Fusarium oxysporum): Use tolerant varieties; Trichoderma seed treatment
• Rust (Uromyces fabae): Spray Mancozeb at appearance

Yield

• Field pea yield: 1.0–1.8 t/ha dry grain
• Green pod yield: 6–8 t/ha (for vegetable purpose)

Chickpea — Overview for Rabi Context

(Full crop agronomy covered in dedicated chickpea module; key points for Rabi context below)

Chickpea (Cicer arietinum L.) is the most important Rabi pulse in India (~9 MT production). Grown in Madhya Pradesh, Maharashtra, Rajasthan, Karnataka, and Andhra Pradesh.

Key agronomic points in Rabi season management:

Seed treatment: Triple treatment recommended:

1. Trichoderma viride (5 g/kg) — against Fusarium wilt and dry root rot
2. Rhizobium ciceri (200 g/10 kg seed) — BNF
3. Thiram + Carbendazim (2.5 g/kg) — seed-borne pathogens

Spacing: 30 cm × 10 cm; seed rate 60–80 kg/ha

Wilt management (Fusarium oxysporum f. sp. ciceris): Most serious disease; long rotation (3 years without chickpea on wilt-infested soil); grow wilt-tolerant varieties (JG-74, KAK-2); avoid heavy clay soils

Pod borer (Helicoverpa armigera): Spray Spinosad 45 SC (0.01%) or HaNPV at 250 LE/ha; economic threshold 1 larva/plant

Lathyrus (Grass Pea / Khesari Dal)

Lathyrus sativus is a drought-hardy Rabi pulse grown extensively in Bihar, UP, MP, and West Bengal under marginal and rainfed conditions.

Importance and Controversy

Advantages:

• Grows on waterlogged, marginal soils where other pulses fail
• Extremely drought-tolerant once established
• Nitrogen-fixing legume; improves soil fertility
• Cheap protein source (25–28% protein) for rural poor

Neurolathyrism concern:

• Seeds contain BOAA (β-oxalyl-L-α,β-diaminopropionic acid) — a neurotoxin
• Prolonged exclusive consumption (>300 g/day) causes lathyrism — irreversible spastic paraplegia (leg paralysis)
• Declared illegal for human consumption in several states, yet still consumed in food-insecure regions
• Safe doses: <300 g/day; traditional processing (boiling, soaking, roasting) reduces BOAA content

Agronomic Summary

Rabi Pulse Intercropping Systems

Intercropping of pulses with cereal or oilseed crops is a traditional practice in Bihar, UP, and MP for risk management and resource optimization.

Important Intercrop Combinations

Land Equivalent Ratio (LER): Most Rabi pulse intercrops show LER of 1.2–1.6, meaning 20–60% more land would be needed to produce the same total output from sole crops.

Soil Fertility Benefits of Rabi Pulses

Rabi pulses provide critical ecosystem services that sustain the long-term productivity of cropping systems:

1. Biological Nitrogen Fixation (BNF)

The fixed nitrogen is partially released to the subsequent crop through:

• Root exudates during crop growth
• Decomposition of nodules and residues after harvest

2. Improvement of Soil Physical Properties

• Root penetration: Deep tap roots of chickpea and pea break sub-soil compaction
• Soil structure: Legume residues improve aggregate stability and porosity
• Organic matter: Incorporating pulse residues (stems, leaves, roots) adds organic carbon

3. Breaking Pathogen and Weed Cycles

• Non-cereal break crop: Interrupts build-up of cereal-specific pathogens (wheat take-all, crown rot)
• Different weed competition: Pulses suppress different weed species than wheat; reduces problem weed populations
• Allelopathy: Some pulse residues suppress germination of certain weeds

4. Rhizosphere Effects

• Organic acid secretion by pulse roots solubilizes phosphates from sparingly soluble forms
• Increases availability of P and micronutrients (Fe, Zn) for subsequent crops
• Supports diverse soil microbial communities

Economic Benefit of Including Pulses in Rabi Rotation

• Saves 30–50 kg N fertilizer/ha for the next crop through residual N
• Diversifies income — pulse prices often higher than wheat per quintal
• Reduces input cost — low water and fertilizer requirement
• MSP support: Government provides Minimum Support Price for chickpea (₹5,440/q), lentil (₹6,000/q), and pea (₹3,400/q) in 2023–24, providing income security

Summary Cheat Sheet