Pigeonpea (Arhar/Tur) Cultivation: Important Facts & One-Liners 🌱
📌 1. General Introduction & Botany
- Botanical Name: Cajanus cajan.
- Family: Leguminosae (also known by its newer name, Fabaceae).
- Origin: Africa is considered its primary center of origin, while India is a major center of genetic diversity.
- Common Names: Arhar, Tur, Red Gram, Congo Pea, and No-eye Pea.
- Global Rank: India ranks 1st in both area and production globally, accounting for roughly 90% of the area and 85% of the production.
- National Rank: In India, it is the second most important pulse crop after Chickpea.
- Botany: It features a deep tap root system and exhibits hypogeal germination. Its growth habit is characterized as an indeterminate, woody shrub.
- Pollination: Unlike many other pulses, Pigeonpea is an often cross-pollinated crop.
🚜 2. The "Biological Plow"
- Pigeonpea is famously known as the "Biological Plow".
- Why? Because its extremely deep root system acts like a plow, naturally penetrating and breaking the hard pan of the soil.
🥗 3. Nutritional Value & Protein Synergy
- Protein Content: It contains a rich amount of protein, generally ranging from 20% to 22%.
- Minerals: It is also a good source of essential minerals like Iron and Iodine.
- The "Dal-Chawal" Synergy: Cereal crops (like wheat and rice) are deficient in the amino acid Lysine. Pigeonpea is highly rich in Lysine, which is why eating cereals and pulses together (like dal-chawal or dal-roti) provides a complete amino acid dose.
⚖️ 4. Classification: Arhar vs. Tur
Pigeonpea is generally divided into two main botanical varieties:
- Cajanus cajan var. bicolor (Generally known as Arhar): These are late-maturing, taller plants that are primarily suited for and popular in North India.
- Cajanus cajan var. flavus (Generally known as Tur): These are early-maturing, shorter plants that are very popular in South India.
🌦️ 5. Climate & Soil Requirements
- Climate: It is a tropical and subtropical crop that is highly drought-tolerant.
- Sensitivities: Pigeonpea is highly sensitive to frost and waterlogging.
- Temperature: The optimum temperature for vegetative growth (rainy season) is 26°C to 30°C, and for flowering/pod filling (post-rainy season) it is 17°C to 22°C.
- Soil: Well-drained sandy-loam to clay-loam soil is best. Pure clay must be avoided as it causes waterlogging. It can tolerate a pH of 7 to 8 but is sensitive to high salinity and alkalinity.
🌱 6. Important Varieties (Highly Tested!)
- First Hybrid: ICPH-8, which was released by ICRISAT.
- Short Duration / Early Varieties: UPAS 120 (matures in just 120 days), Pant A3, and Pragati.
- Long Duration Varieties: Bahar and Narendra Arhar 1 (takes more than 180 days to mature).
- Wilt Resistant: Azad, Amar, Maruti, and Asha.
- Sterility Mosaic Resistant: Bahar, Pusa 885, Narendra Arhar 1, and Sharad.
- Winter (Rabi) Varieties: Sharad and Bahar are commonly sown in September, especially in regions like Bihar.
📏 7. Agronomy: Seed Rate, Spacing & Sowing
- Lowest Harvest Index: Take note that among all pulse crops, Pigeonpea has the lowest harvest index, sitting at just 19%.
- Field Preparation: Deep summer plowing (2-3 times) is highly recommended to eliminate weeds and pathogens.
- Sowing Method: Sowing via the Ridge and Furrow method is ideal as it effectively avoids waterlogging.
- Sowing Time: Primarily a Kharif crop, sown at the onset of the monsoon (June-July).
- Seed Rate:
- For Early/Short duration varieties: 20 to 25 kg/ha.
- For Normal/Medium/Long duration varieties: 12 to 15 kg/ha.
- Spacing: Requires wider spacing. Usually 60 to 75 cm (row-to-row) x 15 to 20 cm (plant-to-plant). Short duration varieties can be planted closer at 45 x 10-15 cm.
- Sowing Depth: 3 to 5 cm.
🛡️ 8. Seed Treatment: The F.I.R. Sequence
If treating seeds with multiple agents, always follow the F.I.R. sequence:
- Fungicide: Thiram + Carbendazim (or Trichoderma viride for wilt control).
- Insecticide.
- Rhizobium: Specifically Rhizobium leguminosarum to improve nitrogen fixation.
💧 9. Fertilizers & Water Management
- Fertilizers (NPK): The recommended dose is 20 kg Nitrogen, 40-50 kg Phosphorus, and 20 kg Potassium per hectare (20:40:20 or 20:50:20).
- Sulfur & Zinc: Applying 20 kg/ha of Sulfur helps improve protein content. If Zinc is deficient, apply 25 kg/ha of ZnSO4.
- Water Management: Primarily grown as a rainfed crop. If irrigation is needed, the two most critical stages are the Pre-flowering/Branching stage and the Pod formation/Grain filling stage.
🌿 10. Weed Management & Intercropping
- Critical Weed Period: The first 60 days face the highest crop-weed competition.
- Herbicides: Pre-emergence application of Pendimethalin (1 kg a.i./ha) is widely used.
- Intercropping Champion: Because Pigeonpea is a very slow-growing crop in its initial period, it is considered the ideal crop for intercropping systems.
- Common Intercrops: It is heavily intercropped with Sorghum (1:2 or 2:1 ratio) or Groundnut (1:6 or 1:7 ratio).
- Crop Rotation: Maize-Pigeonpea or Pigeonpea-Wheat are considered highly effective crop rotations.
🐛 11. Major Pests and Diseases
Always memorize the scientific names for these critical threats:
- Gram Pod Borer: Helicoverpa armigera.
- Tur Pod Fly: Melanagromyza obtusa (highly important pest).
- Wilt Disease: A major soil-borne fungal disease caused by Fusarium udum, leading to black roots and vascular discoloration.
- Sterility Mosaic Disease (The Green Plague): A viral disease that causes plants to become yellow and thin, and utterly fail to produce any flowers or pods. It is famously called the "Green Plague".
- Vector of SMD: The Sterility Mosaic Virus is spread by an Eriophyid mite known scientifically as Aceria cajani.
🚜 12. Harvesting & Yield
- Harvesting Stage: Never wait for the entire plant to dry, as it will lead to massive seed shattering in the field. Harvest when 75% to 80% of the pods turn brown/dry.
- Yield:
- Rainfed conditions: 10 to 15 quintals/hectare.
- Irrigated conditions: 20 to 25 quintals/hectare.
