Cotton Crop
Complete Notes
General Overview
| Particular | Information |
|---|---|
| Common Name | Cotton |
| Scientific Name | Gossypium spp. |
| Family | Malvaceae |
| Crop Type | Kharif Cash Crop |
| Economic Product | Seed Fibre (Lint) |
| Common Titles | White Gold, King of Fibre Crops |
| Main Uses | Textile fibre, edible oil, cottonseed cake, paper, industrial products |
| Cultivated Species | G. arboreum, G. herbaceum, G. hirsutum, G. barbadense (Total: 4) |
| Most Cultivated | Gossypium hirsutum |
| Longest Staple | Gossypium barbadense |
| Largest Area | India |
| Major Countries | China, India, Brazil, USA, Pakistan |
✨ India’s Special Feature
India is the only country cultivating all four cultivated cotton species commercially.
Species & Genomics
| Species | Chrom. | Origin | Key Character |
|---|---|---|---|
| G. arboreum Desi / Tree |
2n=26 Diploid |
Origin: India | Short staple, drought & pest tolerant. |
| G. herbaceum Levant / Desi |
2n=26 Diploid |
Origin: Africa (Ethiopia-Sudan) | Short staple, handles poor rainfed soils. |
| G. hirsutum American / Upland |
2n=52 Tetraploid |
Origin: Mexico (C. America) | Medium-long; 90-95% global output. |
| G. barbadense Egyptian / Sea Isl. |
2n=52 Tetraploid |
Origin: Peru-Ecuador (S. America) | Extra-long; superior luxury textile. |
Climate, Soil & Sowing
Environmental Requirements
| Climate | Tropical and Subtropical |
| Temperature | 21–30°C (Optimum: 25–30°C) |
| Rainfall | 50–100 cm, well distributed |
| Sunshine | Bright sunshine during flowering & boll development |
| Frost Limit | Requires frost-free period of 180–200 days |
| Relative Humidity | Moderate (50-70%) |
| Best Soil | Deep Black Cotton Soil (Regur) |
| Other Soils | Alluvial, Red, and Loamy soils (Clay loam to loam) |
| Drainage & pH | Well-drained | pH: 6.0–8.0 (Optimum: 6.5–7.5) |
| Organic Matter | Rich in organic matter |
Sowing Framework
| Type / Window | Rate (kg/ha) | Spacing / Depth |
|---|---|---|
| Desi Varieties Season: Kharif |
Rate: 15–20 kg/ha | 60 × 30 cm | Depth: 3-5 cm |
| American Var. North: Apr-May(Irr), May-Jun(Rf) |
Rate: 20–25 kg/ha | 60 × 30 cm | Method: Dibbling/Drill |
| Hybrid Cotton South: Jun-Sep (Monsoon) |
Rate: 2–3 kg/ha | 90×60 / 120×60 cm | Depth: 3-5 cm |
| Bt Hybrid Cotton Genetically Modified |
Rate: 1.5–2.5 kg/ha (Or 1-1.5) | 90×60 / 120×60 cm | Fungicide Treated |
💡 Seed Texture Dynamics
Fuzzy Seed: Demands higher seed rate due to fuzz attached.
Delinted Seed: Requires lower seed rate because of better germination properties.
Nutrient Matrix (INM)
| Nutrient | Dose (kg/ha) | Application Timeline |
|---|---|---|
| Nitrogen (N) | Dose: 80-120 kg/ha | ½ basal + ½ at square/flower initiation |
| Phosphorus (P₂O₅) | Dose: 40-60 kg/ha | Full basal at sowing |
| Potash (K₂O) | Dose: 40-60 kg/ha | Full basal at sowing |
| Sulphur (S) | Dose: 20-30 kg/ha | Basal application |
| Zinc (ZnSO₄) | Dose: 25 kg/ha | Basal application (if deficient) |
| Boron (B) | Dose: 1-2 kg or 0.2% foliar | At flowering stage (if deficient) |
Integrated Nutrient Management (INM)
| Farmyard Manure (FYM) | 10–15 t/ha applied before sowing |
| Compost / Vermi | 2–5 t/ha |
| Biofertilizers | Azotobacter / Azospirillum + PSB seed treatment |
| Green Manuring | Sowing Sunhemp or Dhaincha before cotton |
Deficiency Signals
| Nitrogen (N) | Older leaves turn pale yellow; stunted growth |
| Phosphorus (P) | Dark green leaves with purplish tinge; poor root growth |
| Potassium (K) | Yellowing and scorching of leaf margins |
| Sulphur (S) | Yellowing of young leaves |
| Zinc (Zn) | Small leaves, shortened internodes (rosetting) |
| Boron (B) | Poor flowering, boll shedding, malformed bolls |
Water & Irrigation
| Irrigation Rounds | 5–8 irrigations (depends on climate & soil) |
| Total Water Required | 700–1200 mm |
| Irrigation Methods | Furrow, Sprinkler, and **Drip (best system)** |
| First Irrigation | 30–40 Days After Sowing (DAS) if needed |
| Application Interval | 10–15 days (summer) | 15–20 days (winter) |
| Waterlogging Limit | Not tolerated; ensure good drainage configurations |
Critical Stages of Water Requirement
| Crop Stage | Importance |
|---|---|
| Germination & Est. | Good plant stand establishment |
| Square Formation | Critical stage (Flower Bud initiation) |
| Flowering | Most critical stage |
| Boll Formation | Critical for boll development |
| Boll Dev. / Filling | Improves field yield and fiber quality parameters |
Weed Management
Major Weed Categories
| Weed Type | Common Name | Scientific Name |
|---|---|---|
| Grassy | Jungle Rice / Crowfoot / Bermuda | E. colona / D. aegyptium / C. dactylon |
| Sedges | Purple Nut Sedge | Cyperus rotundus (Problematic) |
| Broad-leaved | Congress Grass / Horse Purslane / Pigweed | P. hysterophorus / T. portulacastrum / A. viridis |
Management Strategies
| Cultural / Mech. | Clean cultivation, rotation, spacing | 2-3 hand weedings/hoeings at 20-25 DAS & 40-45 DAS |
| Mulching | Organic or plastic mulch to suppress field weed clusters |
| Pre-emergence | Pendimethalin 30 EC @ 1.0 kg a.i./ha (within 2-3 DAS) |
| Post-emergence | Quizalofop-p-ethyl @ 50-75 g a.i./ha (for grassy weeds) |
| Directed Spray | Glyphosate or Paraquat between rows (avoid cotton contact) |
| IWM Formula | Herbicide + interculture + hand weeding |
⏱️ Critical Weed Competition Window
The core critical weed window spans from 20–60 DAS.
Plant Pathology (Diseases)
| Disease | Causal Organism | Symptoms & Management |
|---|---|---|
| Bacterial Blight (Black Arm) | Xanthomonas citri pv. malvacearum | Angular spots, stem lesions. Mgt: Resistant varieties, seed treatment. |
| Fusarium Wilt | Fusarium oxysporum f. sp. vasinfectum | Yellowing, vascular browning. Mgt: Rotation, resistant varieties. |
| Verticillium Wilt | Verticillium dahliae | Yellowing, leaf drying. Mgt: Resistant varieties, crop rotation. |
| Alternaria Spot | Alternaria macrospora | Brown circular spots. Mgt: Spray Mancozeb/Chlorothalonil. |
| Anthracnose | Colletotrichum gossypii | Dark sunken lesions on bolls. Mgt: Fungicide spray, seed treatment. |
| Grey Mildew | Ramularia areola | White-grey fungal growth. Mgt: Spray Carbendazim/Hexaconazole. |
| Root Rot | Rhizoctonia bataticola | Sudden wilting, root decay. Mgt: Seed treatment, drainage, rotation. |
| Leaf Curl Virus (CLCuD) | Cotton Leaf Curl Virus (Begomovirus) | Leaf curling, stunting. Vector: Whitefly. Mgt: Vector control setup. |
Entomology (Insect Pests)
| Insect Pest | Scientific Name | Symptoms & Management |
|---|---|---|
| Pink Bollworm (Most Destructive) | Pectinophora gossypiella | Larvae feed inside bolls, rosette flowers. Mgt: Pheromone traps, timely sowing. |
| American Bollworm | Helicoverpa armigera | Feeds on squares, flowers, and bolls. Mgt: Pheromone traps, Bt cotton, Spinosad. |
| Spotted / Spiny Bollworm | Earias vittella / E. insulana | Bores into terminal shoots and bolls. Mgt: Remove infested shoots, chemical spray. |
| Whitefly | Bemisia tabaci | Sucks sap, honeydew, transmits CLCuV. Mgt: Yellow sticky traps, Imidacloprid. |
| Jassid (Leafhopper) | Amrasca biguttula biguttula | Leaf curling and severe hopper burn. Mgt: Resistant varieties, Acetamiprid. |
| Aphid / Thrips | Aphis gossypii / Thrips tabaci | Sap sucking, leaf curling, silvery streaks. Mgt: Blue sticky traps, Neem, Spinosad. |
| Mealybug | Phenacoccus solenopsis | White waxy colonies, stunted growth. Mgt: Remove plants, bio-control, chemicals. |
| Red Cotton Bug | Dysdercus cingulatus | Sucks sap from seeds, stains fiber lint outputs. Mgt: Field sanitation, timely picking rounds. |
🧬 GM Protection Targets
Commercial Bt Cotton provides focused genetic control resistance targeting American, Pink, Spotted, and Spiny Bollworms.
Physiological Disorders
| Disorder | Primary Cause | Symptoms & Management |
|---|---|---|
| Square Shedding | Moisture stress, nutrient imbalance, insect attack | Shedding of flower buds. Mgt: Timely irrigation, pest management. |
| Flower Shedding | High temperature, drought, excess nitrogen | Flowers drop before boll formation. Mgt: Balanced NPK, irrigation setup. |
| Boll Shedding (Most Common) | Water stress, nutrient deficiency, insect damage | Young bolls fall prematurely. Mgt: Irrigation during flowering & boll dev. |
| Poor Boll Opening | Potassium deficiency, low temperature, excess moisture | Bolls fail to split open properly. Mgt: Apply potash, maintain sound irrigation logs. |
| Leaf Reddening | Potassium/Magnesium deficiency + moisture stress | Older leaves turn reddish-purple. Mgt: Apply K and Mg fertilizers explicitly. |
| Sun Scald | High temperature and intense sunlight | Brown, scorched patches on bolls. Mgt: Healthy canopy, proper irrigation. |
Harvesting & Storage
| Operation | Recommendation Metrics |
|---|---|
| Harvesting Indicator | When 50-60% bolls are fully split and opened |
| Harvesting Method | Mostly hand picking manual execution cycles |
| Number of Pickings | 3–5 pickings managed at 15–20 day intervals |
| First Picking Rule | Collect fully opened, dry bolls exclusively |
| Safe Storage Moisture | 8–10% moisture content for seed cotton |
| Storage Environment | Clean, dry, cool, and well-ventilated location |
| Stacking Method | Store on wooden pallets; avoid direct floor contact |
| Pest Protection | Keep store free from insects, rodents, and fungi |
| Pre-Storage Step | Dry seed cotton should be ginned before long storage |
Varieties & Hybrids Matrix
| Variety/Hybrid | Species Type | Special Feature Details |
|---|---|---|
| H-4 | G. hirsutum × G. barbadense | First commercial cotton hybrid in India (1970, Gujarat) |
| Varalaxmi | Hybrid | First interspecific cotton hybrid in India |
| DCH-32 | Hybrid | Extra-long staple (ELS) commercial hybrid cotton |
| MCU-5 / MCU-7 | G. hirsutum | Long staple variety choices grown widely across South India |
| LRA-5166 | G. hirsutum | Highly popular irrigated variety option |
| Suraj / AKA-7 / RG-8 | G. arboreum | Desi cotton varieties with drought tolerance / rainfed fit |
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