Cotton

Botanical Name :- Gossypium spp.

Family :- Malvaceae

Origin :- India

2n :- 26, 52

Importance :-

• It is white gold.
• Backbone of textile industry.
• 45 % world's fiber need is met from cotton.
• 10 % of world's edible oil.

Classification based on origin :-

1. Southern Ethiopia

                                G. herbaceum :- 2n = 26 (Diploid)

2. India

                                G. arboreum :- 2n = 26 (Diploid)

                                G. herbaceum and G. arboreum both present genome A and known as Desi cotton / Old world cotton / Asiatic cotton.

3. South America

                                G. barbadense :- 2n = 52 (Tetraploid)

                                Known as egyptian cotton, Present genome D.

4. Central America

                                G. hirsutm :- 2n = 52 (Tetraploid)

                                Upland cotton known as American cotton.

Cotton classified based on area :-

1. Northern India

                                G. herbaceum

                                G. arboreum

2. Central / Southern India

                                G. herbaceum

                                G. arboreum

                                G. hirsutm

Crop description :-

• Tap root system deep > 1.6 m in soil.
• Cotton seed contain 14 - 26 % oil and 35% proteins.
• Germination takes place in 4 - 7 day after sowing.
• 20 - 35 days after first square formation flowering take place (60 - 80 days).
• Boll attains 90% size within 15 - 18 days.
• Mature size is attained within 25 days.
• Fiber elongation is complete by 21 - 24 days.

Branches :-

                           1. Sympodial :- Reproductive branch

                           2. Monopodial :- Vegetable branch

Temperature :-

• A temperature between 27 to 32 °C is optimum for boll development (Fruiting) and maturation but above 38 °C yield are reduced.
• Optimum temperature for vegetative growth is 21 °C.

pH :-

• 5.5 - 8 with 7 - 8 optimum.

Salinity tolerance level :-

• The crop is high tolerant to soil salinity.

Water requirement :-

• Cotton need 700 mm to 1300 mm.
• Irrigation provide when 75 % depletion of ASM (Available Soil Moisture) in clay 50% ASM at sandy loam soil.

Seed rate :-

• Bt Cotton :- 1 - 1.5 kg/ha
• Hybrid :- 2 - 3 kg/ha
• American Cotton :- 15 - 25 kg/ha
• Desi Cotton :- 12 - 18 kg/ha

Plant population :-

• Bt Cotton :- 10000 plant / ha
• Hybrid :- 67000 plant / ha

Dibbling :-

• 3 cm depth in dibbling.
• Per hole seed hybrid 2 seed.

Soil :-

• Soil depth should be more than 60 cm.
• Maximum seed cotton yield has been recorded in deep (> 90 cm) soils.

Planting :-

North Zone	Central Zone	Southern Zone
1st week of May for the new varieties and 3rd week to 1st week of June.	3 week of June to 1 week of July and irrigated land May start.	1.      June :- Karnataka 2.      June / July :- Red soil of Andhra Pradesh 3.      August :- Tamil Nadu

Interculture Operation :-

• Gap should be filled at 10th day.
• Thinning should be done at 15th day.
• Nipping after 80 - 90 days.

Yield :-

                With improve packages of practices, it is possible to get about 15 - 20 quintals of seed cotton / ha. Much higher yields (25 - 30 q/ha) may be obtained from hybrids.

Varieties :-

1. Hirsutum Varieties :-

                                        MCU - 5 (Extra long), 7, 9, 10, 11, 12

                                        LRA - 5166

2. Arboreum :-

                          Lohit, K - 9, 10, 11

3. Barbedense :-

                           Suvin (Anjali), Surabi, Sujata

4. G. herbaceum :-

                               Digivijaya

5. Hybrids :-

                    Jayalakshmi, TCHB - 213, HB - 224