Climatic and Agronomic aspects of cotton
It was proved from the available evidence (from the relics of Mohanjo-daro civilization) that India was the original habitat for the old world cotton. However, in the present day world, four major cultivated species of cotton including Gossypium arboreum L., G. herbaceum L., G. hirsutum L. and G. barbadense L. are grown in the world as well as in India.
Cotton is a tropical and subtropical crop, comes up well up to 500 m mean sea level and a short cool season before harvest is useful for high yields but requires at least 180 to 200 frost-free days at maturity. Cotton requires four to five months of uniformly high emperature during its growth period. Optimum temperature for vegetative growth ranges from 21 to 28 o C while relatively higher day temperature of 27 to 32 o C and cool night favour flowering and boll formation. However, with sufficient soil moisture, the crop can withstand up to 45 o C but for shorter periods. A minimum of 500 mm of well-distributed rainfall is essential particularly in the initial stages of growth. Sunny days are important at all stages of growth particularly during flowering and maturity stages.
Lint recovery: 34 per cent
Seed oil recovery: 20 per cent
Calendar of operations
Majority of cotton cultivated in the country is under rainfed conditions (65 per cent) and only about 35 per cent has irrigation facilities. Though sowing season varies widely across the regions, majority of sowings in the country falls between March and July. Sowing under irrigated conditions takes place between March and May while it spreads between June and July under rainfed conditions.