Cotton irrigation regime under conditions of regulated water deficit

Field trial on cotton (Perla cultivar) was carried out during the 2001 - 2006 period on leached vertisols under irrigation regime of sprinkling - 75 % of the field moisture capacity (FMC) for the soil layer of 0-40 cm. The trial included the following variants: 1. Two irrigations of 400mm per hectare - the first one at the bud formation stage and the second - at the blooming stage; 2. Two irrigations of 400 mm - the first one at the blooming stage and the second at the boll formation stage; 3. Single irrigation of 500 mm at the blooming stage; 4. Single irrigation of 600 mm at the blooming - boll formations period; 5. Non - irrigated variant - standard. Ir was established that the best results were obtained at the variant with second time irrigation provides 36.0% (747 kg/ha) higher yield ad compared to non - irrigated cotton. This irrigation regime realizes higher productivity per 1000 m^3 per hectare irrigating water producing 934 kg/ha more seed cotton than the non - irrigated variant