Response of Cotton to Tillage Plus Wheat Residue and Potassium Management in Wheat-Cotton System

Conservation tillage with straw retention and optimizing potassium is an important strategy to enhance soil quality and cotton yield in the wheat-cotton system. Field experiments were conducted to study the effect of six tillage methods (zero tillage straw as such on the soil surface (ZTsas), ZTstraw removed (ZTsr), reduced tillage straw incorporated (RTsi), RT straw removed (RTsr), conventional tillage straw incorporated (CTsi), CT straw removed (CTsr)) and three potassium rates (30, 60 and 90 kg ha-1) on cotton yield and quality. Results showed that RTsi produced higher boll count, weight per boll, seed cotton yield, ginning out turn than all other tillage methods. Mean bolls plant-1, boll weight, seed cotton yield, ginning out-turn, and fiber length were optimum at 60-90 kg K ha-1. Interaction showed optimum bolls, boll weight, yield and GOT with 60 kg K ha-1 under conservation tillage. RTsi with 60 kg K ha-1 also performed better in terms of fibre length and strength. ZTsas and RTsi with 60 kg K ha-1 produced higher total soil K at the end of two year experimentation. In conclusion, conservation tillage plus straw retention with 60 kg K ha-1 may be a sustainable and environmentally safe strategy to enhance cotton yield and quality.