Zero Tillage Plus Residue Management and K Fertilization Effect on Cotton Yield and K Use Efficiency in Wheat-Cotton System

Zero tillage straw retained with optimum K is an important strategy to increase cotton ( Gossypium hirsutum L.) yield and K efficiency in wheat ( Triticum aestivum L.)-cotton system. A 2 years field experiment was conducted during 2018, and 2019 to study the impact of [zero tillage straw as such on soil surface (ZT SAS ) and zero tillage straw burnt (ZT SB )] and five K rates were 0, 20, 40, 60 and 80 kg ha -1 on cotton yield and K use efficiency. Results indicated that bolls/plant –1 , weight per boll, seed cotton yields, ginning out turn and K agronomic efficiency were highest with 60-80 kg K ha –1 . Interactions revealed that ZT SAS with 60-80 kg K ha –1 had higher bolls/plant, bolls weight, seed cotton yields and ginning out turn compared to ZT SB . K agronomic efficiency indices decreased with increasing K rate. ZT SAS with 20 kg K ha –1 gave greater K agronomic efficiency than other combinations. ZT SAS with 60-80 kg potassium per hectare may be a sustainable and environmentally safe strategy to enhance cotton yield and soil fertility . Keywords: Zero tillage, residue management, potassium, cotton yield, K agronomic efficiency DOI: 10.7176/CPER/64-03 Publication date: January 31 st 2022