Response of cotton to site specific nutrient management (SSNM) in Vertisols of TBP command of Karnataka

Abstract

A field study was conducted to identify critical nutrient and realization of target yield through site specific nutrient management (SSNM) comprising of five treatments viz., SSNM for target yield of 4 t ha-1, N-omission, P-omission, K-omission and farmers’ practice was carried out at farmers’ fields on participatory mode during 2015-16. Results of the study revealed that yield target 4384 kg ha-1 was comfortably achieved with SSNM (332.8-78.4-106.4 kg N-P2O5-K2O kg ha-1, respectively while N omission followed (3597 kg ha-1) by K omission (3655 kg ha-1) had significantly lower yields among all due to reduced major nutrient uptake than with SSNM. Likely, SSNM had favorable residual soil fertility than with nutrient omission. Significantly higher N, P and K uptake (284, 26 and 222 kg ha-1 respectively) was observed in SSNM (4 t ha-1) treatment which was supplied with NPK. N is the most critical element followed by K for higher and sustainable cotton production and soil productivity.