Soil Nutrients Status and Cotton Yield as Influenced by Split Application of Nitrogen and Potassium in Vertisol

Abstract

The present investigation was conducted during 2018-19 with a view to study the effect of split application of nitrogen and potassium on yield of cotton and soil nutrient status at Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola. The experiment comprised of eight different treatments and their combination with foliar spray of 1 per cent MgSO4 at two different growth stages viz. flowering and boll development in randomized block design with three replications. The results of the present experiment revealed that, available nutrient status of soil was slightly increased with increase in the splits of N and K fertilizer. Available N, P, K, S and exchangeable Ca in soil were significantly increased with the split application of fertilizer. The fertilizer split did not show significant effect on the exchangeable magnesium status of soil. Foliar sprays of 1 per cent MgSO4 at two different growth stages viz. flowering and boll development irrespective of fertility levels showed slightly higher exchangeable magnesium status of soil. The lowest available N, P, K, S and exchangeable Ca and Mg was recorded in treatment of absolute control. The fertilizer splits show a consistent increase in the seed cotton yield and stalk yield of Bt cotton. Hence, it can be concluded that, application of 60:30:30 N, P2O5 and K2O kg ha-1 with splits of nitrogen at basal, 30, 60 and 90 DAS, 100 per cent P2O5 as basal and K2O in two equal splits at basal and 60 DAS recorded significantly higher seed cotton and cotton stalk yield. The seed cotton (R2 = 0.913**) and stalk yield (R2 = 0.935**) was significantly and positively correlated with the soil organic carbon status.