Effect of Potassium on Pearl millet-Wheat Cropping System in Coarse Textured Soils of Southern Haryana

A field study was carried out on a loamy sand soil of southern Haryana for eight years (2002 to 2010) to study the direct effect of potassium application (0, 30 and 60 kg K2O ha−1, applied in rabi) on wheat and its residual effect on pearl millet in pearl millet-wheat cropping system. The results revealed that wheat responded significantly to direct application of potassium up to 30 kg K2O ha−1, whereas its residual effect on pearl millet was found to be significant at 60 kg K2O ha−1. The potassium application significantly increased crop yield and K uptake by wheat and pearl millet. The mean available K status of soil decreased to 105.0, 127.5 and 145.3 kg K ha−1 with lower N and to 101.1, 126.9 and 141.0 kg K ha−1 with higher N levels at 0, 30 and 60 kg K2O ha−1 treatments, respectively from the mean initial available K of 158 kg ha−1 after harvest of eight years of continuous pearl millet-wheat cropping system.