Potassium Response in Indian Mustard in Coarse Textured Soils of Southren Haryana

Field experiments were carried out on loamy sand soils of southern Haryana for three years (2007 to 2010) to study the effect of potassium application (0, 20, 40 and 60 kg K2O ha−1) on Indian mustard (Brassica juncea L. cv. RH-8812). The results revealed that mustard crop responded to potassium application significantly up to 20 kg K2O ha−1. The potassium application significantly increased mustard seed yield by 8.3, 12.5 and 14.6% while the corresponding increase in mustard straw yield was 7.7, 11.5 and 13.4% at 20, 40 and 60 kg K2O ha−1, respectively over control. The K content and K uptake by mustard crop increased with potassium fertilizer application to the soil. The oil and protein content of mustard seed also increased with application of potassium. The mean available K status of soil decreased to 167.0, 168.5 and 169.1 kg K ha−1 from mean initial K status (169.6 kg K ha−1) at 0, 20 and 40 kg K2O ha−1; respectively, after the harvest of mustard crop. However, application of 60 kg K2O ha−1 could sustain the mean available K status of soil to 169.8 kg K ha−1.