Quantity-Intensity Relationships of Potassium as Affected by Continuous Cropping and Fertilizer Application under Different Cropping Sequences

摘要

The quantity-intensity relationships of potassium were studied in soil samples from a long-term field experiment receiving two levels of phosphorus (0 and 60 kg P_2O_5 ha~(-1)) and four levels of potassium (0, 30, 60 and 90 kg K_2O ha'1) in every cropseason for the last 23 years. The surface (0-15 cm) soil samples were collected from different treatments under three cropping sequences viz., pearl millet-wheat, guar-wheat and jowar-wheat. Amongst the Q/I parameters, AR_0~K and K_L values were found higher in K treated plots, whereas PBC~K observed a reverse trend.