Effect of long-term application of potassium and phosphorus fertilizers on yield and K uptake of crops under different cropping sequences.

摘要

The effects of K (0, 30, 60 or 90 kg/ha) and P (0 and 60 kg/ha) on the performance of pearl millet-wheat, sorghum-wheat and moong bean-wheat rotations were studied in Hisar, Haryana, India, during 2000-01, 2001-02, 2002-03, 2003-04 and 2005-06. During the kharif season, P at 60 kg/ha significantly increased the grain and straw yields of all crops. The increase in grain and straw yields due to K application was significant up to 60 kg/ha only. P increased K uptake by grains of pearl millet and moong bean by 7.36-9.56 and 7.92-10.29 kg/ha, respectively. K uptake by the straw of pearl millet, sorghum and moong bean [Vigna radiata] increased due to P application from 118.37 to 146.84 kg/ha, from 115.06 to 136.45 kg/ha, and from 59.54 to 69.67 kg/ha. K increased K uptake by grains of pearl millet and moong bean from 6.97 to 10.13 kg/ha, and from 7.25 to 10.21 kg/ha. K uptake by straw of pearl millet, sorghum and moong bean increased from 126.68 to 137.13 kg/ha, from 120.47 to 131.51 kg/ha, and from 51.60 to 74.21 kg/ha. During the rabi season, P increased the grain yields of pearl millet, sorghum and moong bean by an average of 9.56, 8.50 and 9.40 quintal/ha, respectively; the corresponding increases in straw yield were 18.89, 18.20 and 16.35 quintal/ha. In general, K increased the straw yield of wheat grown after the various kharif crops. The increase in grain yield due to K application was significant only in wheat grown after sorghum and supplied with 90 kg K/ha. K uptake by grain and straw was also enhanced by P and K. [1.0 quintal=100.0 kg].