Nitrogen balance and organic carbon status of soils in soybean-finger millet cropping system as influenced by integrated nutrient management.

摘要

A field study was conducted in Bangalore, Karnataka, India for two years (kharif seasons of 2002 and 2003) to study the effect of integrated nutrient management on organic carbon status and nitrogen balance of soyabean-finger millet cropping system under rainfed condition. The results revealed that application of 50% N + 10 t/ha FYM (farmyard manure) recorded the highest N uptake by soyabean (112.6 kg N/ha) followed by 105 kg N/ha 50% N + 50% N through GLM (green leaf manure) + FYM + BS (biogass-slurry) + PM (poultry manure) and 100 kg N/ha under 50% N + 50% N through PM + BS + GLM + CRC (crop residue compost). The same trend of N-uptake was observed in finger millet. After finger millet crop, in both the years, the actual nitrogen balance was more in 100% N + 10 t FYM followed by 50% N + 50% N through GLM + FYM + BS + PM and 50% N + 50% N through PM + GLM + FYM + CRC. Net gain of nitrogen was recorded in 50% N + 50% N through PM + FYM + BS + CRC (166.9 kg N/ha) followed by 50% N + 50% N through PM + FYM + BS + GLM (166.6 kg N/ha). The highest net loss of N was found in absolute control (-30.9 kg N/ha). Highest organic carbon percentage was recorded in soyabean with 100% N+10 t FYM (0.51%) followed by 50% N + 50% N through PM + FYM + BS + CRC (0.50%). Similar results were recorded in finger millet. Application of 50% N + 50% N through GLM + FYM + BS + PM also performed better in improving the organic carbon status in both crops..