Gaurav U. Karad, M.B. Viradiya, S. P. Deshmukh and R.D. Shinde
Abstract
The effect of integrated nutrient management (INM) on active pools of soil organic carbon (SOC) under groundnut-wheat cropping sequence of a Haplustepts soil was studied in a long-term field experiment initiated during kharif 1999 at Junagadh, Gujarat. Effect of varying doses of N, NP, NPK with FYM, Zn, S and Rhizobium on yield and carbon mineralization after 12th year of groundnut-wheat crop sequence was studied. Application of 50% NPK + FYM @ 10 t ha-1to groundnut and 100% NPK to wheat significantly increased the yield and carbon mineralization.The carbon mineralization fraction ascribed highly significant positive relationship with organic carbon (r=0.793**) and groundnut haulm yield (r=0.0.635**). Significant positive relationship with wheat grain yield (r=0.577*). The highest per cent depletion of carbon mineralization noted 66.8 % in T4, lowest depletion occurred 48.3 % in treatment T8. Integrated use of FYM with chemical fertilizers or use of FYM alone exerted significant effect on the carbon mineralization of soil organic carbon.