INTEGRATED PHOSPHORUS MANAGEMENT IN SOYBEAN-WHEAT CROPPING SYSTEM

摘要

A 2- year field study on vertisol showed that application of 10 t ha~(-1) Farm Yard Manure (FYM) to soybean [Glycine max (L) Merrill] brought significant improvement in grain yield and favorable residual effect on succeeding wheat (Triticum aestivum L. emend Fiori & Paol) crop. Application of 30 kg P_2O_5 ha~(-1) produced significantly higher grain yield of soybean. Residual effect of 60 kg P_2O_5 ha~(-1) recorded the highest grain yield of succeeding wheat crop. Seed and soil inoculation with Phosphate Solubilizing Microorganisms (PSM) were found to be on par. Soybean grain yield was enhanced by about 4 per cent due to PSM inoculation. Wheat crop grown on the residual soil fertility left over by soybean, in which PSM inoculation was done, producedhigher grain yield. Phosphorus (P) requirement of soybean - wheat cropping system could be fulfilled by the application of 10t FYM ha~(-1) along with 30 kg P_2O_5 ha~(-1) and inoculation with PSM to soybean in Kharif season. The residual effect of this combination on the productivity of wheat was comparable to the direct application of 60 kg P_2O_5 ha~(-1) to wheat crop grown in sequence with soybean. The optimum doses of fertilizer-P for the soybean- wheat cropping system were worked out to be 41.88 and 35.85 kg P_2O_5 ha~(-1) with seed and soil inoculation with PSM, respectively.