Effect of Decomposition of Organic Matter on the Activities of Microorganisms and Availability of Nitrogen, Phosphorus and Sulphur in Soil

In an incubation study organic matter namely, berseem straw, bagasse and rice straw, Cassia sophera, Cestrum diurnum and Ipomoea cornea, augmented significantly aerobic non-symbiotic nitrogen fixing bacteria, phosphate solubilizing and sulphur oxidizing microorganisms as well as their activities, viz. nitrogen fixing, phosphate solubilizing and thiosulphate oxidizing capacities of the soil Typic Fluvaquent resulting in greater availability of N, P and S in soil solution. Among the organic matters, berseem straw was superior to others in this respect, excepting Ipomoea cornea which released maximum amount of available S in soil. Rice straw,on the other hand, exhibited an immobilization of ammoniacal nitrogen in soil.