INFLUENCE OF VERMICOMPOST APPLICATION ON THE AVAILABLE MACRONUTRIENTS AND SELECTED MICROBIAL-POPULATIONS IN A PADDY FIELD

The possibility of reducing the use of chemical fertiliser by using vermicompost as organic fertiliser was tested on the summer crop of paddy variety ''HAMSA''. The control plot received the recommended dosage of farm yard manure and the chemical fertilisers. The experimental plot received half the recommended dosage of chemical fertilisers and the vermicompost. At the time of seed setting and 2 months after the harvest of the crop, the soil samples were analysed for total microbes, N-fixers, Actinomycetes and spore formers. The percent Mycorrhizal colonisation in the plant system was also assessed. Significant increase in the colonisation of these microbes in the experimental plot over the control plot was observed. The symbiotic association of Mycorrhizae in the roots showed a remarkable difference in infection which was just 2.85% in control plots compared to 10% in the experimental plot. Except for Actinomycetes, the colonies of the other microbes assessed 2 months after the harvest of the crop in the drained plots, showed significantly higher counts in the experimental plots. The stubbles in experimental plots retained higher counts of Mycorrhizae than those in the control plots. It could be deduced that the vermicompost application has enhanced the activity of these selected microbes in the soil system. There was high level of Total N in the experimental plot which comparatively received less quantity of fertilisers. This may be due to the higher count of N-fixers (3.48 x 10(3)) observed in the experimental plot than that of the control plot (2.16 x 10(3)).