Abstract

                                Laboratory studies were conducted with five soils of varied textural classes treated with different sources of organic manures, viz. farmyard, poultry and swine manures at the rate of 15 tons/ha for a period of 4 months. Analyses of the incu bated soils showed that the application of organic manures significantly increased the contents of total and available N and available P in all the soils studied. A significantly higher release of plant nutrients was recorded in soils treated with swine manure followed by poultry and farmyard manures. Application of farmyard manure (FYM) significantly increased the organic carbon content and cation exchange capa- city of the soils more than poultry and swine manures. Water holding capacity was also increased significantly in all textural classes except in the sandy loam. In general, addition of the organic manures significantly improved the physico-chemical properties of the soils.

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