Effect of organic manures and lime on nutrient availability and soil enzyme activity under upland rice in North Eastern Himalayan Region

Abstract

A field experiment was conducted to evaluate the effect of various nutrient sources and lime on nutrient availability and soil enzymatic activities in upland rice in North Eastern Himalayan region, Meghalaya. The experiment was laid out in FRBD (Factorial Randomized Block Design), with three replications and twelve treatment combinations (Control, 100% RDN through inorganic means, 100%RDN through FYM, 50%RDN through FYM+50%RDN through Vermicompost (VC), 50%RDN though FYM+50%RDN through Poultry manures (PM), 50%RDN though FYM+50%RDN through Pig Manures (SM), each treatment alternatively supplemented with lime @ 400 kg/ha). Available N, P, K, Fe, Zn were significantly higher in 50% FYM + 50% SM followed by 50% FYM + 50% PM over control. Enzyme activities as observed for dehydrogenase, fluorescein diacetate and soil microbial biomass carbon were significantly higher by 78.6%, 47.0% and 44.5% in 50% FYM + 50% SM at harvest. Urease enzyme activity was highest in 100% inorganic at flowering. The increase in enzyme activity due to liming was not found.