Abstract

                                An experiment was conducted with six indigenous nitrification inhibitors namely neem oil, neem cake extract, maliua cake extract, coal tar extract, sulphathiazol and direct application of neem cake. The inhibitors were tried at two concentrations. The fertilizer urea was applied at 50 and 100 kg/ha. The results showed that the efficacy of the inhibitors was in the following order viz. coal tar extract sulphathiazol > mahua- cake extract, noem cake extract, neem oil neem cake applied directly. The study revealed that there was mineralization of urea only between 20 to 30 days from the date of application i. e upto 20 days the effect of inhibitor was there in the soil. The inhibitors applied at higher concentration gave better results.

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