Relative Efficiency of Prilled Urea, Urea Supergranules (USG), and Coated USG by Neem (Azadirachta indica) and Dicyandiamide on Transplanted Rice

Abstract

A filed experiment was made with rice variety Pusa 169 during July to November 1986 and 1987 at the Indian Agricultural Research Institute, New Delhi, to compare the prilled urea supergranules for transplanted rice. Furthermore, the advantage of coating urea supergranules with nitrification inhibitor DCD or neem cake, an indigeneous material having nitrification inhibiting propertied, was also investigated. Application of 120 kg N/ha produced taller plants, more tillers and panicles/hill, longer and heavier panicles, more spikelets and grains/panicle and higher 1,000 grain weight than 60 kg N/ha. Crain and straw yield of rice was also significantly higher with 120 kg N/ha than 60 kg N/ha. Split application of N ( ½ dose 10 days after transplanting and the remaining ½ at panicle initiation ) gave higher numbers total and effective tillers, longer panicles, more spikelet, grains/panicle and 1,000 – grain weight. Grain and straw yields of rice were higher with split application. Urea supergranules was significantly superior to prilled urea for all the growth characters, Yield attributes, grain and straw yields. The advantage of coating urea supergranules with neem cake and DCD over uncoated urea supergranules was seen in the case of plant height, panicle/ hill length and weight of panicles, 1,000 grain weight, grain and straw yields of rice. The nitrification inhibitor can reduce ammonia volatilization, denitrification, leaching and surface runoff of nitrogen which gain to rice as said. The result of these experiment should be inform to farmer and concerned person for next stop of extension.