Response of rice (Oryza sativa) varieties to different levels of nitrogen under rainfed upland condition of Mizoram

A field experiment was conducted during 2012 and 2013 at Kolasib District of Mizoram on the response of rice (Oryza sativa L) varieties to different levels of nitrogen. Plant height and dry matter production were the highest with ‘Bhalum 3’ at 90 kg N/ha. Panicles/m², filled grains/panicle, grain (4.50 tons/ha) and straw yield and nitogen uptake by grain and straw were also significantly higher with ‘Bhalum 3’. Increasing levels of nitrogen enhanced panicles/m², filled grains/panicle, grain and straw yield and nitrogen uptake by grain and straw only up to 90 kg N/ha. Varieties and nitrogen levels interacted significantly and the highest grain yield and economics were recorded with ‘Bhalum 3’ at 90 kg N/ha and it was found to be optimum combination for upland rice.