Abstract

                                Studies conducted in rice with Ratna (early). Prakash (medium) and Phalguna (late) varieties during 1984 kharif season at different nitrogen levels (0, 50, 100. 150 and 200 kg N/ha) indicated that increased level of nitrogen contributed to higher yields but reduced the production of quality (high density) grain. The 1000 grain wt was unaffected at all nitrogen levels. Wider differences observed between average and potential test weight of Ratna and Prakash and meagre difference in Phalguna indicate the extent of possible variation in grain filling pattern among varieties of different duration in relation to nitrogen levels. Higher yield recorded at higher 'N' was attributed to increased production of varied yield components such as panicle number, spikelet and grain number, as influenced by dry matter, leaf area index reflecting in higher photosynthetic efficiency. The study indicated that varieties possessing higher amount of high density grain (quality grain) are suitable for low 'N' management.

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