INFLUENCE OF NITROGEN AND SEEDLING TYPE ON GROWTH AND YIELD OF T. Aman (cv. BRRI dhan46)

Abstract

A field experiment was conducted at the experimental field of Agronomy Department of Sher-e-Bangla Agricultural University, Dhaka during the period from August 2008 to January 2009, to study the influence of nitrogen levels and seedling types on growth and yield of T. aman rice (cv. BRRI dhan46). The experiment comprised five levels of nitrogen: 50% lower nitrogen than recommended dose (N ), 25% lower nitrogen than recommended dose (N 2 ), recommended dose of nitrogen (N 3 1 ), 25 % higher nitrogen than recommended dose (N 4 ) and 50 % higher nitrogen than recommended dose (N ) and three types of seedling: seedling grown in wet seedbed (S 1 5 ), seedling grown in floating seedbed (S ) and seedling grown in dapog seedbed (S ) in Split-Plot design. Twenty five percent higher nitrogen than recommended dose of nitrogen (N 3 4 ) showed highest grain yield (4.93t ha -1 ), for highest dry matter hill -1 (17.83 g, 33.50 g and 45.16g, respectively at 60 DAT, 90 DAT and harvest), effective tillers hill -1 (10.38), filled grains panicle -1 (88.55) and harvest index (47.27%). Seedling grown in wet seedbed (S 1 ) showed highest grain yield (4.73 t ha ), with highest tillers hill -1 (5.57, 10.10, 13.04 and 14.24, respectively for 20, 40, 60 and 80 DAT), effective tillers hill -1 (10.16), panicle length (24.21 cm), filled grains panicle -1 (89.50), and harvest index (45.93%). The highest grain yield (5.60 t ha -1 ) was obtained from 25% higher nitrogen than recommended dose of nitrogen along with seedlings of wet seedbed and at par with the yield (5.40 t ha -1 ) from recommended dose of nitrogen with seedling from wet seedbed. 2 -1