GROWTH, RESERVE REMOBILIZATION AND ITS CONTRIBUTION TO THE YIELD OF HYBRID RICE VARIETIES IN AMAN SEASON

Abstract

The experiment was conducted at the Research Farm of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar. Dhaka to evaluate the growth, reserve remobilization and its contribution to the yield of hybrid rice varieties in Aman season. The experiment was laid out in Randomized Complete Block Design with three replications. Seven rice variety viz. BRRI dhan46, BRRI hybrid dhan2, Heera2, Fin, Alomn, Sonarbangla3 and Taj were used as test crop. Growth characters yield and yield attributes were significantly varied among the studied varieties. Heera2 exhibited superiority over other hybrid and inbred varieties in respect of growth characters like tillers hiw', leaf area index (LA!), stem dry matter hill' leaf dry matter hill', total dry matter hill'. The highest shoot dry matter at pre- and post-anthesis stages (29.88 g m 2 and 25.03 g m 2) was achieved in Heera2 while the lowest was (23.98 g m 2 and 21.56 g m2) in BRRI dhan46. The significantly highest shoot reserve translocation (16.23%) was recorded from Heera2, while the lowest (10.09%) was achieved from BRRI dhan46. All the hybrids exhibited higher shoot reserve translocation compared to the used inbred. Yield components viz. panicles hill' 1000-grain weight, spikelets fertility (%) mainly contributed to the higher grain yield of hybrid varieties. The significantly highest grain yield (7.70 t ha") were obtained from Heera 2 which was closely followed by Sonarbangla3 (7.37 t ha") and the lowest (4.12 t ha") was recorded from BR.R1 dhan46. All the hybrid rice varieties exhibited higher grain yield over the inbred in Amati season.