Heterosis in Hybrids between Local and High Yielding Rice (Oryza sativa L.) Varieties of Bangladesh

Abstract

Heterosis was estimated on hybrids derived after crossing in between three local and three high yielding (HYV) rice varieties. As local rice varieties Kaika Binni, Karaila Dhan and Kachra, and as HYV rice BR23, BRRI Dhan 32, and BRRI Dhan 37 were utilized. Data on plant height, number of total and effective tillers per plant, panicle length, number of total and filled grains per panicle, percent seed set per panicle, 1000 grains weight and weight of grains per panicle of the parents and the hybrids were collected. The average success rate of crossing using HYV varieties as female was 24.46% where the highest cross success (66.25%) was achieved in BRRI Dhan 37 x Kaika Binni. But the reciprocal crosses gave an average of 16.05% success where the highest crossing success was 48.33% in Kachra x BRRI Dhan 32. BRRI Dhan 37 x Kaika Binni showed highest positive heterosis over mid (71.76%) and better parent (58.70%) respectively for number of tillers per hills whereas BRRI Dhan 37 x Karaila Dhan (18.19% of mid parent heterosis) and Kaika Binni x BRRI Dhan 32 (10.59% of better parent heterosis) performed lowest positive heterosis in respect of 1000 grain weight. Among the 18 crosses of the three local and HYV rice varieties, considerable significant positive heterosis were found in few of their F1 progeny. However, major significant heterosis in terms of yield and yield contributing traits over their mid parent and better parent was observed in F1 line of BRRI Dhan 37 x Kaika Binni and their reciprocal cross. The outcome of this investigation would be utilized for further development of breeding lines of rice cultivars.