Heterosis and inbreeding depression for yield and kernel characters in scented rice

An investigation was undertaken to study the nature and magnitude of heterosis and inbreeding depression in rice for yield components and kernel characters involving 10 parents, 45 F1s and corresponding F2s. High degree of heterosis was observed for plant height, productive tillers plant-1, panicle length, filled grains panicle-1, test weight and grain yield plant-1, whereas in case of days to 50% flowering, kernel length (KL), kernel breadth (KB) and KL/KB ratio, it was low. Four cross combinations viz., Pakistani Basmati/Mahi Sugandha, Basmati 370/IET 13846, IET 16320/IET13846 and IET13846/Kasturi exhibited higher magnitudes of heterobeltiosis in F1 coupled with high inbreeding depression in F2 for grain yield plant-1, indicating predominant role of non-additive gene action in its inheritance. Such high heterosis for grain yield was due to additive heterotic effect of one or more component traits.

Author : L. L. Panwar and Mashiat Ali