Abstract

                                A Study was made of the heterosis in relation to combining ability and per se performance for yield and six compenent traits in the varietal hybrids obtained in e diellel cross of 12 varieties observed for all characters. The highest heterosis of 165 per cent was observed for productive tillers followed by penicle weight, grains per panicle, plant yield, 1000 seed weight and days for first flowering for earlines, Hete- rosis for yield was mostly due to simultaneous heterosis for productive tillers, ponicle weight and giains per panicle. There was a variable relationship between heterosit and combining ability effects. In general s. c. a, and g. c. a. had a pronounced effect on hetetosis either singly or in association with each other. Hybrids with high hete- rotic response were mostly found with high per se performance and vice versa. The Dossibility of growing hybrid rice with attendant heterosis for yield, productive tillers: panicle weight and grains per panicle was discussed.

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