Abstract

                                Monthly sowings of parental lines of hybrid rice were carried out for twelve months to elucidate information on the effect of weather parameters on flowering and panicle exertion. Variations were seen among the entries tested, where IR 10198-66-2R showed extreme fluctuation in biometrical parameters recorded. Among the seasons, summer (February-May) followed by samba (October-January) were found. to have better expression of floral characters and agronomic traits. Correlation studies with weather parameters (Heat Unit Concepts), showed significant relationships. with selected parameters like days to first flowering, duration of flowering in a panicle and panicle exertion percentage and regression equations were arrived using the relationship.

Key words : Hybrid rice, Parental lines, Synchronisation, Stigma exertion, Regression equations.