Abstract

                                A study with 12 crosses involving short duration rice varieties revealed the predominant role of dominance components over additive components for all the traits stuched, indicating the possibility of exploiting hybrid vigour. Additive X additive for ear bearing tillers per plant, grain number per car and 100-grain weight, additive X dominance for plant height and dominance X dominance for ear length and grain yield were the major components of genetic variance. For all the traits, the most common was the complementary type of epistasis. The crosses Co 41 X ADT 37 and IR 50 X ADT 37 were identified as promising to exploit both additive and additive X additive components in varietal improvement programme through the use of biparental mating in F2 generation.

Key words :