COMBINING ABILITY AND GENETIC VARIANCE COMPONENTS OF A DIALLEL CROSSES AMONG RESTORER LINES OF RICE (Oryza sativa, L.).

Abstract

Fifteen hybrids were produced from a partial diallel crosses mating design among six lines. They were studied along with their parents for combining ability and genetic variations for yield and its component characters. Both GCA and SCA variances were found to be highly significant for all the characters indicating the importance of both additive and non-additive gene action. However, preponderance of non-additive (dominance) gene action was recorded for grain yield plant -1 , panicles plant -1 , filled grains panicle -1 and spikelets fertility % while 1000-grain weight was controlled by additive type.The restorer rice genotype , PR78, PR2 and Giza 178R were found to be good combiners for grain yield plant -1 and most of yield component characters. The crosses involving the above parents were promising because they showed high SCA effects.