Abstract: Three\|line indica hybrid rice including 5 indica CMS lines with broad representation and 16 restorer lines, the grain phytic acid content and some important yield trait indexes of the hybrid rice and their parents were determined and analyzed through incomplete diallel cross, meanwhile, General combining ability(GCA) of the parents and specific combining ability(SCA) of hybrid rice for grain phytic acid content were evaluated. The results showed that both female and male parents contributed to grain phytic acid content of hybrids, but F value for variance of female parents was greater than that of male parents. The hybrid rice whose parents had low level of GCA did not always show low level of SCA. Among 80 hybrid combinations, no significantly correlation between grain phytic acid content and yield, plant height, panicle length, effective number of panicles, total number of grains, seed-setting rate or other important agronomic traits was indicated, but there was significantly positive correlation between grain phytic acid content and 1000-grain weight.

Key words: indica rice, hybrid combinations, phytic acid, combining ability, diallel cross