Abstract:To verify the combining ability of photosynthetic characteristics of function leaves, thirty hybrid combinations were obtained from incomplete diallel cross between six sterile lines and five restorer lines of indica hybrid rice cultivars. The photosynthetic characteristics in hybrid combinations and their parents were measured and statistically analyzed. Result showed that there were significant genetic differences among hybrid rice combinations in photosynthetic characteristics. The genetic variations of photosynthetic characteristics mainly came from additive effect of genes. Intercellular CO2 concentration, transpiration rate, chlorophyll content (a & b) and carotenoid content were influenced greater by sterile lines than the restorer lines but stomatal conductance, chlorophyll content (a+b) were influenced greater by restorer lines than the sterile lines. The broad genetic heritability was greater than narrow genetic heritability in photosynthetic characteristics of indica hybrid rice combinations. Each trait was mainly affected by gene interactions as well as environmental factors. The nine phenotypic values of photosynthetic traits of indica hybrid rice combinations were highly correlated (p<0.01) with the sum of the general combining ability (GCA) of parents Thus, it is possible to predict the phenotypic values of photosynthetic traits in indica hybrid rice combinations according to the GCA of parents, which is helpful for efficiently breed higher photosynthetic efficiency indica hybrid rice combinations.