[en] Mature pupae (6-8 days old) of Eldana saccharina were exposed to increasing sub-sterilizing doses of ionizing gamma radiation in the range of 80-180 Gy. In the parental (P) generation, emerged male and female moths were out-crossed with untreated moths of the opposite sex. Reciprocal crosses between progeny of treated and untreated moths were also made in the F1 generation. In both generations, radiation doses used did not have any significant effect on mating behaviour of adults E. saccharina. There was also no significant difference in the mean number of spermatophores (approximately 1.0 per female) transferred by males to females during copulation among treated and control crosses. Fecundity in the parental generation was reduced by 40-44% in crosses between treated males and untreated females without any clear dose dependence. In the reciprocal crosses, however, fecundity considerably decreased with the increasing dose of radiation. The dose-dependent decreased of fecundity, similar in both reciprocal crosses, was also observed in F1 generation. Increasing doses of radiation generally resulted in decreasing fertility of treated moths in both the P and F1 generations. There was, however, a remarkable difference between reciprocal crosses. While radiation induced only partial sterility of treated P males even at the highest dose (180 Gy), treated P females exhibited a high sterility at 100 Gy. In both F1 crosses, fertility was lower than in treated P males, and F1 males exhibited a higher level of inherited sterility than F1 females. The results demonstrate a potential of using inherited sterility in integrated pest management programme to suppress the pest population of E. saccharina and other related stemborer species (author)