Abstract: Different densities （individuals/box） （female∶male=1∶1, 2∶2, 3∶3 and 4∶4） and sex ratios （individuals/box） （female∶male=1∶0, 1∶2, 1∶3, 1∶4, 2∶1, 3∶1, 3∶2 and 4∶1） on the pre spawning period, spawning period, spawning amount, hatchability, life span and female to male sex ratio of the offspring were measured, under indoor conditions [temperature （28±1） ℃, relative humidity （70% ± 7%）, light cycle 16 h（L）∶8 h（D）]. The results showed that parthenogenesis existed in the reproduction of the adult Rhynocoris fuscipes, which could lay hatchable eggs. The different densities of male and female adults and the sex ratios of female to male showed no significant effects on the pre-spawning period and egg hatching rate, but significant impacts on spawning period, spawning amount, female-to-male sex ratio of offspring and longevity of female and male adults of Rhynocoris fuscipes. The total number of eggs laid increased with the increase of female adult density, while the number of eggs laid and nymphs hatched per female gradually decreased; the average life span of male and female adults decreased with the increase of male and female adult density. The treatment with female to male sex ratio of 2∶1 had the longest average spawning period （39.5 d）, and the average number of eggs laid per female was the highest （136.40）, and the number of nymphs hatched per female was the highest （130.30）. In the process of mating, high density gave rise to interspecific cannibalistic behavior among the adults of Rhynocoris fuscipes. Based on the results of various fertility and longevity parameters in the research, the female-to-male sex ratio of 2∶1 was the better density and sex ratio for the adult reproduction in the artificial rearing of Rhynocoris fuscipes.

Key words: Rhynocoris fuscipes Fabricius, sex ratio, male and female adult density, reproductive capacity, life span