Abstract:  In order to clarify the effects of photoperiod on diapause termination and reproductive development of Chrysoperla sinica (Tjeder), the dry weight, supercooling point (SCP), freezing point (FP), and the water, protein and glycogen contents in overwintering adults of C. sinica were investigated under the long (15L∶9D) and short  (9L∶15D) photoperiods in the laboratory conditions. The results showed that the dry weight of female adults under the long photoperiod was higher than that under the short photoperiod, contrary to male adults. The water contents of the female and male adults showed an upward tendency under both photoperiods and increased significantly under the long photoperiod (P<0.05). SCP and FP of the female and male adults had no significant differences among the treatments under the short photoperiod, but decreased first and then increased significantly under the long photoperiod (P<0.05). The protein contents of the female adults treated for 15 d and the male adults treated for 10 d under the short photoperiod were significantly lower those under the long photoperiod (P<0.01). The glycogen contents of the male and female adults under the long photoperiod were significantly lower than those under short photoperiod (P<0.01). The univariate analysis showed that the photoperiod had significant effects on SCP, FP and glycogen content of adults during the termination of diapause, however, no significant effects on the dry weight, and water and protein contents. The treatment time had significant effects on the dry weight, SCP, FP, and the water, protein and glycogen contents (P<0.01). The sex only affected significantly the FP and the glycogen content (P<0.05). The interaction of the three factors had significant effects on SCP， FP, and the protein and glycogen contents. The analysis of biochemical compounds in the newly ovipositing adults under different photoperiods showed that the protein and glycogen contents in female and male adults under the long photoperiod were significantly lower than those under the short photoperiod (P<0.01), while the water content in male adults was significantly higher than that in female adults (P<0.01). The results suggest that the overwintering green lacewing could terminate diapause under both long and short photoperiods, with different physiological and biochemical responses during diapause termination.

Key words: Chrysoperla sinica, overwintering adult, photoperiod, diapause termination, supercooling point, freezing point, protein, glycogen, water content, body weigh