[Super-cooling ability and its relations to body's water and fat contents of overwintering Hyphantrian cunea (Lepidoptera: Arcidae) pupae].

The determinations of super-cooling ability and body's water and fat contents of overwintering Hyphantria cunea pupae showed that during overwintering,the female and male H.cunea pupae had the similar change patterns in their cold-resistance ability,i.e.,increased with decreasing air temperature,but their body's water and fat contents,super-cooling point(SCP),and freezing point(FP) differed at different overwintering stages.The SCP was significantly lower at pre-and mid-overwintering stages than at late-overwintering stage,while FP had less difference among the stages.The body's water content was significantly higher at mid-overwintering stage than at pre-and late-overwintering stages.Comparing with non-overwintering pupae,the overwintering pupae had significantly lower SCP and FP,but significantly higher body's water and total fat contents.Regression analysis showed that there was a negative relationship between the water content and the SCP of female and male pupae(P0.05).