Meeting Abstract
In insects, cold hardiness is plastic, and can be induced seasonally and in response to acute cold exposure. Acute cold exposure can also cause cellular damage, which can decrease survival of a subsequent cold exposure. Thus, a cold snap can have physiological carryover effects that impact responses to subsequent cold. These carryover effects depend on the severity of cold stress experienced. We aimed to test for carryover effects of cold exposure in overwintering adult willow leaf beetles (Chrysomela aeneicollis). We manipulated duration, intensity, and number of cold exposure, and recorded survival of a subsequent cold stress. We measured cryoprotectant levels, which prevent cold injury and are accumulated seasonally and in response to cold exposure. Relatively mild cold exposures did not influence survival to a subsequent cold stress, but a more intense cold exposure reduced survival. High cryoprotectant abundance was positively related to survival after a subsequent cold exposure, regardless of type of cold exposure. There was no difference in cryoprotectant accumulation between treatments indicating that rapid cryoprotectant synthesis may be limited in these beetles at low overwintering temperatures. This data suggest that carryover effects will not occur in response to mild cold exposures, but that severe cold could cause damage that reduces resistance to subsequent cold snaps.
