Entomologia Experimentalis et Applicata (2011) 140, 85-90

Zhong-Shi Zhou, Jian-Ying Guo, Min Li, Hong-Mu Ai and Fang-Hao Wan (2011)
Seasonal changes in cold hardiness of Ophraella communa
Entomologia Experimentalis et Applicata 140 (1), 85-90
Abstract: Insects can prepare themselves to tolerate subzero temperatures through various physiological changes, such as the alteration in body water or glycerol content. Indeed, it has been hypothesized that increasing glycerol body content has the benefit of decreasing the temperature necessary to freeze their body water and therefore increasing the supercooling point (SCP) and the cold hardiness. We here studied physiological plasticity in cold tolerance in Ophraella communa LeSage (Coleoptera: Chrysomelidae), a potential biological control agent of an invasive plant, the common ragweed, Ambrosia artemisiifolia L. (Asteraceae). Pupae of O. communa were collected from June to October, and the water and glycerol contents and the SCP of emerging adults were assessed. We found that SCP, water, and glycerol contents of beetles fluctuated significantly with season. Glycerol content of males and females increased with decreasing temperature between July and October, and glycerol content reached a maximum in October in the field. The lowest SCP was observed in adults in October prior to overwintering, and the highest SCP was evident in the summer population in July. Thus, cold hardiness of the beetles in the autumn population was significantly higher than in the summer population. We therefore conclude that cold tolerance, via changes in the relative composition of their body fluids and fats, is a plastic trait that can be influenced by fluctuations in abiotic factors (e.g., temperature) throughout the breeding season of the insect.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Fang Hao Wan

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Ambrosia artemisiifolia (weed)
Ophraella communa (weed bioagent)	Ambrosia artemisiifolia (weed)