Objective  Adaptability to environmental variations of Leptocybe invase Fisher et LaSalle for growth and survival was investigated based on the physiological mechanisms of the pest in dealing with the adverse conditions.

  Methods   Geography-, temperature-, and host-specific morphological indicators, respiratory intensity, and activities of protective enzymes (such as, superoxide dismutase, catalase, peroxidase) and detoxification enzymes (such as, acetylcholinesterase, carboxylesterase, glutathione-S-transferase, polyphenol oxidase) of the insect were analyzed.

  Results  The morphological indicators of L. invase were inversely correlated to the latitude of the area it lived in. Its respiratory intensity and protective enzyme activity were relatively stable between 20 ℃ and 30 ℃. However, a surrounding temperature beyond 30 ℃ significantly raised the respiration rate and reduced the protective enzyme activity, while below 20 ℃ significantly decreased both. The diet also induced morphological differentiations in the insect. For instance, and the activities of 4 detoxification enzymes (acetylcholinesterase, carboxylesterase, glutathione-S-transferase, and polyphenol oxidase) were higher in the insects fed on DH201-2 (Eucalyptus grandis×E. tereticornis) than those on E. exserta.

  Conclusion  L. invase found in areas of lower latitude were smaller in body size than those of higher latitude. They thrived between 20℃ and 30℃. And the host plants on which they infested affected their morphology as well as the detoxification enzymes in the insect.