| Egg parasitoids of the genus Trichogramma are widely utlized in biological control against Lepidopterous pests. Trichogramma chilonis Ishii were studied in this paper, which have been widely and deeply researched in China, focusing on evaluation about the influence of naturally environmental factors on the development and reproduction etc. The main results were summarized as follows:1 Effects of heat shock on the differet stage of the laboratory population of T. chilonisIn this paper, the experiment was carried out, which had close relationship to the effects of heat stress on the development,survival and reproduction of laboratory population of T. chilonis which reared on Corcyra cephalonica eggs , larval stage and treatment time. The results showed that heat stress(30℃～42℃)had little impact to generation development period of T. chilonis. Heat treatment could prolong the time of adult eclosion and also, it was longer from 6h to 24 h than that of CK. The favorable temperature and longevity for adults were 7.67d and 26℃respectively. The intrinsic rate of natural increase(rm) and net reproduction rater(R0) of them were 0.47 and 64.7 respectively. Because the adults supplied with nutrition may lengthen the life and enhances its tolerance to the high temperature .However, the extreme temperatures greatly restricted population increase of T.chilonis,especially at 42℃.At this temperature, the survival rate of egg , which were treated after 6 hours, was 4.3% only. the female wasps life span < 2d and there was failed fecundity. the survival rate was 26.5% under 8h treatment at 42℃on larva stage.The pupa were treated by heat stress under 8 h at 42℃failed to emergence.The tolerance order of high temperature on difference development stages separatly: pupa>adult>larva>egg.For the progeny generation,the tendency after the heat stress of adaptability to be enhanced by high temperature environment, but its tolerance whether does streng then waits fou further studies.2 Effects of heat stress on the functional response of T. chilonisIn this paper , it is reported that the functional response of T. chilonis which reared on Corcyra cephalonica (Staiuton) eggs at differently high temperature and treatment time. There were simulated with the Holling(Ⅱ)model. At different heat stress the differentiations of parasitic functional response were obvious, the Maximal preying number was 159.2 at4h treatment at 30℃.The rate of successful attack and parasitic rate were higher by heat stress under 4h treatment at 30℃, 2h treatment at 33℃,2h treatment at 36℃and 2h treatment at 39℃.The results indicated that heat stress might be a important potential predator for the suppressing parasitic. The parasitic has been restricted along with temperature increasing and treatment prolong.3 Acclimation of heat stress on T. chilonisThe proper temperature of T. chilonis is 26℃. Breeding by 34℃and 36℃heat stress, the female wasps lay eggs has increased, but for a long period of heat stress and not to be so long-term heat resistance enhance productivity.Biological characteristics, such as parasitism, emergence, reproduction, mean lifetime, parasitism,parasites in single host, et al., were used to evaluate the quality of selected strains of T. chilonis. The percentage of parasitism was, for judging the quality of the strain, recognized as the most important evaluation criterion, results of which showed that the selected strain of T. chilonis(6) was as good as the contrast (original strain).4 The comparison of the adaptability and ability of control target pestsIn greenhouse conditions in Turpan, Xinjiang, the investigation was been conducted on the difference of the adaptability and ability of control target pests between T.chilonis with domestication under heat shock and the normal population without heat shock.. The results showed that the longest distance that the wasps of T. chilonis spread from the release point was 10m, and the most of them were distributed within the 1～4m , a small number of individuals did their work ranged from 6m to 8m long. Domestication of the T. chilonis have higher adaptability and ability of control target pests than those of the normal wasps without domestication.
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