松毛虫赤眼蜂是一种很好的生防因子，在防治苹果蠹蛾时具有很高的适用性。为提高耐低湿松毛虫赤眼蜂对苹果蠹蛾的控制效果，以苹果蠹蛾卵为寄主卵，通过赤眼蜂的寄生试验研究了寄主卵日龄和密度对耐低湿松毛虫赤眼蜂寄生效果的影响，完善甘肃地区田间赤眼蜂释放技术以减少生产成本。结果表明，松毛虫赤眼蜂对2日龄苹果蠹蛾卵有更好的寄生选择，当蜂卵比为1∶30时，寄生率最大，达82.22%。通过赤眼蜂和苹果蠹蛾卵的寄生选择关系，确定了最佳蜂卵比为1∶30，此比值下，雌蜂的单蜂寄生效能约为 26.50 粒/蜂，苹果蠹蛾卵的被寄生率约为70%，达到较好的寄生效果。经实验室长期耐低湿处理的松毛虫赤眼蜂能更好地适应不利的环境因子，其在西北干旱地区有更高的适用性。建议在田间使用时，可通过虫情监测判断苹果蠹蛾产卵时间和数量，然后可确定在苹果蠹蛾高峰产卵期48 h后释放赤眼蜂，且释放的蜂量应保持蜂卵比值约为1∶30。

Trichogramma dendrolimi is a good biocontrol factor, which has high applicability in controlling the Cydia pomonella. In order to improve the control efficiency of T. dendrolimi against C. pomonella, we selected T. dendrolimi through multiple generations under low humidity stress. This paper studied the effects of host egg age and density on the parasitism of T. dendrolimi tolerant to low humidity by using the eggs of C.pomonella as host eggs. The results showed that T.dendrolimi had better parasitism selection on 2-day eggs, and when the ratio of wasp and egg was 1∶30, the maximum parasitism rate was 82.22%. 1:30, the optimum ratio of wasp and egg, was determined by the parasitic selection relationship between T. dendrolimi and C. pomonella eggs. Under this ratio, the single parasitism efficiency of female wasps was about 26.50 eggs/per individual and the parasitism rate of C. pomonella eggs was about 70%, which showed ideal parasitism. T. dendrolimi treated with low humidity for a long time in the laboratory could better adapt to adverse environment, which had better applicability in northwestern arid regions. It is recommended that the laying time and number of C. pomonella can be judged by insect situation monitoring, and T. Dendrolimi can be released 48 h after the peak laying period of C. pomonella, and the number of wasps released should keep ratio of wasp and egg about 1∶30.

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兰州市人才创新创业项目(2018-RC-115)；甘肃省农业科学院农业科技创新中青年基金项目(2021GAAS49)。