In adult males and females of the yellow mealworm, Tenebrio molitor L., held under a 12-hour-dark 12-hourlight photoperiod, susceptibility to methyl parathion is highest at the onset of both the light and dark phases, with greatest resistance occurring 3 hours after the dark phase begins. Combined data for beetles of the 2 sexes show that the mean mortality rate at the beginning of the dark phase was 83% and at the beginning of the light phase was 85%. The mean dropped to 26% at 3 hours into the dark phase. Even though the daily fluctuation patterns were similar for the sexes, a substantial difference was seen between the sexes in the susceptibility throughout the cycle. Females were found to be continuously less susceptible to the toxicant. Locomotor activity for each sex was monitored and found to occur exclusively during the dark period.

中文翻译：

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成年黄粉虫（鞘翅目：黄粉虫科）运动活动的昼夜节律和对甲基对硫磷的敏感性

在黄粉虫黄粉虫的成年雄性和雌性黄粉虫中，在 12 小时-暗 12 小时光周期下，对甲基对硫磷的敏感性在亮和暗阶段开始时最高，抵抗力最大 3黑暗阶段开始后数小时。两性甲虫的综合数据表明，黑暗阶段开始时的平均死亡率为 83%，而光明阶段开始时的平均死亡率为 85%。在进入黑暗阶段 3 小时后，平均值下降到 26%。尽管两性的每日波动模式相似，但在整个周期中，两性之间的易感性存在显着差异。发现女性对毒物的敏感性持续降低。监测每个性别的运动活动，发现它们只发生在黑暗时期。