Centre of Excellence in Biological Interactions Research, Department of Biological and Environmental Science, University of Jyväskylä Jyväskylä, Finland.
Evol Appl. 2013 Feb;6(2):313-23. doi: 10.1111/eva.12001. Epub 2012 Sep 7.
Adaptation to stressful environments is one important factor influencing species invasion success. Tolerance to one stress may be complicated by exposure to other stressors experienced by the preceding generations. We studied whether parental temperature stress affects tolerance to insecticide in the invasive Colorado potato beetle Leptinotarsa decemlineata. Field-collected pyrethroid-resistant beetles were reared under either stressful (17°C) or favourable (23°C) insecticide-free environments for three generations. Then, larvae were exposed to pyrethroid insecticides in common garden conditions (23°C). Beetles were in general tolerant to stress. The parental temperature stress alone affected beetles positively (increased adult weight) but it impaired their tolerance to insecticide exposure. In contrast, offspring from the favourable temperature regime showed compensatory weight gain in response to insecticide exposure. Our study emphasizes the potential of cross-generational effects modifying species stress tolerance. When resistant pest populations invade benign environments, a re-application of insecticides may enhance their performance via hormetic effects. In turn, opposite effects may arise if parental generations have been exposed to temperature stress. Thus, the outcome of management practices of invasive pest species is difficult to predict unless we also incorporate knowledge of the evolutionary and recent (preceding generations) stress history of the given populations into pest management.
适应充满压力的环境是影响物种入侵成功的一个重要因素。对一种压力的耐受性可能会因前几代经历的其他压力源而变得复杂。我们研究了父母的温度应激是否会影响入侵性科罗拉多马铃薯甲虫 Leptinotarsa decemlineata 对杀虫剂的耐受性。从野外收集的拟除虫菊酯抗性甲虫在无杀虫剂的有利（23°C）或不利（17°C）环境中分别饲养三代。然后，将幼虫在共同的花园条件（23°C）下暴露于拟除虫菊酯杀虫剂中。一般来说，甲虫对压力有一定的耐受性。单独的父母温度应激对甲虫有积极影响（增加成虫体重），但会损害它们对杀虫剂暴露的耐受性。相比之下，来自有利温度条件的后代在暴露于杀虫剂时会表现出代偿性的体重增加。我们的研究强调了跨代效应对物种压力耐受性的潜在影响。当抗药性害虫种群入侵良性环境时，杀虫剂的重新使用可能会通过赫米效应增强它们的表现。相反，如果父母代已经暴露在温度应激下，可能会产生相反的效果。因此，除非我们将给定种群的进化和近期（前几代）压力史知识纳入害虫管理，否则入侵性害虫物种的管理实践的结果是难以预测的。
