Temperature alters host suitability for parasitoid development through direct and indirect pathways. Direct effects depend on ambient temperatures experienced by a single host individual during its lifetime. Indirect effects (or parental effects) occur when thermal conditions met by a host parental generation affect the way its offspring will interact with parasitoids. Using the complex involving eggs of the moth Lobesia botrana as hosts for the parasitoid Trichogramma cacoeciae, we developed an experimental design to disentangle the effects of (1) host parental temperature (temperature at which the host parental generation developed and laid host eggs) and (2) host offspring temperature (temperature at which host eggs were incubated following parasitism, i.e. direct thermal effects) on this interaction. The host parental generation was impacted by temperature experienced during its development: L. botrana females exposed to warmer conditions displayed a lower pupal mass but laid more host eggs over a 12-h period. Host parental temperature also affected the outcomes of the interaction. Trichogramma cacoeciae exhibited lower emergence rates but higher hind tibia length on emergence from eggs laid under warm conditions, even if they were themselves exposed to cooler temperatures. Such indirect thermal effects might arise from a low nutritional quality and/or a high immunity of host eggs laid in warm conditions. By contrast with host parental temperature, offspring temperature (direct thermal effects) did not significantly affect the outcomes of the interaction. This work emphasises the importance of accounting for parental thermal effects to predict the future of trophic dynamics under global warming scenarios.

中文翻译：

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您来自何处：温度通过父母效应影响宿主-寄生虫的相互作用。

温度通过直接和间接途径改变了宿主对寄生虫发育的适应性。直接影响取决于单个宿主个体一生中所经历的环境温度。当宿主亲代产生的热条件影响其后代与寄生虫相互作用的方式时，就会发生间接效应（或父母效应）。我们使用涉及蛾蛾卵的复合物作为寄生性拟南芥（Trichogramma cacoeciae）的寄主，开发了一种实验设计，以消除以下因素的影响：（1）寄主亲代温度（寄主亲代发育并产下寄主卵的温度）和（ 2）宿主后代温度（寄生后即直接热效应，宿主卵孵化的温度）。寄主的亲代受到发育过程中温度的影响：暴露于较温暖条件下的博氏乳杆菌雌性displayed质量较低，但在12小时内产下更多的寄主卵。寄主父母的体温也影响了互动的结果。即使在温暖的条件下产下的卵出壳，毛细线虫的出苗率也较低，但胫后肢的长度却较高。这种间接的热效应可能是由于营养质量低和/或在温暖条件下产卵的宿主免疫力高所致。与寄主父母的体温相反，后代温度（直接的热效应）并未显着影响相互作用的结果。