D-USYS, Department of Environmental Systems Science, ETH Zürich, 8092 Zürich, Switzerland.
Swiss Federal Institute of Aquatic Science and Technology, Eawag, 8600 Dübendorf, Switzerland.
Proc Biol Sci. 2023 Oct 25;290(2009):20231642. doi: 10.1098/rspb.2023.1642. Epub 2023 Oct 18.
Parasitoids in the genus specialize on ant-tended aphids and have previously been reported to mimic the cuticular hydrocarbon (CHC) profiles of their aphid hosts to avoid detection by ants. However, the precise mechanisms that mediate reduced ant aggression toward spp. are not known, nor is it clear whether such mechanisms are broadly effective or specialized on particular aphid hosts. Here we explore the effects of wasp genotype and host environment on CHC profiles and ant aggression. Rearing asexual lines in different host aphid environments revealed effects of both wasp line and aphid host on wasp CHCs. However, variation in genotype and host affected different features of the CHC profile, with wasp genotype explaining most variation in linear and long-chain methyl alkanes, while aphid host environment primarily influenced short-chain methyl alkanes Subsequent behavioural experiments revealed no effects of host environment on ant aggression, but strong evidence for genotypic effects. The influence of genotypic variation on experienced ant aggression and relevant chemical traits is particularly relevant in light of recent evidence for genetic divergence among parasitoids collected from different aphid hosts.
专性寄生在蚂蚁饲养的蚜虫上的寄生蜂属，以前曾被报道模拟其蚜虫宿主的表皮碳氢化合物 (CHC) 谱，以避免被蚂蚁发现。然而，介导寄生蜂属减少蚂蚁攻击的确切机制尚不清楚，也不清楚这种机制是否广泛有效或专门针对特定的蚜虫宿主。在这里，我们探讨了黄蜂基因型和宿主环境对黄蜂 CHC 谱和蚂蚁攻击的影响。在不同的宿主蚜虫环境中饲养无性系黄蜂线，揭示了黄蜂线和蚜虫宿主对黄蜂 CHC 的影响。然而，基因型和宿主的变异影响了 CHC 谱的不同特征，黄蜂基因型解释了线性和长链甲基烷烃的大部分变异，而蚜虫宿主环境主要影响短链甲基烷烃。随后的行为实验表明，宿主环境对蚂蚁攻击没有影响，但有强烈的证据表明存在基因型效应。鉴于最近有证据表明从不同蚜虫宿主收集的寄生蜂属存在遗传分化，基因型变异对经历的蚂蚁攻击和相关化学特征的影响尤其重要。
