Trait-mediated indirect interactions: moose browsing increases sawfly fecundity through plant induced responses

1. Induced responses in plants, initiated by herbivory, create potential for trait-mediated indirect interactions among herbivores. Responses to an initial herbivore may change a number of plant traits that subsequently alter ecological processes with additional herbivores. Although common, indirect interactions between taxonomically distant herbivores, such as mammals and insects, are less studied than between taxonomically related species (i.e. insect-insect). In terms of mammal-insect interactions, effects on insect numbers (e.g. density) is relatively well studied, whereas effects on performance (e.g. fecundity) are rarely explored. Moreover, few studies have explored mammal-insect interactions on coniferous plants. 2. The aim of this study was to investigate the effect of mammalian induced responses on insect performance. We specifically investigated the effect of moose (Alces alces) browsing on Scots pine (Pinus sylvestris) and subsequent effects on sawfly (Neodiprion sertifer) p...1. 植物因植食作用触发的诱导响应，为不同植食者之间的性状介导间接相互作用提供了潜在可能。针对初始植食者的诱导响应可改变诸多植物性状，进而会改变后续其他植食者参与的生态过程。尽管这类间接相互作用较为普遍，但相较于分类学亲缘关系较近的物种间（如昆虫-昆虫）的相互作用，哺乳动物与昆虫这类分类学亲缘关系较远的植食者之间的间接相互作用，相关研究仍较为匮乏。就哺乳动物-昆虫的相互作用而言，现有研究对其影响昆虫种群数量（如种群密度）的效应已有较多探讨，但针对其对昆虫表现（如繁殖力）的影响则少有研究。此外，针对针叶植物上的哺乳动物-昆虫相互作用的相关研究更是寥寥无几。 2. 本研究旨在探究哺乳动物诱导的植物响应对昆虫表现的影响。本研究聚焦考察了驼鹿（Alces alces）啃食对欧洲赤松（Pinus sylvestris）的影响，及其对新松叶蜂（Neodiprion sertifer）产生的后续效应……