Gypsy moth herbivory induced volatiles and reduced parasite attachment to cranberry hosts

Interactions between species can have cascading effects that shape subsequent interactions. For example, herbivory can induce plant defenses that affect subsequent interactions with herbivores, pathogens, mycorrhizae, and pollinators. Parasitic plants are present in most ecosystems, and play important roles in structuring communities. However, the effects of host herbivory on parasitic plants, and the potential mechanisms underlying such effects, are not well known. We conducted a greenhouse study to ask whether gypsy moth (Lymantria dispar) damage, host cultivar, and their interaction affected preference of the stem parasite dodder (Cuscuta spp.) on cranberry hosts (Vaccinium macrocarpum). We then assessed the mechanisms that could underlie such effects by measuring induced changes in phytohormones and secondary compounds. We found that damage by gypsy moths delayed dodder attachment by approximately 0.3 days when dodder stems were added 2 days after damage, and reduced attachment by m...物种间的相互作用可产生级联效应，进而塑造后续的种间互作。例如，草食作用（herbivory）可诱导植物产生防御反应，进而影响后续与草食动物、病原菌、菌根（mycorrhizae）以及传粉者的相互作用。寄生植物广泛分布于多数生态系统中，在群落构建过程中发挥重要作用。然而，宿主草食作用对寄生植物的影响及其潜在作用机制，目前仍未得到充分阐明。本研究开展温室实验，旨在探究舞毒蛾（Lymantria dispar）取食为害、宿主品种及其交互作用是否会影响茎寄生植物菟丝子（Cuscuta spp.）对蔓越莓（Vaccinium macrocarpum）宿主的选择偏好。随后，我们通过检测植物激素（phytohormones）与次生代谢产物（secondary compounds）的诱导变化，解析上述效应可能的潜在作用机制。研究结果显示，当菟丝子茎段在宿主受舞毒蛾为害2天后接入时，舞毒蛾为害会使菟丝子的附着时间延迟约0.3天，并降低其附着率……