Plant defence to sequential attack is adapted to prevalent herbivores

Plants have evolved plastic defence strategies to deal with uncertainty of when, by which species and in which order attack by herbivores will take place. However, the responses to current herbivore attack may come with a cost of compromising resistance to other, later arriving herbivores. Due to antagonistic cross-talk between physiological regulation of plant resistance to phloem-feeding and leaf-chewing herbivores, the feeding guild of the initial herbivore is considered to be the primary factor determining whether resistance to subsequent attack is compromised. We show that, by investigating 90 pair-wise insect-herbivore interactions among ten different herbivore species, resistance of the annual plant Brassica nigra to a later arriving herbivore species is not explained by feeding guild of the initial attacker. Instead, the prevalence of herbivore species that arrive on induced plants as approximated by three years of season-long insect community assessments in the field explained ...

植物已演化出可塑性防御策略（plastic defence strategies），以应对植食性昆虫取食的时间、攻击者物种以及取食顺序的不确定性。然而，针对当前植食性昆虫取食的防御响应，往往会以削弱对后续到来的其他植食性昆虫的抗性为代价。由于植物针对韧皮部取食型（phloem-feeding）与叶片咀嚼型（leaf-chewing）植食性昆虫的抗性生理调控存在拮抗信号交叉对话（antagonistic cross-talk），初始植食者的取食功能群（feeding guild）被认为是决定后续取食攻击抗性是否被削弱的核心因素。本研究通过对10种不同植食性昆虫间的90组两两互作开展调查，发现一年生植物黑芥（Brassica nigra）对后续到来的植食性昆虫的抗性，并非由初始攻击者的取食功能群所决定。取而代之的是，通过田间三年全季节昆虫群落调查所估算的、在诱导防御植株上出现的植食性昆虫物种的发生频度，解释了……