Alvarez-Baca Jeniffer K, Montealegre Xiomara, Alfaro-Tapia Armando, Zepeda-Paulo Francisca, Van Baaren Joan, Lavandero Blas, Le Lann Cécile
Laboratorio de Control Biológico, Instituto de Ciencias Biológicas, Universidad de Talca, Talca 3460000, Chile.
ECOBIO (Écosystèmes, Biodiversité, Évolution)-UMR 6553, Université de Rennes 1, CNRS, 6553 Rennes, France.
Insects. 2023 Mar 15;14(3):288. doi: 10.3390/insects14030288.
By increasing plant diversity in agroecosystems, it has been proposed that one can enhance and stabilize ecosystem functioning by increasing natural enemies' diversity. Food web structure determines ecosystem functioning as species at different trophic levels are linked in interacting networks. We compared the food web structure and composition of the aphid- parasitoid and aphid-hyperparasitoid networks in two differentially managed plum orchards: plums with inter-rows of oats as a cover crop (OCC) and plums with inter-rows of spontaneous vegetation (SV). We hypothesized that food web composition and structure vary between OCC and SV, with network specialization being higher in OCC and a more complex food web composition in SV treatment. We found a more complex food web composition with a higher species richness in SV compared to OCC. Quantitative food web metrics differed significantly among treatments showing a higher generality, vulnerability, interaction evenness, and linkage density in SV, while OCC presented a higher degree of specialization. Our results suggest that plant diversification can greatly influence the food web structure and composition, with bottom-up effects induced by plant and aphid hosts that might benefit parasitoids and provide a better understanding of the activity, abundance, and interactions between aphids, parasitoids, and hyperparasitoids in plum orchards.
通过增加农业生态系统中的植物多样性，有人提出可以通过增加天敌的多样性来增强和稳定生态系统功能。食物网结构决定生态系统功能，因为不同营养级的物种在相互作用的网络中相互联系。我们比较了两个管理方式不同的李子园中的蚜虫-寄生蜂和蚜虫-重寄生蜂网络的食物网结构和组成：种有燕麦作为间作作物的李子园（OCC）和种有自然植被的李子园（SV）。我们假设OCC和SV之间的食物网组成和结构会有所不同，OCC的网络专业化程度更高，而SV处理中的食物网组成更复杂。我们发现，与OCC相比，SV的食物网组成更复杂，物种丰富度更高。处理之间的定量食物网指标存在显著差异，表明SV具有更高的普遍性、脆弱性、相互作用均匀度和连接密度，而OCC具有更高的专业化程度。我们的结果表明，植物多样化会极大地影响食物网结构和组成，植物和蚜虫宿主产生的自下而上效应可能会使寄生蜂受益，并有助于更好地理解李子园中蚜虫、寄生蜂和重寄生蜂之间的活动、丰度和相互作用。
