Super-predation and intraguild interactions in a multi-predator-one-prey system alter the abundance and behaviour of green peach aphid (Hemiptera: Aphididae)

Abstract

AbstractThe dynamics of interactions amongst natural enemies are central to the investigation of insect pest ecology. Ternary and quaternary interactions between parasitoids and predators in the presence of entomophagous organisms are yet to be comprehensively explored. We investigated the performance of a clone of green peach aphid (Myzus persicae(Sulzer); Hemiptera: Aphididae), raised on savoy cabbage (Brassica oleraceaLinnaeus; Brassicaceae), under all possible combinations of: I) the parasitoidAphidius colemaniViereck (Hymenoptera: Braconidae); II) the predatorChrysoperla carnea(Stephens) (Neuroptera: Chrysopidae); III) the predatorAdalia bipunctata(Linnaeus) (Coleoptera: Coccinellidae); and IV) the spiderParasteatoda tepidariorum(Koch) (Araneae: Theridiidae). We demonstrate a considerably differential green peach aphid abundance, polyphenism, and fine-scale spatial distribution in response to the combination, number, and identity of the present enemy species and their interactions. Surprisingly, certain combinations led to thriving green peach aphid populations due to interference between enemies; whereas, other combinations resulted in tangible collective suppression of the population. At the frontier of agroecology and entomology, we provide fresh insights on the effects of conflict and synergy between natural enemies sharing a pest of a cash crop as prey, highlighting the consequences of the presence of a novel synanthropic spider, as a top predator, on pest regulation.