Intra-guild vs extra-guild prey: Effect on development, predation and preference ofTyphlodromus negeviSwirski and Amitai andTyphlodromips swirskii(Athias-Henriot) (Acari: Phytoseiidae)

Abstract

The relationships between the predatory mites, Typhlodromus negevi Swirski and Amitai and Typhlodromips swirskii (Athias-Henriot) (both Acari: Phytoseiidae), and their prey, tobacco whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) were investigated to determine the effects of predation on intra-guild or extra-guild prey and predator preference. Life cycle characteristics of both predatory mites were measured when fed eggs and larvae of the other predator species and compared to data obtained when the predators were fed whitefly eggs. In addition, choice tests were conducted to determine if the predators had a preference for different prey/stage or not.Typhlodromips swirskii appears to be an important intra-guild predator on T. negevi juveniles because of a high predation rate and a preference for T. negevi eggs (intra-guild prey) over whitefly eggs (extra-guild prey) when offer a choice test. Typhlodromus negevi is also an intra-guild predator of T. swirskii juveniles; it has a lower predation ...