Effect of prey density on functional and reproductive responses of the predatory mitePhytoseiulus longipes(Acari: Phytoseiidae)

Publisher Website
Google Scholar
Abstract
The functional and reproductive responses of the female phytoseiid mite, Phytoseiulus longipes Evans, to increasing density of different developmental stages of its prey, Tetranychus pacificus McGregor, on excised bean leaves, and to the egg stage of the prey on the whole plant were studied under laboratory conditions. Daily consumption and oviposition rates of adult females on excised leaves increased with increasing prey density up to a certain maximum prey number, above which a plateau resulted (type II response). No interference effects were observed between prey and predator, i.e., no domed response curve was obtained. Instantaneous rate of discovery and handling time were calculated for the adult female predator on different prey stages. The relationships between these 2 parameters with respect to the changes in prey size were also discussed. The functional and reproductive response curves on whole plants were both sigmoid (type III response).