Different species of stored-grain pest prey alter the demographic parameters of the predator Cheyletus malaccensis (Acari: Cheyletidae)

Abstract

Cheyletus malaccensis (Oudemans) is a predatory mite that can effectively control stored-grain pests and is a promising biological control agent in China. To promote the application of predatory mites to control stored-grain pests, the selection of stored-grain pest prey by C. malaccensis during large-scale feeding and population establishment needs to be studied. Therefore, we studied the life table parameters of C. malaccensis when fed five different prey species. Predator bodies were yellowish when consuming Aleuroglyphus ovatus and Carpoglyphus lactis, blackish when feeding on Lasioderma serricorne eggs, and brown spots appeared when feeding on Cryptolestes pusillus eggs. C. malaccensis completed its life cycle on each of the five types of prey. The effects of prey on C. malaccensis population reproduction were in the order, from greatest to least, C. lactis, A. ovatus, L. serricorne eggs, Rhyzopertha dominica eggs, and C. pusillus eggs. The highest fecundity (369.3 eggs per female) of C. malaccensis was recorded with the prey C. lactis, which was associated with an intrinsic rate of increase of 0.2417 day⁻¹. According to nutrient analyses, high sugar and protein levels in prey might have restricted the growth of C. malaccensis. The study data support the conclusion that C. lactis can serve as alternative prey to support population increase of C. malaccensis. Effective populations of C. malaccensis can also established by feeding on the eggs of stored-grain pests. The information in this study will contribute to the development of effective biological control strategies for managing stored-grain pests.