Feeding Behaviour of the Mite Blattisocius mali on Eggs of the Fruit Flies Drosophila melanogaster and D. hydei

Abstract

Many predatory mites use insects for dispersal; however, their possible negative effects on insect hosts during transportation and on insect offspring while preying in the hosts’ habitats are still poorly understood. A recent study has revealed that the predatory mite Blattisocius mali can not only spread by means of drosophilid fruit flies but also feed on their bodies during dispersal. The aim of this study was to examine the capability of B. mali to prey upon the eggs of their fruit fly hosts and determine the effect of the egg’s age on the voracity of this predator. Drosophila melanogaster oviposited on agar media for 1 h and D. hydei for 8 or 16 h. During 10-h experiments with fifteen fly eggs per cage, a single female predator totally consumed on average 3.62 ± 0.673 “1-h” D. melanogaster eggs and 3.00 ± 0.612 “8-h” eggs of D. hydei, while it partially consumed 2.75 ± 0.586 and 3.00 ± 0.612 eggs of each fly species. In the experiments involving D. hydei, the predator totally destroyed a similar number of “8-h” and “16-h” eggs, but it partially consumed significantly more younger eggs than older eggs. Ethological observations showed that mites returned to some partially fed eggs, usually from the side where the first puncture was made, and only then did they consume them whole.

Preliminary Studies on the Predation of the Mite Blattisocius mali (Acari: Blattisociidae) on Various Life Stages of Spider Mite, Thrips and Fruit Fly

“…'Skierniewicki' in a glasshouse, while the two-spotted spider mite, T. urticae, was reared on plants of the common bean cv. 'Ferrari' in a growth chamber at 23 As in previous studies by Michalska et al [9,17], we used the flightless form of the fruit fly D. hydei, commercially distributed as a live pet food. The population of D. hydei was maintained on the standard fruit fly medium based on cornmeal, molasses, yeast and propionic acid in an incubator at 25 • C with a 12/12 (L/D) photoperiod.…”

“…All manipulations and observations were made under an Olympus SZX 12 dissecting All experiments were carried out for 24 h within an incubator at 23 • C, 70-75% RH and 16/8 h (L/D) photoperiod using one-day-starved B. mali females. For starvation, females were put singly into the glass cages and kept there for the next 24 h. Cages with starving mites were kept in a desiccator, which provided a humidity of 75-80% RH [9,17]. The desiccator was maintained in an incubator at 23 • C and with a 16/8 h (L/D) photoperiod.…”

“…All insects and mites were obtained from and maintained in the Section of Applied Entomology, Department of Plant Protection at Warsaw University of Life Sciences (WULS). Blattisocius mali was reared using a mixture of bran and various stages of the mould mite Tyrophagus putrescentiae (Schrank) fed on yeast, following Michalska et al [ 9 , 17 ]. The species of predatory mite was identified morphologically by Prof. D.J.…”

“…It belongs to Blattisociidae, a family of predatory mites recorded in soil and on plants, associated with insects, rodents and birds. Species of the genus Blattisocius Keegan are a distinctive group that commonly inhabit storage facilities and feed on mites and insect eggs [ 8 , 9 ]. Although generally regarded as edaphic, they can visit plants; for example, B. dendriticus Berlese has been noted on the leaves of lychee [ 10 ], leaves/twigs/flowers of some citrus trees [ 11 ] and leaflets of strawberries [ 3 ].…”

“…The presence of this predator on plants suggests that it may also prey upon herbivorous insects and mites. Interestingly, recent studies on Drosophila melanogaster Meigen and D. hydei Sturtevant have shown that B. mali females can not only disperse by means of drosophilid fruit flies but also feed on their bodies during transportation, and they may also prey on their eggs after disembarkment [ 9 , 17 ]. As predatory mites transported by insects can prey upon the juvenile stages of their carriers, mostly eggs and larvae [ 18 , 19 , 20 ], it was suspected that B. mali may also feed on both the eggs and larvae of drosophilids.…”