ARS | Publication request: Eugregarines reduce susceptibility of the hide beetle, Dermestes maculatus, to apicomplexan pathogens and retard larval development

Submitted to: Journal of Invertebrate Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 17, 2012
Publication Date: July 26, 2012
Citation: Lord, J.C., Omoto, C.K. 2012. Eugregarines reduce susceptibility of the hide beetle, Dermestes maculatus, to apicomplexan pathogens and retard larval development. Journal of Invertebrate Pathology. 111(2): 186-188. http://dx.doi.org/10.1016/j.jip.2012.07.007.

Interpretive Summary: Insect pathogens and microbial insecticides offer natural pest control and safe alternatives to chemical insecticides, but their impacts are limited. In experiments with hide beetles, which are emerging as pests of a variety of stored commodities, we discovered that nearly ubiquitous gut-inhabiting organisms of insects have two countervailing effects. They have a small retardant effect on growth rate, but when infections are heavy they provide protection from some orally transmitted pathogens. Both effects are thought to be the result of obstruction of access to the gut wall. This research provides a basic understanding of a possible impediment to natural pest suppression and the use of microbial agents and will help to improve the arsenal of non-chemical approaches to control insect pests in stored commodities.

Technical Abstract: Eugregarines are abundant in a great diversity of invertebrates, and yet their relationships with their hosts are subject to controversy and confusion. We tested the effect of the eugregarine, Pyxinia crystalligera, on growth, development, and susceptibility to two Apicomplexa pathogens of the hide beetle, Dermestes maculatus. Heavy infection with eugregarines provided partial protection from pathogenic neogregarines, Mattesia trogodermae and Adelina mesnili. Infection with P. crystalligera caused lower weight in beetle larvae, but did not significantly retard pupation or adult emergence. Adelina mesnili infection of Coleoptera and M. trogodermae infection of D. maculatus are reported for the first time.