Infection by a symbiotic polydnavirus induces wasting and inhibits metamorphosis of the mothPseudoplusia includens

• DOI: 10.1242/jeb.030635
• Publication Date: 2009-08-28T17:29:07Z
• Authors: A. J. Pruijssers; P. Falabella; J. H. Eum; F. Pennacchio; M. R. Brown; M. R. Strand
• Keywords: Prothoracic gland; Ecdysteroid; Hemolymph

SUMMARY Insect pathogens and parasites often affect the growth development of their hosts, but understanding these processes is fragmentary. Among most species-rich important mortality agents insects are parasitoid wasps that carry symbiotic polydnaviruses (PDVs). Like many PDV-carrying wasps, Microplitis demolitor inhibits pupation its lepidopteran host, Pseudoplusia includens, by causing host hemolymph juvenile hormone (JH) titers to remain elevated preventing ecdysteroid from rising. Here we report alterations only occurred if P. includens was parasitized prior achieving critical weight, were fully mimicked infection with M. bracovirus (MdBV). Metabolic assays revealed MdBV pre-critical weight larvae caused a rapid persistent state hyperglycemia reduced nutrient stores. In vitro further indicated prothoracic glands infected remained in refractory release, whereas post-critical had little or no effect on release glands. Taken together, our results suggest causes metabolic physiology, which prevent weight. This turn endocrine events normally trigger metamorphosis.