Bacterial symbionts have been found in a wide range of insect taxa with a spectrum of effects, acting on such diverse areas as nutrition, reproduction and pathogen acquisition. A facultative bacterial symbiont has recently been characterized from the hindgut of one species of thrips, Frankliniella occidentalis (deVries et. al. 2001). These bacteria are newly acquired each generation by larvae from their environment, and can be found in every life stage examined thereafter. The potential role and importance of these bacteria in thrips’ guts has yet to be determined, but their prevalence suggests that some effect is likely. One possible process that these symbiotic bacteria could affect is pathogen acquisition. Select species of thrips, including F. occidentalis, serve as vectors for plant viruses in the genus Tospovirus. These viruses are acquired at the midgut by larval thrips only. The potential thus exists for bacterial symbionts and virions to interact within the thrips’ gut. Bacterial symbionts have been isolated from thrips, cultured in Luria-Bertoni (LB) media and identified through genetic techniques. Anti-idiotypic antibodies, which act as mimics of Tospovirus glycoproteins, were found to bind to specific bacterial proteins on Western blots. These results are intriguing and support further investigation of the possible interaction between symbiotic bacteria and virions in vivo. The role of these bacteria in thrips fitness, as well as their potential interactions with virus, including any roles they may play in the acquisition of Tospoviruses, will be discussed.
Species 1: Thysanoptera Thripidae Frankliniella occidentalis (western flower thrips)
Keywords: insect vector, plant virus
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA