We investigated the fate of ingested Enterobacter (Pantoea) agglomerans and Klebsiella pneumoniae within adult Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), in a mass rearing facility. This examination revealed the establishment of both bacterial strains as biofilms within the adult intestines, on the apical end of developing and developed eggs, and throughout all subsequent life stages. The bacteria were detected in adults through two generations. Irradiation treatment for the sterile insect technique did not disrupt the vertical transmission of E. (P.) agglomerans or K. pneumoniae. This is the first demonstration of maternal spread of Enterobacter/ Pantoea spp. and Klebsiella spp. through populations of C. capitata. A mixed pattern of vertical and horizontal transmission of symbionts associated with tephritids may be one explanation for the difficulty in defining the symbiotic associations of tephritids.
The attraction of washed, medium-free cells of Pantoea (Enterobacter) agglomerans to wild, adult Rhagoletis mendax Curran, the blueberry maggot fly, was evaluated in managed blueberry fields in Maine. Attraction was evaluated using Pherocon AM and Ladd traps, each tested with or without washed bacterial cells. Field studies showed significant increases in fly captures on the Pherocon AM traps. Apple volatiles odors on Ladd traps seemed to cancel the effects of bacterial odors. Aerobic heterotrophic bacteria were isolated and identified from alimentary organs within wild R. mendax. Isolates indentified included P. agglomerans. Blueberries collected in the field were surveyed for the presence of P. agglomerans and blueberries containing blueberry maggot larvae and noninfested blueberries were analyzed for amino acid content. Maggot-infested blueberry contained twice the amino acid nitrogen than that of noninfested blueberry. P. agglomerans, like with other pest tephritids, seems to be a cosmopolite with blueberry maggot.
The use of Fourier Transform-Infrared Spectroscopy (FT-IR) in conjunction with Artificial Neural Network software NeuroDeveloper™ was examined for the rapid identification and classification of Listeria species and serotyping of Listeria monocytogenes. A spectral library was created for 245 strains of Listeria spp. to give a biochemical fingerprint from which identification of unknown samples were made. This technology was able to accurately distinguish the Listeria species with 99.03% accuracy. Eleven serotypes of Listeria monocytogenes including 1/2a, 1/2b, and 4b were identified with 96.58% accuracy. In addition, motile and non-motile forms of Listeria were used to create a more robust model for identification. FT-IR coupled with NeuroDeveloper™ appear to be a more accurate and economic choice for rapid identification of pathogenic Listeria spp. than current methods.
Investigations on microbial symbioses in Tephritidae have increased over the past 30 years owing to the potential use of these relationships in developing new control strategies for economically important fruit flies. Bactrocera oleae (Rossi)—the olive fruit fly—is a monophagous species strictly associated with the olive tree, and among all the tephritids, its symbionts are the most investigated. The bacterium Candidatus Erwinia dacicola is the major persistent resident endosymbiont in wild B. oleae populations. Its relationship with B. oleae has been investigated since being identified in 2005. This endosymbiont is vertically transmitted through generations from the female to the egg. It exists at every developmental stage, although it is more abundant in larvae and ovipositing females, and is necessary for both larvae and adults. Studying B. oleae–Ca. E. dacicola, or other B. oleae–microbe interactions, will allow us to develop modern biological control systems for area‐wide olive protection and set an example for similar programs in other important food crops. This review summarizes the information available on tephritid–microbe interactions and investigates relationships among fruit flies, bacteria and host plants; however, its focus is on B. oleae and its strict association with Ca. E. dacicola to promote environmentally friendly control strategies for area‐wide pest management.