Acetobacter tropicalisIs a Major Symbiont of the Olive Fruit Fly (Bactrocera oleae)

Abstract

Following cultivation-dependent and -independent techniques, we investigated the microbiota associated withAssociations of insects with bacteria, protozoa, and fungi are complex and intimate, ranging from parasitism to mutualism, and may be extracellular or intracellular and may play a role in the nutrition, the physiology, or the reproduction of the insect host (10). Petri (1909 to 1910) described one of the first bacterial symbiotic associations in an insect species, the olive fly, Bactrocera (Dacus) oleae (31, 32).The olive fruit fly B. oleae is one of the major pests of the olive tree, strongly affecting olive production worldwide, especially in the Mediterranean area, where more than 90% of the world's olive tree cultivation takes place (24,27). Although there have been reports on the isolation of potentially effective Bacillus thuringiensis strains against B. oleae, olive fly control strategies remain almost exclusively based on insecticides, despite the awareness of a need for the use of more environmentally friendly control methods (29). Recently, new concepts are emerging, among which the symbiotic control approach is particularly noteworthy (4). This strategy includes the use of symbionts as vectors of antagonistic factors able to block the life cycle of the plant pathogen in the insect host or, alternatively, their use for the suppression of host natural populations (45). In any case, a prerequisite for developing a symbiotic control approach is the knowledge of the microbiota associated with the insect pest.The nature of the olive fruit fly-associated microbiota is controversial. The culturable bacterium Pseudomonas savastanoi has been suspected to be a mutualist of B. oleae for more than 50 years (6,17,22,25,32,33). In addition, traditional microbiological approaches have identified other bacteria of the genera Bacillus,

The Olive Fly Endosymbiont, “CandidatusErwinia dacicola,” Switches from an Intracellular Existence to an Extracellular Existence during Host Insect Development

“…"Ca. Erwinia dacicola" has also been found within adult olive flies in Italy (9,52) and Greece (29). The high frequency of association of "Ca.…”

“…A century later, Capuzzo et al used molecular techniques to identify a specific uncultivable bacterium, "Candidatus Erwinia dacicola," in Italian adult olive flies (9). Other studies have identified transient gammaproteobacterial species acquired during feeding (5,52), as well as the alphaproteobacteria Acetobacter tropicalis (29) and Asaia spp. (52), within the olive fly.…”

“…The interaction between the olive fly, Bactrocera oleae, and its digestive-system bacterial associates has been studied for more than a century (5,9,17,28,29,32,33,36,52,55,56), yet several important questions remain unanswered. Do all olive fly life stages have the same species of bacterial endosymbiont?…”

Give us the tools and we will do the job: symbiotic bacteria affect olive fly fitness in a diet-dependent fashion

“…The association extends via the egg and continues in the larval stage where bacteria heavily populate the four midgut caeca during the entire larval development within the olive fruit (Petri 1910;Stammer 1929;Mazzini & Vita 1981). Although recent studies have identified several species of bacteria in the digestive tract of wild olive flies (Kounatidis et al 2009), the most common and widespread of these is Candidatus Erwinia dacicola (Capuzzo et al 2005;Estes 2009;Estes et al 2009). …”

Molecular Evidence for Multiple Infections as Revealed by Typing of Asaia Bacterial Symbionts of Four Mosquito Species

“…In the last decade, several AAB were discovered in association with arthropods, as was Gluconobacter morbifer associated with Drosophila melanogaster (23) or Acetobacter tropicalis associated with the olive fruit fly Bactrocera oleae (17). AAB seem to play a role in the stimulation of the immune system and the protection of the host against pathogens (24).…”