Effect of bacteria on nutritional status and reproductive success of the Mediterranean fruit fly Ceratitis capitata

Abstract

Mediterranean fruit flies ( Ceratitis capitata Wiedemann, Diptera: Tephritidae) harbor a community of diazotrophic bacteria in their digestive system. The present study aims to test the hypothesis that bacteria contribute to fly fitness by enhancing copulatory success and egg production in males and females, respectively. After eclosion, flies were fed a full diet containing peptides, sugar and minerals, or a sugar diet, lacking peptides. Subgroups from each diet were fed a mixture of the antibiotics ciprofloxacin and piperacillin. The presence of bacteria, food consumption, weight gain, lipid and protein levels, oviposition in females and copulatory success of males were quantified in the four groups. The antibiotic treatment effectively cleared the gut of bacteria. The relative amounts of food consumed (with or without antibiotics) are similar in all groups. The antibiotics do not inhibit feeding, and their ingestion does not affect dry weight or the amount of protein stored, yet females feeding on the full diet without antibiotics have increased lipid levels. Females fed the full diet produce significantly more eggs than females on the sugar diet, but the presence of bacteria does not affect numbers of eggs produced. However, in the absence of bacteria, the oviposition rate of nutritionally stressed females is significantly accelerated. The presence of bacteria in sugar fed males does not provide them with a mating advantage. Conversely, in males fed a full diet, the presence of bacteria is associated significantly with a shorter latency to mate. It is concluded that, because the bacterial community is present at all stages of the fly's life cycle, at least some species are effectively transmitted from parents to offspring, and removal of bacteria affects measurable physiological and behavioural parameters related to fitness, the association between bacteria and the medfly is mutualistic.

The dual oxidase gene BdDuox regulates the intestinal bacterial community homeostasis of Bactrocera dorsalis

“…A previous study has shown that Enterobacteriaceae were dominant intestinal commensal bacteria in the gut of B. dorsalis , as well as in several other tephritids, such as Dacus (Drew and Lloyd, 1991), Anastrepha (Kuzina et al, 2001) and Ceratitis (Behar et al, 2008). These bacteria may contribute to nitrogen fixation (Behar et al, 2005), pectinolysis (Behar et al, 2008), male copulatory success (Ben-Yosef et al, 2008) and may also have an indirect contribution to host fitness by preventing the establishment or proliferation of pathogenic bacteria (Behar et al, 2008). Members of the Leuconostoc genus ferment fructose (Ljungdahl, 1962), suggesting that these microbes may play a symbiotic role in promoting insect digestion of fruits or other plant materials (Corby-Harris et al, 2007).…”

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

“…A third diet contained sugar, minerals and NE amino acids as the sole source of amino nitrogen. Antibiotics (piperacillin, Fluka), which had previously been used effectively to suppress the gut bacterial population in the Mediterranean fruit fly (Ben-Yosef et al 2008a), were added to the diet of half of the females in each of the three groups in order to eliminate the bacterial component of the gut microbiota.…”

Gut microbiota influences female choice and fecundity in the nuptial gift-giving species, Drosophila subobscura (Diptera: Drosophilidae)

“…A similar study examining the fruit fl y C. capitata showed that removing the commensal gut bacteria results in no difference of fecundity but an increase in oviposition rate (Ben-Yosef et al, 2008). Although this effect is slightly different to the one we have shown in D. subobscura as overall fecundity is not shown to be different, it reaffi rms that bacteria must play an important part in post-mating female reproductive physiology and behaviour.…”

“…Individuals were either fed normally, and therefore had a "typical" gut bacterial content, or they were fed with antibiotic-supplemented food. Adding antibiotics to the rearing medium is a standard method of suppressing gut bacteria (Koukou et al, 2006;Ben-Yosef et al, 2008;Sharon et al, 2010;Lizé et al, 2014). However, in order to confi rm that our technique resulted in suppression of the gut microbiota, we analysed the bacterial content of the D. subobscura gut from both the normal and the streptomycin reared diets.…”