Effect of Fly Gut Bacteria Incorporated Adult Diets on the Fecundity and Longevity of Zeugodacus cucurbitae (Coq.) and Bactrocera dorsalis (Hendel) (Diptera:Tephritidae)

The Melon fly, Zeugodacus cucurbitae (Coq.) and Oriental fruit fly, Bactrocera dorsalis (Hendel) are agriculturally important tephritid fruit flies. The probiotic use of insect gut bacterial community known to have significant positive impact on the overall fitness of different tephritid fruit flies in support of Sterile Insect Technique (SIT). In the present study the influence of fly’s gut-bacteria enriched adult diets, i.e., Serratia and Erwinia spp. added protein and sugar diets and their corresponding controls were evaluated on the ovariole number, fecundity, and mortality of Z. cucurbitae and B. dorsalis. The experimental results showed that Erwinia sp. and Serratia spp. enriched protein diets have no significant effect on the ovariole number of Z. cucurbitae and B. dorsalis after 14 days of adult emergence compared to those fed on only protein diet. No egg production was also recorded for both the fly species fed on only sugar diet at this age. Whereas delayed ovarian development and egg production was observed in Z. cucurbitae and B. dorsalis on 24 and 29 days, respectively while fed on Serratia sp. enriched sugar diet. The response of Z. cucurbitae in terms of egg production to bacteria enriched sugar diet was greater than B. dorsalis. In laboratory small cage experiment the mean mortality of Z. cucurbitae and B. dorsalis fed on Erwinia sp. and Serratia sp. enriched sugar diets were higher than bacteria enriched protein diets. Protein fed flies survival longer than protein deprived i.e., only sugar fed flies. Almost similar results were observed under semi-field cage experiment.