Inventory of parasitoids of Ceratitis cosyra and Bactrocera dorsalis (Diptera: Tephritidae), pests of several fruit species in the department of Borgou, Bénin

Abstract

Fruit flies (Diptera: Tephritidae) are widespread frugivorous pests of economic importance infesting some fruit species in Benin, such as Mangifera indica, Psidium guajava, Vitellaria paradoxa, Annona senegalensis and Sarcocephalus latifolius. The objective of this study was to obtain information on the parasitoids of Ceratitis cosyra and Bactrocera dorsalis. The study was conducted in four townships (Tchaourou, Parakou, N'Dali and Bembérékè) in the Department of Borgou, Benin, from April to October 2009. A total of 7270 fruits were collected from the five fruit species and the four districts, taken to the laboratory and placed on sand in gauzecovered containers to collect pupae and parasitoids. Pupae were collected every 5 days by sifting the sand. We obtained 54,171 pupae from which six fruit fly species emerged, the two dominant species being C. cosyra (69.7%) and B. dorsalis (11.8%). Seven species of parasitoids were collected; Fopius caudatus, Tetrastichus giffardianus, Pachycrepoïdeus vindemmiae, Fopius silvestri, Diachasmimorpha fullawayi, Psyttalia cosyrae and Psyttalia concolor. Fopius caudatus was the main parasitoid species collected in the study. Moreover, among the cultivated fruit species, M. indica (mango) had the highest fruit fly infestation rate (average of 32.2 pupae/kg fruit), while fruit flies from P. guajava (guava) were the most parasitized. Generally, the wild fruit species had more fruit fly infestation which was more parasitized than the cultivated species. (Texte intégral