Open access publications in the SLU publication database

Abstract

An ecological guild of Tephritidae fruit flies exploits cucurbit vegetable fruits, tremendously reducing their production worldwide. Knowledge of the composition of the guild of infesting flies in the field and information on their natural enemy species, might improve pest management strategies. Our aim was therefore to identify Tephritidae species infesting the watermelon Citrullus lanatus (Thunb.) Matsum. & Nakai in the Republic of Benin. Morphological and molecular identification of parasitoid species present in the field collections was also done. Infested watermelons were sampled in one of the main watermelonproduction areas in the country. Adult tephritid flies emerging from watermelons were identified as Dacus bivittatus (Bigot), D. ciliatus Loew, D. punctatifrons Karsch, D. vertebratus Bezzi, Zeugodacus cucurbitae (Coquillet), and Ceratitis cosyra (Walker). In this study period, D. vertebratus was consistently the most abundant species emerging from watermelon. Dacus ciliatus was the second most common species followed by Z. cucurbitae. The number of emerging fruit flies per kilogram of watermelon varied with collection date and month, and was most variable for D. vertebratus. Parasitism in the fruit flies was 1.6 ± 6.4% and occurred through one wasp species that was identified as Psyttalia phaeostigma Wilkinson (Hymenoptera: Braconidae). This solitary parasitoid is closely related to other members of the P. concolor species complex, some of which are used in biological control. Problems associated with identifying Psyttalia species and possibility of using this wasp as a biological control agent against tephritid flies were discussed.