Submitted to: Entomologia Experimentalis et Applicata
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/27/2005
Publication Date: 2/3/2006
Citation: Sivinski, J.M., Aluja, M., Holler, T. 2006. Food sources for adult Diachasmimorpha longicaudata, a parasitoid of tephritid fruit flies: effects on longevity and fecundity. Entomologia Experimentalis et Applicata. 118:193-202. Interpretive Summary: Tephritid fruit flies destroy fruits and vegetables, and cause export restrictions wherever they occur. One means of their control is to mass-rear and then release parasitoids in the field. The success of these parasitoids depends on their ability to survive following release, but little is known about what kinds of foods the adult insects require. Scientists at the USDA-ARS, Center for Medical, Agricultural and Veterinary Entomology (Gainesville, FL) in collaboration with colleagues from the Instituto de Ecologia (Xalapa, Veracruz, Mexico) studied candidate food sources for one commonly reared parasitoid and discovered that it feeds on fruit and fruit juices. This is a highly unusual food source for a parasitoid, but because it closely associated with fruit fly hosts it is likely to be common in nature. This means that additional food sources will probably not have to be placed artificially in the field during mass-release programs
Technical Abstract: We report the results of a study on the nutritional ecology of the widely distributed Indo-Australian braconid fruit fly parasitoid Diachasmimorpha longicaudata (Ashmead). Adults sustained life on diets of fruit juice/fruit pulp, hemipteran honeydew or extrafloral nectary secretions. Longevities on all these foods and fecundity on fruit juice were comparable to those achieved on the honey that is typically provided in mass-rearing programs. Certain of the flower species Bidens alba (L.), Spermacoce verticillata L., Lobularia maritima (L.) Desv., Brassica nigra (L.), Lantana camara L., their nectar or pollen, provided a diet that resulted in longer maximum life spans than controls given water alone. Those flowers that sustained D. longicaudata for greater periods of time were not unusually accessible to the relatively short-tongued hymenopteran (i.e., they did not have particularly short or wide corollas). Unlike some tephritid flies, the braconid did not feed on fresh bird feces or leaf-surface exudates. The capacity of D. longicaudata to feed upon wounded host-fruits of tephritid flies suggests that adult parasitoid food might be abundant in sites with high infestation of larval-hosts. Because both adult food and oviposition sites occur in the same locations separate forays to acquire one or the other would be unnecessary. We conclude that an inventory of adult foods might help target inundative releases of D. longicaudata and lead to improvements in diets used for mass-rearing.