Ability of Spalangia endius (Hymenoptera: Pteromalidae) to Parasitize Bactrocera dorsalis (Diptera: Tephritidae) after Switching Hosts

摘要

Bactocera dorsalis is an insect pest that causes substantial losses to fruit crops. It can be potentially controlled by the parasitoid wasp, Spalangiaendius Walker (Hymenoptera: Pteromalidae). S. endius is also used to control Musca domestica and is commercially produced. We studied the parasitism capacity of S. endius as a pupal parasite of Bactocera dorsalis after switching hosts. We mass-reared S. endius for more than 50 generations on M. domestica, and then allowed them to parasitize B. dorsalis to study the parasitism capacity of S. endius. More M. domestica were parasitized than B. dorsalis at different host densities. The S. endius colony, which was reared on M. domestica can be used to control B. dorsalis at a low density of B. dorsalis. The parasitism capacity of S. endius could be improved. The result showed that parasitoid-pest ratio should be 1:25 in order to maintain a relatively stable parasitism rate for controlling B. dorsalis. The rate of S. endius parasitizing B. dorsalis was decreased by parasitoid age. These results will help to optimize the use of S. endius, reared on M. domestica, for control of B. dorsalis.