Desempenho do parasitóide Nasonia vitripennis (Walker) (Hymenoptera, Pteromalidae) utilizando como hospedeiro Cochliomyia macellaria (Fabricius) (Diptera, Calliphoridae), sob diferentes tempos de exposição

Abstract

The post-embryonic development, the productivity of the host pupae, the rate of parasitism and the sex ratio of Nasonia vitripennis reared in pupae of Cochliomyia macellaria were studied. Different exposition times were used: 24, 48, 72, 96 hours. Nulliparous females originating from the stock colony were individualized in test tubes covered with hydrophobic cotton and containing the host pupae. Each treatment was constituted by 10 replicates. After exposition, the hymenopterans were discarded and the host pupae were individualized in test tubes until the emergency of the adults of C. macellaria or N. vitripennis. Samples of host pupae not exposed to parasitism and receiving the same experimental treatment, were used as control. The parasitoids showed a slower development in relation to the increase exposition time. The 72 hours exposition was the one which enabled higher productivity. The sex ratio tended towards a deviation for the birth of females after 48 hour. The rate of parasitism increased up to 72 hours. The rate of dipteran's emergence showed a decrease until 72 hours.