Wednesday, December 15, 2010
Grand Exhibit Hall (Town and Country Hotel and Convention Center)
Parasitism by the braconid was Cotesia flavipes affects the growth of Diatraea saccharalis larvae in a parasitoid dose-dependent fashion. Following parasitization of fifth-instar larvae, more heavily parasitized larvae grew larger compared to those containing fewer parasitoids due to an increase in host dry weight. The differences in host mass appeared to arise after oviposition. A dose-dependent enhancement of host dry weight would appear nutritionally beneficial for the parasitoids developing in more crowded hosts. The efficiencies of conversion of ingested and digested food to body mass and approximate digestibility of the diet ingested by host caterpillar did not vary with clutch size, although parasitoids took slightly longer to develop in the more heavily parasitized hosts. Larval parasitoids developing in the presence of many competitors weighed up to 50 % less than those developing in hosts with fewer endoparasitoids, although the weight of adult female parasitoids did not vary with was clutch size. The ratio of the parasitoid emergence to non-emerging decreased as parasitoid clutch size increased, with fewer or none emerging from very heavily parasitized host containing more than 100 parasitoids.