GENETIC VARIATION AMONG DROSOPHILA MELANOGASTER ISOFEMALE LINES INFLUENCES ENCAPSULATION ABILITY OF THE PARASITOID ASOBARA TABIDA

One of the most important factors which affect the outcome of the host-parasite interactions is the genetic variation in particular those of the host. The aim of this study was to test the effect of variation within Drosophila melanogaster population on the encapsulation ability against the parasitoid Asobara tabida. To this end, nine isofemale lines of D. melanogaster which represent different levels of encapsulation ability were used. The encapsulation ability and its related parameters such as infestation, avoidance, and parasitism success and super-parasitism rates were assessed following oviposition. Larval weight, protein contents and phenoloxidase in extremes and intermediate lines, were investigated. The variation among D. melanogaster lines influenced encapsulation, avoidance, parasitism and superparasitism rates. Upon emergence, low success of the parasitoid associated with high mortality rates were observed in the representative lines. Although parasitized larvae may suffer from weight loss, they could survive based on mounting effective immune response. Parasitism of A. tabida in the Drosophila larvae induced high phenoloxidsae activity, particularily in the resistant ones refelecting their immune competency. In sum, the variation in encapsulation ability among isofemale lines demonstrates high underlying genetic variation. The data might help to design successful biological control programs and to facilitate interpretation of a similar interaction of other host-parasite model systems.