An Attempt to Change Habitat Preference of a Parasitoid, Cotesia sesamiae (Hymenoptera: Braconidae), Through Artificial Selection

Insect parasitoids are under strong selective pressure to utilize available hosts, which could cause a parasitoid used as a biological control agent to extend its host range. We artificially selected for a change in habitat preference of the braconid parasitoid Cotesia sesamiae (Cameron), to test the potential for host range expansion. Cotesia sesamiae parasitizes stemborers of maize and sorghum and has potential as a biological control agent of many stemborers. We tested selection for increased attraction to sorghum (a favored plant) and to cabbage (a non-favored plant) through experiments carried out over 4 generations. No change in attraction to either plant was observed, suggesting that this parasitoid may not easily expand its host range through a change in habitat preference.