Differential Parasitism by Cotesia plutellae (Kurdjumov) on Plutella xylostella (L.) in Artificially Infested Host Plants

The parasitic potential of Cotesia plutellae (Kurdjumov) on diamondback moth larva was studied under laboratory and field conditions. The results revealed that the parasitism under field conditions was 27% lower than the caged laboratory conditions. Cauliflower, cabbage and mustard plants were more attractive to the gravid females establishing 56%, 53% and 45% parasitism, respectively, compared to other tested host plants. These were followed by Brussels sprout and broccoli. Lowest level of parasitism was recorded in knol-khol and kale under both field and caged laboratory conditions. The role played by host plants, herbivore induced volatiles and larval byproducts as well as the phyllotaxy of host plants in sheltering the host larvae are implicated for the observed variation in parasitism and discussed in a tri-trophic context.