Behavioral Responses of Cotesia vestalis (Haliday) (Hymenoptera: Braconidae) to Honey-Based Diets

Abstract

Perception of odors and orientation of parasitoids in the direction of food sources are essential for good performance. I investigated the olfactory and behavioral responses of naïve female Cotesia vestalis (Haliday), a larval parasitoid of the diamondback moth, Plutellaxylostella (L.) (Lepidoptera: Plutellidae),to honey and honey-beebread using Y-tube olfactometer. Moistened air was blown over the food sources to carry odor in choice tests and behavior of each tested parasitoid was observed inside the olfactometer for 10 min. The diet chosen was also documented in each case. The newly emerged (i.e., <24h old) parasitoids responded to odor sources by antennating and making a series of movements. Tested females chose honey-beebread more quickly and more often than honey, which itself was chosen significantly faster and more often than moistened air (Control). The homing behavior of the parasitoids (i.e., entrance into the odor chamber) occurred more quickly with honey-beebread compared to honey, and no female wasp entered the chamber containing air alone. The results obtained in this study suggest that honey-beebread is more attractive to C. vestalis. This is an indication that if incorporated into the rearing program of C. vestalis, beebread would not have an adverse effect on the detection and movement of parasitoids towards available diet