The eggplant flea beetle, Epitrix fuscula, doesn't confine its predations to eggplants. It also enjoys munching on other solanaceous crops-like tomatoes-unless checked by insecticide applications and cultural practices. Growers would like to have an alternative method of reining in this nuisance pest that could reduce the amount of chemicals applied, especially in spring, when E. fuscula is most damaging. That goal led to the quest for an attractant compound, or pheromone, that would draw the insects to a central location where they could be dealt with efficiently. Host-feeding studies led to the identification of six volatile compounds emitted by male E. fuscula beetles while feeding on eggplant leaves. Researchers who synthesized them and monitored the sensory responses of both males and females found that two compounds stimulated the greatest electrical response, as measured in the test beetles' antennae. Field studies with eggplant showed that traps baited with the two active compounds attracted 500 percent more beetles than unbaited controls. Now the scientists are fine-tuning the ratio of the two compounds for maximum performance. Contact: Bruce W. Zilkowski, USDA-ARS Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Peoria, Illinois; phone (309) 681-6219.
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