Surveillance of Ants and Mealybug Populations in Virginia Vineyards

Mealybugs (Hemiptera: Pseudococcidae) are one of the prevalent pests infesting wine grapes in the eastern United States. Their close association with ants (Hymenoptera: Formicidae) provides them protection against natural enemies. In this paper, we present our research on identification of mealybug species and ant genera around vineyard and the effect of the use of sugar dispensers on the populations of ants and mealybug around the vineyard and on fruit cluster infestations. Field trials were carried out in two commercial vineyards in Virginia, United States, with a history of mealybug infestations. The sugar dispensers with and without insecticide were deployed to control ant populations on the vineyard. Pseudococcus maritimus (Ehrhorn) and Ferrisia gilli Gullan were the two species of mealybugs recorded from both sites. Tetramorium Mayr, Lasius Fabricius, Solenopsis molesta (Say), Crematogaster Lund and Pheidole Westwood were some of the dominant ant genera found in close asso-ciation with mealybugs. Ant number remained low in the untreated check throughout the sampling season. Sugar dispensers having insecticide although had higher number of ants, the number started decreasing subsequently throughout the sampling season. Fruit cluster infestation was also higher in the untreated check lacking any sugar dispensers.