Identifying natural enemies of the Lebbeck mealybug, Nipaecoccus viridis Newstead (Hemiptera: Pseudococcidae), through molecular gut content analysis, and the impact of ant-mealybug mutualism on their diversity

The Lebbeck mealybug, Nipaecoccus viridis Newstead has recently established in Florida citrus. Due to routine application of broad-spectrum insecticides for management of the citrus greening vector, there has been a visible reduction in natural enemy populations. It is likely that this has allowed N. viridis to attain key pest status in Florida citrus groves. The goal of this research is to investigate the natural enemies present and feeding on N. viridis in Florida citrus, as well as the impact of ant-mealybug mutualism on natural enemy diversity. N. viridis specific primers were designed based on the cytochrome oxidase-I (COI) gene for use in molecular gut content analysis of potential predators by PCR. Random samples of potential predators were collected from N. viridis infested citrus groves by D-Vac methods. Individuals which show amplification of N. viridis DNA may be candidates for use as conservation biological control agents. Species richness and abundance are recorded for vacuum samples collected on infested trees both with and without an ant exclusion treatment. Preliminary species identification has shown that the presence of ants is tightly correlated with both lower richness and abundance of potential N. viridis predators, suggesting ant management may be a necessary component of a realized biological control program.