Interactions between the red imported fire ant, the citrus leafminer, and its parasitoid Ageniaspis citricola (Hymenoptera: Encyrtidae): laboratory and field evaluations

Interactions between the red imported fire ant [Solenopsis invicta (Hymenoptera: Formicidae)],the citrus leafminer [Phyllocnistis citrella (Lepidoptera: Gracillariidae)], and the citrus leafminerendoparasitoid Ageniaspis citricola (Hymenoptera: Encyrtidae) were investigated under laboratoryand field conditions in Florida. Previous studies had shown that S. invicta would selectivelyprey on brown citrus aphids (Toxoptera citricida ) parasitized by Lipolexis oregmae and Asian citruspsyllids (Diaphorina citri ) parasitized by Tamarixia radiata , which led us to question whetherS. invicta would selectively prey on citrus leafminer (CLM) larvae or eggs parasitized byA. citricola . In the laboratory trial, there was no significant difference between the type of CLMlarvae preyed on. However, higher predation was observed on parasitized CLM larvae reared onpotted plants in a citrus grove. A subsequent citrus grove test revealed slightly, although notsignificantly, lower levels of parasitism by A. citricola in trees to which ants had access becausepredation by ants was higher. However, predation by other predators in the trees to which antshad no access resulted in no significant differences in CLM densities in the two treatments. Thefield data provide, for the first time, the seasonal phenology of the CLM and its parasitoidA. citricola in the Indian River region of Florida in an unsprayed grapefruit block.