Movement and dispersal of Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), as measured by an immunomarking technique; implications for the spread of huanglongbing

The Asian citrus psyllid (ACP) is an important pest of citrus as it vectors Candidatus Liberibacter asiaticus (Ca. Las), a bacterium that is a presumed causal agent of huanglongbing (HLB). Quantifying the dispersal range of ACP is critical to predict the potential spread of HLB within and between groves. Two studies were conducted that used an in situ immunomarking technique to track insect movement in the field. In the first experiment, we evaluated the dispersal range of ACP. The second investigation was conducted to determine the impact of abandoned citrus plots, in terms of ACP infestation and HLB infection, on nearby commercial groves. In both studies, crude food protein was sprayed in the field to mark insects; traps were placed at known distances from the marked area for the purpose of capturing marked insects; and captured ACP were subjected to an enzyme-linked immunosorbent assay (ELISA) to determine the presence of the protein mark. Our results indicate that 1) ACP adults can move at least 2000 meters within 11 days, 2) peak movement is seasonally variable with a majority of the movement occurring during the summer months, and 3) ACP move from abandoned groves into nearby managed groves. PCR analysis confirmed 1) the presence of Ca. Las in both abandoned and managed groves, and 2) ACP that are harboring Ca. Las move from abandoned groves into managed groves.