Mortality of Rhagoletis species encountering pesticide-treated spheres (Diptera: Tephritidae)

Baited pesticide-treated biodegradable spheres were evaluated for their efficacy to control and monitor apple maggot, Rhagoletis pomonella (Walsh), and blueberry maggot, R. mendax Curran, flies. A Plexiglas pane treated with sprayable Tangle-Trap was found to be an effective technique for assessing the fate of Rhagoletis flies encountering treated spheres. Significantly more R. pomonella and R. mendax flies were captured on Plexiglas panes below pesticide-treated spheres compared with panes below nonpesticide-treated spheres. The mean time spent on pesticide-treated spheres was also significantly longer compared with nonpesticide-treated spheres. Monitoring traps (consisting of unbaited 9-cm-diameter red sticky spheres) placed within a 2-m radius of pesticide-treated spheres captured significantly fewer flies compared with traps placed at the same distance from nonpesticide-treated spheres. The results support the potential for using pesticide-treated spheres for control of R. pomonella and other Rhagoletis species.