Submitted to: Pest Management Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/29/2012
Publication Date: 12/10/2012
Citation: Leskey, T.C., Wright, S.E., Saguez, J., Vincent, C. 2012. Incidental contact with insecticides and fungicides on plum curculio, Conotrachelus nenuphar (Herbst), movement and mortality: implications for pest management. Pest Management Science. 69:464-470. Interpretive Summary: Plum curculio is a serious pest of tree fruit throughout much of eastern North America. In order to better monitor and manage this fruit-feeding insect, we developed a laboratory method for assessing the behavioral effects of exposure to dried pesticide residues on horizontal and vertical mobility as well as quantifying overall mortality. Pesticides evaluated included Asana, Avaunt, Calypso, Clutch, Guthion, Imidan, Nova, Penncozeb, Provado, and Rimon, and water as a control. We found that many newer generation insecticides, such as neonicotinoids, and an insect growth regulator had little impact on overall mobility and mortality based on a two-hour exposure interval. Within the context of a treated orchard, adults may be able to feed and lay eggs for a period of time prior to succumbing to pesticide exposure. Conversely, the pyrethroid material, Asana, had an immediate impact on mobility as adults moved significantly greater distances and at greater speeds. This material resulted in mortality rates similar to those of organophosphates. Asana, like most pyrethroids, is considered disruptive to natural enemies and therefore, should be used in only spatially precise and limited locations such as in baited trap trees, an effective attract-and-kill strategy for plum curculio.
Technical Abstract: Exposure to Guthion and Imidan also led to high rates of mortality, though the impact on movement was less pronounced. Exposure to the neonicotinoid compounds, Calypso, Clutch, and Provado, to the insect growth regulator, Rimon, and to the fungicides, Nova and Penncozeb, had no impact on mobility and resulted in little to no mortality. Exposure to Avaunt, either through contact or by feeding on treated fruit, also had no measurable impact on mobility and little impact on mortality. Our results indicate that in the context of a treated orchard, it is likely that a foraging plum curculio coming into contact with dried pesticide residues of 'reduced risk' materials will be able to feed and oviposit for a period of time prior to succumbing to toxicant exposure. However, Asana has the capability of rapidly incapacitating plum curculio and may be a good option for targeted, spatially limited, and precise management strategies.