LABORATORY AND FIELD EVALUATIONS OF IMIDACLOPRID AND THIAMETHOXAM AGAINST GWSS ON CITRUS AND GRAPES

• Author(s): Castle, Steven; Toscano, Nick; Bi, Frank;
• Abstract: The development of the neonicotinoid class of insecticides represents a powerful addition to our pest management capabilities. They are safer and more effective insecticides (Casida and Quistad, 1997) due to their lower mammalian toxicities, yet they exhibit higher toxicities against target insects. This permits their use at comparatively low rates and helps to limit environmental contamination. As systemic insecticides, they are more target-specific than conventional broadcast insecticides. This is because soil-applied neonicotinoid insecticides are taken up by plant roots and translocated throughout a plant. Thus, their toxic activity is by and large restricted to plant-feeding insects only. With their putative lower impact on beneficial insects relative to conventional insecticides, the neonicotinoids should be good candidates for incorporation into IPM programs for glassy-winged sharpshooter. The potential of neonicotinoids to protect citrus and grapes and other perennial crops against glassy-winged sharpshooter is only beginning to be tested. Worldwide, imidacloprid has proven highly effective against a range of insects, but with especially strong performance against sap-feeding insects in both annual and perennial crops. The more recent products such as thiamethoxam and acetamiprid have also shown strong performance against homopterans and other taxa. For each of these insecticides, clearer understanding of their activities against targeted insect pests will lead to more proficient usage. The overriding goal of research addressed by this project is to better understand the activity of neonicotinoid insecticides against glassy-winged sharpshooter in citrus and grapes. Direct effects on GWSS such as mortality and anti-feedant over the course of a treatment application need to be quantified. These are in turn dependent on the uptake and distribution dynamics within a tree or grapevine over the effective period of the treatment application. Knowledge of the duration and quality of protection afforded to large and complex plants such as mature citrus trees or grapevines is essential to optimizing the performance of neonicotinoid insecticides.
• Publication Date: Dec 2001
• Journal: 2001 Pierce's Disease Research Symposium