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Submitted to: Sweetpotato Whitefly Progress Review Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 5/1/2000 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Replicated small-plot studies were continued in 1998 to test the effects of a new imidacloprid-like insecticide (NI-25, Rhone-Poulenc) on generalist predators and whitefly parasitoids in cotton. Treatments consisted of NI-25 at 0.05, 0.075 and 0.1 lb AI/A, pyriproxyfen (grower standard), and an untreated control. Insecticides were applied according to thresholds sand natural enemy populations were monitored weekly from May through September. Rates of parasitism were low (less than 12%) and there were no differences in % parasitism between any of the treatments and the untreated control on any sampling dates. Densities of predatory beetles were generally low and no treatment differences were detected on any sample date NI-25 significantly depressed populations of predaceous Heteroptera in comparison with the untreated control and pyriproxyfen on several sample dates and a decline in the density of spiders was detected on 1 sample date ein July. Overall, these results are consistent with findings in 1997 studies. Heteropteran predators are facultative plant-feeders and this may place them at higher risk for exposure to NI-25 given its systemic activity |
