9: Can OMRI approved insecticides and cultural tactics interfere with the efficacy of natural enemies of Bemisia tabaci Biotype B in organic squash

Silverleaf whitefly, Bemisia tabaci MEAM1, is one of the most damaging pests affecting squash in Florida. Bemisia tabaci is known to damage plants not only by feeding on plants but also by transmitting cucurbit viruses and causing physiological disorders, such as squash sliverleaf symptoms. The organic squash growers have a more daunting task to control whitefly and have to rely on organic insecticides. There is limited information on the effectiveness of organic insecticides and their integration with natural enemies. We conducted several experiments to evaluate the effects of organic insecticides on predators (Delphastus catalinae and Amblyseius swirskii) and parasitoids of whiteflies, and to evaluate the role of cultural tactics such as the use of marigold and cowpea in attracting natural enemies in the squash field. The results showed that both PyGanic and M-Pede negatively affected D. catalinae when released up to 3 days after spray (DAS) and at 5 DAS there was no effect on the predator. Azera affects the survival of A. swirskii when compared with M-Pede and control. M-Pede did not appear to affect A. swirskii survival. Marigold and cowpea had positive effects on attracting more whitefly parasitoids in the squash field. Using the organic insecticides in combination with natural enemies and cultural tactics can be effective in controlling whitefly in organic squash.