Suppression of Whiteflies, Bemisia tabaci (Hemiptera: Aleyrodidae) and Incidence of Cucurbit Leaf Crumple Virus, a Whitefly-transmitted Virus of Zucchini Squash New to Florida, with Mulches and Imidacloprid

The sweetpotato whitefly, Bemisia tabaci B biotype (Gennadius) (Homoptera: Aleyrodidae) also known as Bemisia argentifolii (Bellows and Perring) is a key pest in zucchini squash (Cucurbita pepo L.) causing both direct and indirect damage. A field experiment was conducted in the fall of 2005 and repeated in the fall of 2006 to investigate the effect of mulches alone or in combination with a reduced-risk insecticide, imidacloprid (Admire® 2F) on whiteflies and related problems in zucchini squash. UV-reflective mulch and the living mulch, buckwheat (Fagopyrum esculentum Moench), with and without imidacloprid, were evaluated in a randomized complete block design with 4 replications. White mulch (standard) was included as a control in the experiment. Mulches in combination with imidacloprid resulted in fewer whiteflies per leaf than those without imidacloprid in 2005 and 2006. More whiteflies were recorded on zucchini plants growing on white synthetic mulch than all other treatments in both years. In the 2006 growing season, these plants also showed the first symptoms of viral infection caused by Cucurbit leaf crumple virus (CuLCrV), a whitefly-transmitted geminivirus. Both living and reflective mulches were more effective than white mulch in reducing the densities of whiteflies and the incidence of CuLCrV on zucchini plants.