Management of silverleaf whiteflies by means of reduced-risk insecticides

Florida is among the largest producers of squash, Cucurbita pepo (Cucurbitaceae), with a value of over 45 million USD and accounting for over 19% of all U.S. production in 2021. The greatest threat to squash production in Florida is the silverleaf whitefly, Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae), which damages squash through physiological disorders and the transmission of viruses. An evaluation of reduced-risk insecticides was tested in a 2023 greenhouse study. Four treatments were evaluated on potted squash plants, including Sivanto Prime, Admire Pro, MBI-306, and an untreated control. In adults, results favored Sivanto Prime to exhibit greater whitefly population suppression when compared with Admire Pro, MBI-306, and the untreated control. Where that, Sivanto Prime had approximately one-fifth as many whiteflies as the control, one-fourth as many whiteflies as MBI-306, and one-third as many whiteflies as Admire Pro. The data also indicated that whitefly suppression is moderated by the interaction between treatment and life-stage. Where that, insecticidal treatments exhibited strong effects in adult life-stages and less of an effect on immature life-stages, such as with eggs and nymphs. Despite the lesser significance of insecticidal treatments against immature life-stages, Sivanto Prime consistently trended lower whitefly egg and nymphal counts than the untreated control, MBI-306, and Admire Pro, respectively.