Submitted to: Crop Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/5/2010
Publication Date: 6/11/2010
Citation: Simmons, A.M., Kousik, C.S., Levi, A. 2010. Combining Reflective Mulch and Host Plant Resistance for Sweetpotato Whitefly (Hemiptera: Aleyrodidae) Management in Watermelon. Crop Protection. 29:898-902. Interpretive Summary: Whiteflies are important pests of watermelon. They cause damage when they feed, and they can infect the plant with problem viruses. A study was conducted on the use of reflective mulch and plant resistance for the management of the B-strain sweetpotato whitefly (also called silverleaf whitefly) in watermelon. The reflective plastic mulch was more effective in controlling the whitefly pest as compared with a standard black plastic mulch. Also, whitefly numbers were reduced by two resistant wild relatives of watermelon as compared with a common watermelon variety. Moreover, the results suggest that the reflective mulch does not hinder the populations of a whitefly predator (a lady beetle) or a whitefly parasite (a wasp). These findings suggest that using a combination of reflective mulch and resistant plants can suppress whitefly infestations and viral infections. This information may be of particular importance for the fast-growing organic vegetable production industry.
Technical Abstract: A study was conducted to evaluate the use of reflective mulch and host plant resistance for the management of the B-biotype sweetpotato whitefly, Bemisia tabaci (Gennadius), in watermelon [Citrullus lanatus var. lanatus (Thunberg) Matsum & Nakai]. Whitefly abundance data were collected under both greenhouse and field conditions. Consistently, a reflective plastic mulch (silver on black) treatment resulted in a lower incidence of whiteflies as compared with a standard black plastic mulch treatment. Moreover, whitefly populations were reduced by two resistant genotypes [PI 386015 and PI 386024; both C. colocynthis (L.) Schrad] as compared with a common watermelon cultivar. There was no interaction among the factors examined in the field, which suggests an additive effect of the treatments. The overall capture of adult whiteflies on yellow sticky traps was low during each of three field seasons. No effect of mulch color was observed for Delphastus catalinae (Horn), a whitefly predator, or for an Eretmocerus sp. whitefly parasitoid in caged trials, which suggests no adverse effect on these natural enemies when using reflective mulch. These results suggest that a combination of using reflective mulch and host plant resistance can additively suppress whitefly infestations and viral infections, which have particular importance to the fast-growing organic vegetable production industry.