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ARS Home » Southeast Area » Charleston, South Carolina » Vegetable Research » Research » Publications at this Location » Publication #333217

Research Project: Sustainable Approaches for Pest Management in Vegetable Crops

Location: Vegetable Research

Title: Effects of a foliar neem formulation on colonization and mortality of whiteflies (Hemiptera: Aleyrodidae) on collard plants

item KRZYZANIAK, DANA - Academic Magnet High School
item Simmons, Alvin
item SHEPARD, MERLE - Clemson University

Submitted to: Agricultural Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/4/2016
Publication Date: 11/7/2016
Citation: Krzyzaniak, D., Simmons, A.M., Shepard, M.B. 2016. Effects of a foliar neem formulation on colonization and mortality of whiteflies (Hemiptera: Aleyrodidae) on collard plants. Agricultural Sciences. 7:771-782. doi:10.4236/as.2016.711071.

Interpretive Summary: Whiteflies are major pests on many crops; they cause direct damage to plants from feeding and they cause indirect damage by transmitting plant viruses to plants. GOS Neem 7-Way is a botanical insecticide from seeds of the neem tree and is marketed for use in both organic and conventional crop production. A study was conducted to assess the utility of this insecticide as a management tool for whiteflies on collard plants. Spray application on leaves resulted in decreased populations; the spray repelled many of the adult whiteflies during the first day after treatment, and the spray was effective in it resulted in mortality of the whiteflies. The results demonstrates that this insecticide may be a useful tool for growers to use in a sustainable whitefly management program.

Technical Abstract: A study was conducted to determine the effects of foliar sprays of a selected neem (Azadirachta indica A. Juss) product (GOS Neem 7-Way) on colonization and development by the Middle-East Asia Minor-1 (= B-biotype sweetpotato whitefly) Bemisia tabaci (Gennadius) on collard (Brassica oleracea variety acephala de Condolle) plants. GOS Neem 7-Way is marketed for use in organic and conventional crop production. Caged choice, caged no-choice, and Y-tube olfactometer assays were conducted on oviposition, survival and adult behavioral response to plant treatment with 1.25% azadiractin. In the caged choice experiment, colonization by the whiteflies was reduced and fewer eggs were deposited on control plants (only treated with an adjuvant) as compared with neem-treated plants. Similarly, decreased numbers of adult whiteflies and reduced whitefly development were observed in the neem-treatment groups, as compared with the untreated control. Both horizontal and vertical-orientated Y-tube olfactometer assays provided complimentarily assessments that the azadiractin had a repellency effect on the adult whiteflies. However, the repellency effect dissipated within one day. Overall, the greatest benefit of the azadiractin treatment appears to have been on whitefly mortality. The findings may be useful in providing a more ecologically sound way to manage populations of the sweetpotato whitefly in organic vegetable production.