Submitted to: Pest Management Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/26/2011
Publication Date: 7/11/2011
Citation: Simmons, A.M., Abd-Rabou, S. 2011. Populations of predators and parasitoids of Bemisia tabaci (Hemiptera: Aleyrodidae) after the application of eight biorational insecticides in vegetable crops. Pest Management Science. 67:1023-1028. DOI: 10.1002/ps.2155. Interpretive Summary: The sweetpotato whitefly is a major pest of vegetables and many other crops worldwide. It is common for growers to use insecticides to control this pest, but some insecticides can harm the beneficial organisms that attack whiteflies. Nine non-conventional insecticides (based on oil, plant derivatives, insect growth regulator and a fungus) were evaluated for their compatibility to six natural enemies of whiteflies. Populations of four predators (common green lacewing, eleven-spotted lady beetle, a mirid bug and pirate bug) and two groups of wasp parasites (Encarsia spp. and Eretmocerus spp) were evaluated in vegetable crops in grower fields in Egypt. In all experiments, Jojoba oil, Biovar and Neemix had the least effect on the natural enemies in comparison to the other insecticides. However, Actelic, Admiral, KZ oil, Mesrona oil, Mesrona oil + Sulfur, and Natural oil all were very harsh on the populations of the natural enemies. These results demonstrate that different non-conventional insecticides for whitefly control can have different effects on natural enemies in the field.
Technical Abstract: The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is an important pest of vegetables and many other crops worldwide. Some insecticides may be more compatible with natural enemies for whitefly management than others. Nine biorational insecticides (based on oil, plant derivatives, insect growth regulator and fungus) were evaluated in the field in Egypt for their influence on populations of six natural enemies of B. tabaci. Natural populations of two predators [Chrysoperla carnea Stephen (Neuroptera: Chrysopidae) and Orius spp. (Hemiptera: Anthocoridae)] and two parasitoids [Encarsia spp. and Eretmocerus spp. (Hymenoptera: Aphelinidae)] were evaluated in eggplant (Solanum melongena L.). In addition, populations resulting from mass releases of three predators [C. carnea, Coccinella undecimpunctata L. (Coleoptera: Coccinellidae) and Macrolophus caliginosus (Wagner) (Hemiptera: Miridae)] were evaluated in fields of cabbage (Brassica oleracea var. capitata L.), cucumber (Cucumis sativus L.), and squash (Cucurbita pepo L.). Regardless of crop or natural enemy, Jojoba oil, Biovar and Neemix had the least effect on the populations of the natural enemies, in comparison to the other insecticides during a 14 day evaluation period. Conversely, Actelic, Admiral, KZ oil, Mesrona oil, Mesrona oil + Sulfur, and Natural oil had a high detrimental effect on natural enemy populations. These results demonstrate the differential effects of biorational insecticides for whitefly control on natural enemies in the field.