Performance of Selected Insecticides Against the Sweetpotato Whitefly and Cotton Aphid

Abstract

Seven insecticides were evaluated in nine treatment combinations for efficacy against the sweetpotato whitefly (SPWF) and the cotton aphid (CA). Five different classes of chemistry were represented by these compounds, which were compared to an untreated check. The infestation was characterized as severe (> 300 SPWFs/sq. in.) and included a substantial number of CAs at the beginning of the evaluation ( >90 /leaf). Three applications were made in August after the onset of "stickiness." For SPWFs, three treatments compared favorably with the check, but only after three applications Orthene +Danitol, Capture alone, and Capture +Ovasyn. Intermediate control was achieved with Endosulfan +Ovasen. Rankingsfor CA control were dissimilar with Vvdate +Asana, Endosulfan +Ovasen, and Ovasen alone consistently performing better than the check. Vvdate alone, Endosulfan alone, and Orthene +Danitol were intermediate in CA control, but also significantly different from the check. Capture alone and Capture+Ovasyn which performed well for SPWF control was not efficacious against CAs. Indeed the two single pyrethroid treatments (Capture: Asana) failed to achieve any degree of CA control.