Baseline Susceptibility ofBemisia tabaci, Biotype B (Hemiptera: Aleyrodidae) to Chlorantraniliprole in Southern Florida

Abstract

ABSTRACT Chlorantraniliprole 200 mg ai L-1 (Rynaxypyr® 200 SC) is the first xylem systemic insecticide in the new chemistry class, anthranilic diamides. A laboratory systemic bioassay using cut stems of cotton seedlings was developed to quantify the baseline susceptibility of the sweetpotato whitefly, Bemisia tabaci (Gennadius) biotype B, to chlorantraniliprole. Bioassays were conducted for a susceptible laboratory colony and for 11 field populations collected in 2008 and 2009 in Southern Florida. Baseline data of the susceptible colony (targeting first instar nymphs with initial exposure at the egg stage) for chlorantraniliprole in 2008 and 2009, revealed a pooled LC50 and slope values of 0.033 mg ai L-1 and 1.186, correspondingly. With the implementation of the stabilization period in the bioassay method in 2009, the susceptible colony generated LC50 and slope values of 0.182 mg ai L-1 and 0.972, respectively. LC50 and slope values of field collected populations (targeting nymphs as above) ranged from 0...