Pyrethroid Insecticide Efficacy Against Tobacco Budworm (Lepidoptera: Noctuidae) in North Carolina Flue-Cured Tobacco: Implications for Insecticide Resistance Management

Abstract

Foliar applications of 3 pyrethroid insecticides were made to flue-cured tobacco and compared with Bacillus thuringiensis Berliner (Bt) bait and sprays of acephate and spinosad for control of the tobacco budworm, Heliothis virescens (F.), in 2001, 2002, and 2003. Lambda-cyhalothrin, cyfluthrin, and bifenthrin provided significant control of tobacco budworm when compared with untreated checks in all 3 yrs; however, they were generally less efficacious than the other insecticides tested. The level of control among the pyrethroids differed significantly within years but was inconsistent from year to year. The severity of tobacco budworm feeding damage was recorded for individual plants in each treatment, and damage averaged over pyrethroid treatments was 54.17% lower than the untreated control in 2001 and 79.84% lower in 2003. Pyrethroid treatments had no impact on yield of cured leaf in 2001 or 2003 compared with controls. The use of pyrethroid insecticides in flue-cured tobacco will increase the selection pressure placed on tobacco budworm populations in North Carolina. As a result, resistance to this class of insecticides may develop at an accelerated rate.