Pyrethroid Resistance in Heliothis armiger (Hübner) (Lepidoptera: Noctuidae) in Australia

Publisher Website
Google Scholar
Abstract
Data are presented for permethrin, fenvalerate, cypermethrin, and deltamethrin tested against laboratory-reared third-instar Heliothis armiger (Hübner) collected m Australia from 1977 to 1983. There was no evidence of resistance until January 1983 when a strain was submitted from cotton at Emerald, central Queensland, where pyrethroids had failed to give adequate control of H. armiger. Initial tests indicated that ca. 50%of the strain was resistant. Survivors of discriminating concentrations of cypermethrin, deltamethrin, and fenvalerate were retained to give a selected strain which was 15-fold, 20- to 30- fold, and 20-fold resistant, respectively, to these chemicals at the LC50. Selection at twice these concentrations gave a strain which was 50-fold resistant to fenvalerate. Resistance to permethrin another unselected field strain was ca. 10-fold. Forty-three strains of H. armiger were tested with a discriminating concentration of fenvalerate in 1983; resistant individuals were. Identified 17 of these. All five strains from Emerald contained a high proportion of resistant individuals. The results indicated a low overall frequency of resistant idividuals in the remaining cotton-growing areas in Queensland and New South Wales.