Synthetic Pyrethroid Resistance in Field Strains of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) in Tamil Nadu, South India
P. Duraimurugan and A. Regupathy
DOI : 10.3844/ajassp.2005.1146.1149
American Journal of Applied Sciences
Volume 2, Issue 7
Resistance to synthetic pyrethroids was diagnosed in the field population of American bollworm, Helicoverpa armigera (Hubner) from Coimbatore, Tamil Nadu, South India during 2003-2004 cropping seasons. A Discriminating Dose (DD) bioassay technique was used to monitor fortnightly changes in resistance at Coimbatore where number of crops served as host plants for this pest. The resistance level of various synthetic pyrethroids to DDs varied from 80.0 to 96.4%. The extent of resistance in terms of percent survival was 88.1-96.4, 87.2-94.3, 87.0-94.0, 84.3-94.2 and 80.0-91.8% for cypermethrin, fenvalerate, deltamethrin, lambda-cyhalothrin and beta-cyfluthrin, respectively.
© 2005 P. Duraimurugan and A. Regupathy. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.