Determination of lethal concentration (LC50) for different insecticides against third instar larvae of Helicoverpa armigera (Hubner) (LEPIDOPTERA:NOCTUIDAE)

oleh: M. Hamed, Rashid A. Khan, Farhat Fatima Jamil

Format: Article
Diterbitkan: Prince of Songkla University 2006-03-01

Deskripsi

The efficacy of LorsbanTM, Alpha-cypermethrinTM and KarateTM was assessed by larval dip bioassay against third instar larvae of American bollworm, Helicoverpa armigera (Hub.) collected from a cotton field at Faisalabad and reared in the laboratory until F1 generation. Third instar larvae were used to assess the toxicity of insecticides after 48 hrs of insecticide treatments. Results showed that toxicity of Karate was above all with LC50 of 71.31ppm followed by Alpha-cypermethrin with LC50 287.87 and Lorsban 464.85, respectively. These results showed the increased resistance of H. armigera against Lorsban in F1 generation under laboratory conditions.