Comparative toxicity of certain pesticides to peach fruit fly, Bactrocera zonata Saunders (Diptera: Tephritidae) under laboratory conditions

Peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), has been a serious pest in the last decade attacking a wide range of fruits in Egypt. The toxicity of Malathion, Diazinon, Methoxyfenozide, and Lufenuron to adult males and females of Bactrocera zonata was studied under laboratory conditions. Diazinon was the most toxic among the tested compounds followed by Malathion, Lufenuron and Methoxyfenozide to Bactrocera zonata at 24 h post treatment, the respective LC50 values were 0.20 ppm, 0.48ppm, 8.97ppm, and 9.73ppm for males and 0.26 ppm, 0.91ppm, 11.26ppm, and 14.12ppm for females. At 48 h post treatment Diazinon was the most toxic followed by Malathion, Methoxyfenozide and Lufenuron to Bactrocera zonata, LC50 values were 0.09ppm, 0.34ppm, 1.60ppm, and 1.88 ppm for males and 0.14 ppm, 0.44ppm, 1.68ppm and 2.17 ppm for females. At 72 h post treatment Diazinon was the most toxic followed by Malathion, Lufenuron and Methoxyfenozide to Bactrocera zonata, LC50 values were 0.02 ppm, 0.13ppm, 0.22ppm and 0.51ppm for males and 0.07 ppm, 0.16ppm, 0.55 ppm and 0.62 ppm for females. It is observed that LC50 values for treated adult females increased more than in the treated adult males at 24 h, 48 h, and 72 h post treatment. It means that the adult males were more susceptible to the tested insecticides than the adult females.