Effects of diazinon on antioxidant enzymes and adult emergence of the parasitoid Pimpla turionellae L. (Hymenoptera: Ichneumonidae)

Abstract

In this study, the effects of the organophosphorus insecticide diazinon on antioxidant enzyme activities, and female and total adult emergence ratios of Pimpla turionellae L., were investigated when using a synthetic diet containing 0.01, 0.10, 0.25, 0.50 and 0.75 ppm of the insecticide. Sublethal concentrations of diazinon were supplied to P. turionellae for 24, 48, 72 and 96 hours for enzyme activity and thirty days for determining emergence ratios.

P. turionellae gave different antioxidant responses to insecticidal stress, depending on the concentrations and diazinon exposure time. When compared to the control and especially in high concentrations (0.50 and 0.75 ppm), diazinon increased SOD activity. Although diazinon also caused increases in CAT activity, these increases were not consistent. This study found that the CAT activity didn't fall below the control level.

Diazinon significantly reduced female and total adult emergence of P. turionellae and SOD played a more significant protective role against diazinon toxicity.