Flupyradifurone Induces Transgenerational Hormesis Effects in the Cowpea Aphid, Aphis Craccivora (Koch)
Abstract Insecticide induced-hormesis, a biphasic phenomenon ,with low-dose stimulation and high-dose inhibition, which effectively contributes to pest resurgence. Although cowpea aphid, Aphis craccivora (Koch) (Homoptera: Aphididae), is the most infection insect to legume crops in Egypt, its’ hormesis to flupyradifurone did not previously establish. Therefore, age-stage two-sex life analysis was used to investigate the sublethal and transgenerational effects of flupyradifurone on two successive generations of A. craccivora. Leaf-dip bioassay method revealed high toxicity of flupyradifurone against A. craccivora with LC50 value of 1.82 mg L-1 after 48 h exposure. Treatment of parent generation (F0) with LC10 and LC25 of flupyradifurone significantly increased the longevity and fecundity of the directly exposed adults. The results of transgenerational effects showed that treatment of (F0) with LC25 induced a significant hormetic effects in progeny generation (F1). Furthermore, flupyradifurone at LC25 significantly enhanced the biological traits such as intrinsic rate of increase (r), finite rate of increase (λ) and net reproductive rate (R0) compared with the control. Similarly, both LC10 and LC25 caused a significant increase in the mean generation time T (d). Conversely ,both treatments had a significant decrease in the doubling time (DT). In conclusion, the obtained data demonstrate that exposure of (F0) to flupyradifurone at LC10 and LC25 enhanced longevity and fecundity in of the directly exposed adults of A. craccivora and induced transgenerational hormesis across the subsequent (F1) generation. These grades must be taken into consideration when using flupyradifurone against cowpea aphids.