Transgenerational effects and mechanisms of Cry1Fa toxin on the non-target Myzus persicae

Although extensive research has focused on the effects of Cry toxins produced by Bacillus thuringiensis on target insects, fewer studies have explored their impacts and underlying mechanisms on non-target aphids. Herein, we investigated the effects and mechanisms of Cry1Fa toxin on the non-target peach aphid, Myzus persicae. Toxicity assessments confirmed that M. persicae was insensitive to Cry1Fa toxin. Subsequent transcriptome sequencing and identification of Cry1Fa toxin-binding proteins, along with life table analysis of three successive generations, revealed the transgenerational effects of Cry1Fa toxin on M. persicae. Treatment with Cry1Fa toxin did not significantly alter the life table parameters of the parent generation (F0), which was probably attributed to the significant up-regulation of autophagy-animal, ribosome, lysosome, and oxidative phosphorylation pathways. In the first filial generation (F1), the intrinsic rate of increase (r), finite rate of increase (λ), age-specific survival rate (lx), and age-specific life expectancy (ex) were significantly higher compared with the control group, suggesting a hormetic effect and the growth of aphid population in the F1 generation. The significant up-regulation of ribosome and oxidative phosphorylation pathways might account for these changes. However, the life table parameters of the second filial generation (F2) were not significantly affected, indicating a trade-off in resource allocation across generations. Our results provide valuable insights for the use and assessment of Cry toxins in pest control strategies.