Sublethal concentrations of lambda-cyhalothrin reduce fecundity by affecting the hormone-vitellogenin signaling pathway in Chrysoperla sinica.

Nian-Meng Wang; Zi-Jian Wang; Si-Yuan Gong; Ya-Shu Zhang; Chao-Bin Xue

The lacewing, Chrysoperla sinica Tjeder, as an important insect predator, plays an important role in biological control. In this study, exposure of the lacewing larvae to sublethal concentrations (LC1 and LC10) of lambda-cyhalothrin (λCy) inhibited the expression of the CsVg gene, decreased vitellogenin and vitellin content, affected ovogenesis and ovarian development, as well as significantly reduced oviposition and egg hatching in female adults. Further investigations indicated that the sublethal concentrations of λCy decreased juvenile hormone (JH) and 20-hydroxyecdysone (20E) titers in female adults during oviposition peak period, led to significant decrease in the activities and gene expression of key enzymes involved in their synthetic pathways. They also inhibited the expressions of the JH receptor gene, methoprenetolerant (Met), downstream transcription factors, krüppel homolog 1 (Kr-h1) in JH signaling and Broad-Complex (Br-C) in 20E signaling, specifically during oviposition peak period in female adults. Offsprings consecutively exposed to sublethal concentration of λCy exhibited hereditary and accumulative effects of hormone-related gene expression in this lacewing. In conclusion, this study demonstrates that sublethal concentrations (LC1 and LC10) of λCy causes hormonal signaling malfunction in C. sinica, resulting in the down-regulation of CsVg, which affect ovarian development and ovogenesis, and ultimately lead to severe decrease in fecundity.

JUVENILE hormones; GENE expression; LACEWINGS; OVIPARITY; SYNTHETIC enzymes

Entomologia Generalis, 2024, Vol 44, Issue 6, p1459

0171-8177

Academic Journal

10.1127/entomologia/2024/2687