Effects of Methyl Jasmonate Fumigation on the Growth and Detoxification Ability of Spodoptera litura to Xanthotoxin

Abstract

Methyl jasmonate (MeJA) is a volatile substance derived from jasmonic acid (JA), and it responds to interbiotic and abiotic stresses by participating in interplant communication. Despite its function in interplant communication, the specific role of MeJA in insect defense responses is poorly understood. In this study, we found that carboxylesterase (CarE) activities, glutathione-S-transferase (GSTs) activities, and cytochrome mono-oxygenases (P450s) content increased more after the feeding of diets containing xanthotoxin, while larvae exposed to MeJA fumigation also showed higher enzyme activity in a dose-dependent manner: lower and medium concentrations of MeJA induced higher detoxification enzyme activities than higher concentrations of MeJA. Moreover, MeJA improved the growth of larvae fed on the control diet without toxins and diets with lower concentrations of xanthotoxin (0.05%); however, MeJA could not protect the larvae against higher concentrations of xanthotoxin (0.1%, 0.2%). In summary, we demonstrated that MeJA is effective at inducing S. litura defense response, but the enhanced detoxifying ability could not overcome the strong toxins.

Effect of jasmonic acid and ethylene mediate faba bean defense responses to the activity and gene expression of the detoxifying enzyme in Frankliniella occidentalis

“…For example, Tianzi et al (2018) reported that the activities of GSTs and CarE were subsequently stimulated after C. anachoreta larvae that fed on MeJA-treated leaves. An increase in P450 activity in Helicoverpa armigera larvae that fed on MeJA-treated cotton leaves (Fan et al 2014);Chen et al (2023) demonstrated that MeJA effectively induced Spodoptera litura defense response, and lower and medium concentrations of MeJA induced higher activities of detoxification enzymes than higher concentrations. However, Yang et al (2022) reported a significant decrease in the immunity and detoxification metabolism of H. armigera after it fed on cotton treated with JA, indicating that exogenous phytohormone treatment could control pests by inhibiting insect detoxification metabolism.…”

“…2014); Chen et al . (2023) demonstrated that MeJA effectively induced Spodoptera litura defense response, and lower and medium concentrations of MeJA induced higher activities of detoxification enzymes than higher concentrations. However, Yang et al .…”