Synergistic effects of chlorantraniliprole and camptothecin on physiological impairments, histopathological, biochemical changes, and genes responses in the larvae midgut of Spodoptera frugiperda

Pestic Biochem Physiol. 2023 Apr:191:105363. doi: 10.1016/j.pestbp.2023.105363. Epub 2023 Feb 4.

Abstract

Spodoptera frugiperda is an economically important agricultural pest and poses a serious threat to food security globally. Its management is gravely challenged by its high polyphagous nature, strong migratory ability, and massive fecundity. Chlorantraniliprole (CHL) is widely utilized in controlling S. frugiperda, its intensive application and over-reliance pose adverse health risks, development of resistance, toxicity to beneficial insects, natural enemies, and environmental contamination. To address S. frugiperda resistance to CHL and its inherent challenges, this study explores the synergistic effects of camptothecin (CPT) with CHL in its management. The binary mixed adversely induced the larvae weight and mortality when compared to single-treated. CHL + CPT (1:20 mg/L) had the highest larvae mortality of (73.80 %) with a high antagonistic factor (0.90), while (1:10 mg/L) with (66.10%) mortality exhibited a high synergistic factor (1.43). Further, CHL + CPT (1:10 mg/L) considerably altered the midgut epithelial cell, peritrophic membrane, microvilli, basement membrane, and regenerative cells. For biochemical analysis, CHL + CPT (1:10 mg/L) significantly decreased glutathione-S-transferase (1-chloro-2,4-dinitrobenzene CDNB) and cytochrome P450 (7-ethoxycoumarin O-deethylation) activities in the midgut in a dose and time dependent manner. Based on RNA-Seq analysis, a total of 4,373 differentially expressed genes (DEGs) were identified from the three treatments. CPT vs CK (Control) had 1694 (968 up-, 726 down-regulated), CHL vs CK with 1771 (978 up-, 793 down-regulated), and CHL + CPT vs CK had 908 (394 up-, 514 down-regulated) DEGs. The enrichment analysis disclosed significant pathways such as metabolism of xenobiotics by cytochrome P450, glutathione metabolism, TOLL and IMD (Immune Deficiency) signaling pathway, longevity regulating pathway. This study provides basis to expatiate on the molecular toxicological mechanism of CHL + CPT in management of fall armyworm.

Keywords: Binary mixed; Cytochrome P450; Glutathione-S-transferase metabolism; RNA-Seq analysis.

MeSH terms

  • Animals
  • Body Weight / drug effects
  • Camptothecin* / administration & dosage
  • Camptothecin* / pharmacology
  • Camptothecin* / toxicity
  • Cytochrome P-450 Enzyme Inhibitors / administration & dosage
  • Cytochrome P-450 Enzyme Inhibitors / pharmacology
  • Cytochrome P-450 Enzyme Inhibitors / toxicity
  • Cytochrome P-450 Enzyme System / metabolism
  • Drug Synergism
  • Food Security
  • Gene Expression Profiling
  • Gene Ontology
  • Glutathione Transferase / metabolism
  • Insecticides* / administration & dosage
  • Insecticides* / pharmacology
  • Insecticides* / toxicity
  • Larva* / anatomy & histology
  • Larva* / drug effects
  • RNA-Seq
  • Reproducibility of Results
  • Secondary Metabolism
  • Spodoptera* / anatomy & histology
  • Spodoptera* / drug effects
  • Spodoptera* / growth & development
  • Spodoptera* / physiology

Substances

  • chlorantranilipole
  • Camptothecin
  • Insecticides
  • Glutathione Transferase
  • Cytochrome P-450 Enzyme System
  • Cytochrome P-450 Enzyme Inhibitors