G Komala, Mookiah Shanthi, Marimuthu Murugan, G K Sujayanand, Sampathrajan Vellaikumar, Gnanadhas Preetha, Govindasamy Kavitha, Kolanchi Prakash
Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, 641003, Tamil Nadu, India.
Centre for Plant Protection Studies, Tamil Nadu Agricultural University, Coimbatore, 641003, Tamil Nadu, India.
Sci Rep. 2025 Aug 20;15(1):30643. doi: 10.1038/s41598-025-01605-y.
The Fall armyworm (Spodoptera frugiperda) presents a major challenge to global maize production. This study evaluates the insecticidal potential of Simarouba glauca extracts as an eco-friendly alternative to synthetic pesticides. Bioactive compounds were extracted from different plant parts using various solvents, with seeds yielding the highest recovery in n-hexane, while the bark extracted with ethyl acetate exhibited the lowest median lethal concentration (LC₅₀) of 4.80%. Antifeedant assays demonstrated that cold-pressed seed oil achieved over 52.3% feeding inhibition at elevated concentrations. Gas chromatography-tandem mass spectrometry identified key metabolites, including gamma-sitosterol and lanosta-8,24-dien-3-one, with distinct metabolic signatures in bark extracts, as revealed by principal component analysis and clustering techniques. Transcriptomic analysis using RNA sequencing and differential gene expression profiling identified 734 genes with significant expression changes, implicating disruptions in metabolic and signaling pathways associated with insect mortality and feeding deterrence. Molecular docking studies targeting cytochrome P450 and odorant-binding proteins confirmed strong ligand interactions, suggesting interference with detoxification and chemosensory functions. Our findings suggest S. glauca as a viable natural alternative to synthetic pesticides, paving the way for future research into its bioactive compounds for pest management strategies that support ecological and agricultural sustainability.
草地贪夜蛾（Spodoptera frugiperda）对全球玉米生产构成重大挑战。本研究评估了 glauca 苦配巴提取物作为合成农药的环保替代品的杀虫潜力。使用各种溶剂从不同植物部位提取生物活性化合物，种子在正己烷中的回收率最高，而用乙酸乙酯提取的树皮的半数致死浓度（LC₅₀）最低，为4.80%。拒食试验表明，冷榨种子油在高浓度下实现了超过52.3%的取食抑制。气相色谱 - 串联质谱法鉴定出关键代谢物，包括γ-谷甾醇和羊毛甾 -8,24-二烯 -3-酮，主成分分析和聚类技术显示树皮提取物中具有独特的代谢特征。使用RNA测序和差异基因表达谱分析的转录组学分析鉴定出734个具有显著表达变化的基因，这表明与昆虫死亡率和取食威慑相关的代谢和信号通路受到破坏。针对细胞色素P450和气味结合蛋白的分子对接研究证实了强烈的配体相互作用，表明对解毒和化学感应功能有干扰。我们的研究结果表明，glauca苦配巴是合成农药的可行天然替代品，为未来研究其生物活性化合物用于支持生态和农业可持续性的害虫管理策略铺平了道路。
