Deciphering the molecular mechanisms of maize defence against the fall armyworm (Spodoptera frugiperda) through integrated transcriptomics and metabolomics

Nagesh, P and Dhanyakumar, O and Jaba, J and Yogendra, K and Desika, J and Shettigar, N and Gothe, R M and Mohan, S M and Bhaskara Naidu, P and Mishra, S P and Nair, S K and Vivek, B S (2026) Deciphering the molecular mechanisms of maize defence against the fall armyworm (Spodoptera frugiperda) through integrated transcriptomics and metabolomics. Plant Stress, 21. pp. 1-20. ISSN 2667-064X

Text - Published Version Available under License Creative Commons Attribution. Download (17MB)

Abstract

The fall armyworm (FAW), Spodoptera frugiperda, is a highly destructive polyphagous pest that threatens maize production worldwide, particularly in tropical and subtropical agroecosystems. Understanding the molecular basis of host plant resistance is critical for developing durable and sustainable pest management strategies. In this study, we used an integrated transcriptomic and metabolomic approach to dissect defense responses in contrasting maize inbred lines, the resistant CML338 and the susceptible CML451, under FAW-infested and uninfested conditions. RNA-seq generated high-quality datasets with mapping efficiencies of 84–87 % and revealed extensive transcriptional reprogramming in the resistant genotype following infestation. Multivariate analyses showed clear genotype- and treatment-dependent separation, with principal components explaining >60 % of the total variance. Differentially expressed genes were significantly enriched in pathways related to phytohormone signaling, MAPK cascades, transcriptional regulation, fatty acid metabolism, and secondary metabolite biosynthesis. Untargeted LCsingle bondHRMS metabolomics revealed pronounced accumulation of putative resistance-related metabolites in CML338, including fatty acids (linoleic acid, and arachidonic acid) and terpenoids (α-terpineol, capsorubin, 5-hydroxyzeaxanthin, meso‑zeaxanthin, and violaxanthin). Integrated transcriptome–metabolome correlation analysis (PCC ≥ 0.85, P ≤ 0.05) demonstrated tight coordination between metabolite accumulation and the expression of key biosynthetic genes, including TPS, DXS, PLD, LOX, and FAD. Furthermore, in-silico molecular docking showed strong binding of α-terpineol to the FAW gut enzyme Aminopeptidase N1 (−6.6 kcal mol⁻¹), suggesting a potential interaction; however, this is a putative prediction based on computational analysis and requires biochemical and bioassay validation for confirmation. Collectively, this study provides a systems-level understanding of maize–FAW interactions and identifies candidate genes, pathways, and metabolites for breeding insect-resistant maize cultivars.

Item Type:	Article
Divisions:	Global Research Program - Accelerated Crop Improvement
CRP:	UNSPECIFIED
Uncontrolled Keywords:	Fall armyworm, Host-plant resistance, Maize, Metabolomics, Transcriptomics
Subjects:	Others > Fall Armyworm Others > Maize Others > Entomology
Depositing User:	Mr Nagaraju T
Date Deposited:	12 Nov 2026 05:21
Last Modified:	12 Nov 2026 05:21
URI:	http://oar.icrisat.org/id/eprint/13720
Official URL:	https://www.sciencedirect.com/science/article/pii/...
Projects:	CIMMYT International Maize Improvement Consortium for Asia (IMIC-Asia)
Funders:	OneCGIAR Accelerated Breeding Initiative (ABI)
Acknowledgement:	The authors acknowledge Rajendra Badbadwal, Venkata Ramana, and Rajendra Prasad for their extensive support and assistance with the laboratory rearing of fall armyworm (FAW). The AI tool ChatGPT (GPT-5 mini) was used only for grammar checking and proofreading. After using this tool, the authors reviewed the content and took full responsibility for the published article. No AI was used to generate scientific content and figures.
Links:	Google Scholar

View Statistics

Actions (login required)

View Item