Herbivory-induced metabolic reprogramming in soybean cultivars contrasting in resistance to Bemisia tabaci MEAM1.

Abstract

This study examined how herbivory-induced metabolic reprogramming in soybean alters foliar metabolic profiles in cultivars contrasting in resistance to the phloem-feeding insect Bemisia tabaci MEAM1, providing insights into plant responses associated with insect herbivory. Foliar metabolite profiles were compared between 2 contrasting genotypes, AS3810 (resistant) and BÔNUS (susceptible), under infested and non-infested conditions across 4 sampling scenarios integrating phenological stage and response time. Metabolic responses were characterized using gas chromatography-mass spectrometry (GC-MS) combined with univariate (3-way ANOVA) and multivariate analyses (principal component analysis, PCA). Significant main and interaction effects were detected for multiple metabolites, indicating that metabolic responses are strongly dependent on genotype and developmental context. Key compounds associated with treatment effects included salicylic acid, 4-aminobutyric acid (GABA), threonic acid, 2-oxoglutaric acid, glyoxylic acid, malic acid, spermidine, maltotriose, and galactonic acid, with several metabolites showing significant 3-way interactions. The resistant genotype AS3810 exhibited broader and more coordinated metabolic adjustments, particularly in pathways associated with redox balance, carbon allocation, and stress signaling, especially under reproductive-stage conditions. In contrast, BÔNUS showed lower metabolic responsiveness and reduced pathway integration. Multivariate analysis revealed metabolic differentiation among treatments, with defense- and stress-related metabolites contributing strongly to sample differentiation. These findings indicate that herbivory-induced metabolic configurations define distinct biochemical landscapes in host tissues and highlight genotype-dependent metabolic responses associated with herbivory. Identified metabolites represent candidate biochemical indicators of plant responses to B. tabaci MEAM1 infestation and may contribute to future studies of plant resistance mechanisms and resistance-based pest management strategies.