Unravelling soybean responses to early and late Tetranychus urticae (Acari: Tetranychidae) infestation

Soybean is a crucial source of food, protein, and oil worldwide that is facing challenges from biotic stresses. Infestation of Tetranychus urticae Koch (Acari: Tetranychidae) stands out as detrimentally affecting plant growth and grain production. Understanding soybean responses to T. urticae infestation is pivotal for unravelling the dynamics of mite-plant interactions. We evaluated the physiological and molecular responses of soybean plants to mite infestation after 5 and 21 days. We employed visual/microscopy observations of leaf damage, H₂O₂ accumulation, and lipid peroxidation. Additionally, the impact of mite infestation on shoot length/dry weight, chlorophyll concentration, and development stages was analysed. Proteomic analysis identified differentially abundant proteins (DAPs) after early (5 days) and late (21 days) infestation. Furthermore, GO, KEGG, and protein-protein interaction analyses were performed to understand effects on metabolic pathways. Throughout the analysed period, symptoms of leaf damage, H₂O₂ accumulation, and lipid peroxidation consistently increased. Mite infestation reduced shoot length/dry weight, chlorophyll concentration, and development stage duration. Proteomics revealed 185 and 266 DAPs after early and late mite infestation, respectively, indicating a complex remodelling of metabolic pathways. Photorespiration, chlorophyll synthesis, amino acid metabolism, and Krebs cycle/energy production were impacted after both early and late infestation. Additionally, specific metabolic pathways were modified only after early or late infestation. This study underscores the detrimental effects of mite infestation on soybean physiology and metabolism. DAPs offer potential in breeding programs for enhanced resistance. Overall, this research highlights the complex nature of soybean response to mite infestation, providing insights for intervention and breeding strategies.