Integrated physiological, transcriptomics, and metabolite analysis reveal photosynthetic toxicity related to the bisphenol A stress response mechanism in pepper (Capsicum annuum L.).

Bisphenol A (BPA), an emerging endocrine-disrupting chemical found in irrigation water, soil, and agricultural plastic mulch, presents potential exposure risks to pepper plants (Capsicum annuum L.). This study investigated BPA impact, observing that BPA accumulates in a concentration-dependent manner, with highest levels in roots and lowest in fruit. High BPA exposure decreased photosynthetic pigment content, reduced stomatal size, caused chloroplast dilation, and increased reactive oxygen species and malondialdehyde accumulation, disrupting hormone balance in leaves with a 2.3-fold increase in abscisic acid content under 100 mg/kg BPA treatment. Integrated multi-omics analyses revealed that BPA toxicity operates through interference with galactose metabolism, starch-sucrose metabolism, plant hormone signaling, and glutathione metabolism pathways. Key molecular responses included significant downregulation of photosynthesis-related genes and substantial metabolic perturbations, notably an 8.1-fold reduction in uridine diphosphate glucose and 10.6-fold accumulation of indole-3-ethanol. By employing an integrated multi-omics approach, this study provides a comprehensive mechanistic understanding of BPA phytotoxicity that extends beyond conventional physiological observations. The findings offer novel insights into the molecular regulatory networks underlying plant stress responses to endocrine-disrupting chemicals.