Deciphering quality decline in Peucedani Radix: An interpretable deep learning framework integrating multimodal analysis across the supply chain

• Comprehensive quality assessment of Peucedani Radix across the entire supply chain. • Integrated chemical, molecular, and spectroscopic analyses reveal multifactorial quality decline. • Interpretable deep learning model achieves over 90% accuracy for rapid authentication. • Proposes a novel "gold-standard verification and on-site rapid screening" quality control paradigm.