Germplasm-specific phenolic signatures in pear leaves: Comparative variation profiling via UPLC-MS/MS.

Pear (Pyrus L.) is abundant in phenolic compounds which significantly contribute to functional properties. This study analyzed the phenolic profiles in the leaves of 460 pears using UPLC-MS/MS. A total of 28 phenolic compounds were identified, including one hydroxyphenyl-glucopyranoside, two hydroxycinnamates, five flavanols, four flavonoids, and sixteen flavonols, displaying pronounced species-specific and spatial variation. Arbutin emerged as the predominant phenolic component, accounting for 60.36 % of total phenolics, but was significantly less abundant in P. calleryana compared to others. European pears were richer in rutin, while Asian pears had higher concentrations of luteolin 7-O-glucoside. Chlorogenic acid levels showed a positive correlation with the varietal-origin altitude, while luteolin 7-O-glucoside and chrysoeriol 7-O-glucoside were negatively correlated with latitude. Varieties BT, YBMY, and XH_js003 exhibited high phenolic diversity, whereas JT41H, CPS, and ZYX possessed high arbutin. This study provides a comprehensive profile of pear phenolics, thereby enhancing their utilization in bioactives and understanding of adaptations.