Genetic analysis of flavonols and phenolic acids in the loquat F1 population of ‘Tangkebaisha’ × ‘Algerie’

Abstract Flavonols and phenolic acids are key determinants of loquat nutritional quality, yet their inheritance remains unclear. In this study, high-performance liquid chromatography–photodiode array detector (HPLC–PDA) profiling of mature fruits from 95 F1 individuals derived from ‘Tangkebaisha’ × ‘Algerie’ identified seven flavonol glycosides and two phenolic acids. Among these, quercetin 3-O-galactoside (Q3Gal) and kaempferol 3-O-rhamnoside (K3Rha) were the most abundant flavonols, whereas neochlorogenic acid (5-CQA) dominated the phenolic acid fraction in both peel and flesh. All the traits exhibited wide transgressive segregation (coefficient of variation (CV), 39.86%–81.48%). Notably, K3Rha, kaempferol 3-O-glucoside (K3Glc), quercetin 3-O-rutinoside, and chlorogenic acid in fruit pulp showed high transmission ability (>110%) and significantly better-parent heterosis (8.86%–88.56%), indicating strong potential for phenolic enrichment. Within the F1 population, line J-TAL-029 accumulated 746.79 μg/g fresh weight (FW) of total flavonols, and J-TAL-087 reached 3100.76 μg/g FW of total phenolic acids, both substantially exceeding parental levels. Significant positive correlations were observed among flavonol glycosides sharing the same aglycone (e.g. K3Rha vs. K3Glc), indicating the feasibility of indirect selection for superior individuals. These findings elucidate the genetic basis of key phenolic compounds in loquat and provide a foundation for biofortification through breeding.