Abstract:

To systematically evaluate the fruit quality of different plum cultivars and identify core quality indicators and characteristic aroma markers，eight plum cultivars cultivated in Xinjiang，China，were selected as experimental materials. These included locally dominant European plums（Prunus domestica L.）（Fengwei Huanghou，Weidi and Hongbulin）and introduced or hybridized Chinese plums（P. salicina Lindl. and hybrids）（Fengtangli，Qingcuili，Younaili，Yinhongli and Pingguoli）. Comprehensive measurements were conducted on appearance quality，texture attributes，sugar and acid components，phenolic compounds，antioxidant activity，and volatile aroma profiles. Fourier transform infrared spectroscopy（FTIR）was employed to analyze characteristic spectral peaks，while headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry（HS-SPME-GC-MS）combined with orthogonal partial least squares discriminant analysis（OPLS-DA）was used to identify characteristic aroma components. Multivariate statistical analysis was further applied for comprehensive evaluation. The results showed significant differences among the eight plum varieties in terms of single fruit weight，firmness，crispness，sugar-to-acid ratio，total phenolic content，and antioxidant activity. Notably，‘Fengtangli’and‘Weidi’exhibited higher sugar-to-acid ratios（13.65 and 12.69，respectively）with rich flavor，while‘Yinhongli’‘Fengwei Huanghou’，and‘Hongbulin’showed higher total phenolic contents. Principal component analysis（PCA）of the electronic nose response values，which clearly discriminated‘Qingcuili’from ‘Fengwei Huanghou’. Cluster analysis divided the eight varieties into two types：a high-polyphenol dark-colored type and a high sugar/acid ratio and ester-rich aroma type. Based on the variable importance in projection（VIP）threshold of > 1，twelve key indicators were identified，among which fruit shape index（1.24）and total flavonoids（1.19）contributed the most. These findings provide a scientific basis for the evaluation of plum germplasm resources and cultivar breeding.

Key words: plum, cultivar, quality traits, antioxidant activity, aroma