Abstract: The objectives of this study were to investigate the effects of pollinizer cultivars on the quality and aroma components of ‘Yali’ pear fruits and to explore the effect of xenia on fruit quality attributes in order to provide a reference for screening for ‘Yali’ pear pollinizer cultivars for improved fruit quality. Thirty-year-old ‘Yali’ pear trees were pollinated artificially with pollen from 18 pollinizer cultivars with different characteristics, and those pollinated with pollen from ‘Xuahuali’ pear was used as a control group. Fruit quality attributes including individual fruit mass, dot diameter, dot density, stone cell content, total soluble solid content, soluble sugar content, total organic acid content, and aroma compounds in mature pear fruit were measured. The effects of different pollinizer cultivars were comprehensively evaluated by principal component analysis (PCA). The results showed that different pollinizer cultivars affected the external and internal quality attributes and aroma components of ‘Yali’ pear fruit, resulting in 12.57%–96.10% changes in them. For pollination with pollen from ‘Nansui’, ‘Housui’ and ‘Korla’ pear, the contents of total soluble solids (TSS) and soluble sugars and TSS-to-acid ratio in ‘Yali’ pear fruit were increased significantly by 0.55%–0.76%, 7.53–16.54 mg/g and 1.96–4.54, respectively, compared with the control group, indicating improved nutritional quality. Using ‘Nansui’, ‘Korla pear’, ‘Crispel’, ‘Lvbaoshi’ and ‘Cuiyu’ pear as pollinizers, the relative contents of volatile esters in ‘Yali’ pear fruit were significantly increased by 8.77–18.85 times relative to the control group. Notably, the relative content of hexyl acetate was increased significantly by 3.76–15.86 times. Furthermore, six unique esters including ethyl acetate, hexanoic acid ethyl ester, butanoic acid ethyl ester, (E)-acetate-2-hexen-1-ol ester, acetic acid-2-phenylethyl ester and ethyl 2-trans-4-cis-decadienoate were detected, which could contribute to improving the aroma of ‘Yali’ pear fruit. Compared with the fruit quality attributes of the male parent, an obvious xenia effect was observed in pollinated pear fruit in terms of stone cell content, fruit texture, TSS content, soluble sugar content, and aroma components but not individual fruit mass, dot diameter, dot density or total organic acid content. The comprehensive evaluation results showed that ‘Nansui’ could be the most suitable pollinizer cultivar for ‘Yali’ pear production.

Key words: Pyrus bretschneideri ‘Yali’; fruit quality; aroma components; xenia effect; comprehensive evaluation