Diversity of Fruit Quality in Astringent and Non-Astringent Persimmon Fruit Germplasm

Persimmon (Diospyros kaki Thunb.) is an economically important tree with a long history of cultivation in China. So far, a total of approximately 1000 varieties have been found in China. To systematically evaluate the diversity of persimmon fruit quality, 22 quality measures of appearance, intrinsic, and sensory quality were evaluated using 61 typical persimmon fruit. According to the findings, the coefficient of variation (CV) of 15 appearance and intrinsic quality index values ranged from 13.81% (fruit shape index) to 165.80% (firmness), and the CV values of 7 intrinsic quality attributes were all higher than 50%, with the CV of total polyphenols and ironic soluble pectin contents (ISP) being as high as 159.82% and 143.80%, respectively. These findings showed that several persimmon germplasm resources had a highly diverse range of fruit quality, wide variation, and distribution. Insoluble tannin and soluble sugar were shown to have a substantial positive correlation with the sensory flavor indexes (p < 0.05), indicating their significance in influencing the flavor quality of persimmon fruit. Cluster analysis was performed utilizing 15 indexes of appearance, intrinsic quality, and 7 indexes of sensory quality. The samples were divided into two groups: group I consisted of 52 pollination-constant and astringent (PCA) and 1 pollination--variant astringent (PVA) persimmon resources, and group II consisted of 6 pollination-constant non-astringent (PCNA) and 2 pollination-variant non-astringent (PVNA) persimmon resources. The results were consistent with the classification based on the mode of astringency loss, indicating that there was a significant difference in the quality of astringent and non-astringent persimmon fruit. This study provides theoretical references for the development and application of persimmon germplasm resources.