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

Abstract

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.

Phenotypic Diversity and Relationships of Fruit Traits in Persimmon (Diospyros kaki Thunb.) Germplasm Resources

“…In this study, 56 fruit phenotypic traits from 150 persimmon germplasm resources with consistent establishment and cultivation management conditions were comprehensively analyzed. Previous studies have revealed a wide range of variation (ranging from 11.06% to 50.88%) in persimmon fruit traits, and our results also show coefficients of variation in phenotypes ranging from 5.10% to 56.78% [17,24,25]. The large coefficients of variation indicate a large diversity of phenotypic traits in persimmon germplasms, which can provide rich test materials for genetic improvement and variety selection.…”

“…One of the most critical aspects that determines a fruit's economic value and has a direct impact on its ability to compete in the market is the fruit's quality [39]. Both the intrinsic qualities and the appearance of the fruit are considered to be part of the fruit's quality [17]. Color, shape, and size are the appearance qualities of the fruit that are important indices for evaluating the quality of commodities and the characteristics of varieties, and they serve as a basis for satisfying consumers' demands for a "good look"; fruit hardness and water content are internal qualities, which impact customers' purchasing decisions [17,40].…”

“…Both the intrinsic qualities and the appearance of the fruit are considered to be part of the fruit's quality [17]. Color, shape, and size are the appearance qualities of the fruit that are important indices for evaluating the quality of commodities and the characteristics of varieties, and they serve as a basis for satisfying consumers' demands for a "good look"; fruit hardness and water content are internal qualities, which impact customers' purchasing decisions [17,40]. Thus, a comprehensive analysis of multiple traits is necessary to improve the efficiency and accuracy of selection in breeding and meet consumers' requirements for high-quality persimmon fruits [41].…”

“…The study of phenotypic diversity can elucidate the structure and laws of population variation and thereby provide an important basis for the formation mechanism of complex traits through the deep excavation of genetic resources [15]. Genetic diversity is characterized by analyzing variations at the DNA level, phenotypes, and physiological characteristics [16][17][18][19]. The genetic diversity in persimmon germplasm resources has recently been reported from a study mainly focusing on the phenotypic diversity of the leaves and some fruit traits [20], the variation in the flavonoid and polyphenol contents [21], and the variation in the ascorbic acid content of the leaves [22].…”

“…Two articles on the germplasm evaluation by Guan et al included a large number of samples, but the number of traits measured was small (approximately 20) and these included not only fruit traits but also other tree growth traits, with limited attention given to the fruit traits. Although an article by Fu et al measured 22 fruit traits, the sample size was small, including only 61 [17]. The genetic improvement in key traits is a conventional and effective breeding approach for crops and economic trees [20], and the establishment and development of morphological traits is an important basis for genetic diversity studies.…”