Genetic diversity among germplasms of Diospyros kaki based on SSR markers

• There were a large number of SSR variances in germplasms of Diospyros kaki.
• Genetic diversity in Qinling Moutain was highest and Dabieshan Mountain was lowest.
• Some PCA cultivars of synonyms or homonyms were successfully identified.
• Most Chinese PCA types were classified inconsistent with their geographic origins.
• Chinese PCNA varieties were close to Chinese PCA cultivars and distant to Japanese PCNA cultivars.

Persimmon (Diospyros kaki Thunb.) has been widely cultivated in China but the majority of its germplasm accessions are pollination constant and astringent (PCA) type with serious issues of synonyms and homonyms. In order to identify the germplasm resources, genetic diversity and relationship among 133 accessions originating from China, Japan and America were elucidated based on SSR (simple sequence repeat) markers. A total of 158 alleles and 610 genotypes were obtained from 17 loci, with a mean value of 9.29 alleles and 35.88 genotypes per locus, respectively. The analysis of genetic variation revealed high SSR polymorphism both in Chinese and Japanese cultivars. Genetic diversity of varieties in Qinling Mountain was highest and Dabieshan Mountain was lowest. The majority of Chinese PCA genotypes were classified into a mixing group without agreement with their geographic origins in the cluster and principal coordinate analysis. All the genotypes of D. kaki were grouped distantly from the related species which were distinguished completely by 17 SSR markers. A few Chinese PCA cultivars of synonyms or homonyms such as “Niuxinshi”, “Damopan” and “Shuishi” were efficiently identified. The results indicated that Chinese PCNA varieties were closely related with Chinese PCA cultivars and revealed relatively distant relationships with Japanese PCNA types.