The Origin and Cultivar Development of Japanese Persimmon ( Diospyros kaki Thunb.)

Persimmon (Diospyros kaki Thunb.) is a hexaploid (2n=6x=90) that originated in southern China through polyploidization from a diploid ancestor. The exact ancestor of persimmon has not been clarified yet though much research has been conducted to elucidate it. Recent studies showed that D. glandulosa and D. oleifera have a close relationship with the diploid ancestor. Many persimmon cultivars have been developed through the long history of cultivation. Based on the nature of loss of astringency of the fruit, persimmon cultivars are classified into four types. There are two non-astringent types, PVNA and PCNA, and the mechanism of astringency loss is different between them. Furthermore, Chinese PCNA cultivar (C-PCNA) was proven to have a different physiological nature from Japanese PCNA cultivars. Though the gene conferring the PCNA or C-PCNA trait has not been identified yet, the nature of astringency loss has been gradually elucidated at the molecular level. (Accepted Apr. 20, 2016)