This study was carried out determination of characteristics of leaf and fruit of 13 astringent persimmon (Diospyros kaki) cultivars cultivated in Gyeongsangnam-do, Korea. In leaf size, Deabonggam was smaller than that of other astringent persimmon cultivars, however, Dansungsi and Bansi were largest compared to other persimmon cultivars. Fruit width size of Sancheong Deabonggam and Bansi were the biggest. And fruit width size was the biggest in Sancheong Deabonggam. When same cultivars as Dansungsi and Godongsi were cultivated at other regions, it was not somewhat different in fruit weight. The size of fruits of the cultivar varied depending on the maturation of the fruits. In immature fruit, Curigam and Susi cultivars were the biggest and these cultivars were also were the biggest in mature-green fruit. In full ripe fruit, Hamyang Daebonggam and Hadong Daebonggam and Daeheakmu were bigger than that of other cultivars. When the astringent persimmon varieties collected in July were divided into three clusters, group A had a higher leaf area and the lightest fruit weight than the other clusters. In cluster C, the leaf area was small, but the fruit weight was classified as heavier than the other clusters. This study is expected to be widely used for breeding, conservation and processing of sweet persimmons.

In our studies on the role of -galactosidase in fruit softening, significant difficulty, was encountered in our attempts to extract RNA from persimmon(Diospyros kaki L. cv. Fuyu) fruit due to astringency and tannin content. Initial, unsuccessful RNA extractions involved methods using guanidinium isothiocyanate/CsCl with and without polyvinylpyrrolidone(PVP), phenol/sodium lauryl sulfate(SDS), guanidinium hydrochloride, as well as polysomal RNA purification method that used 0.2 M Tris-HCI (pH 9.0) containing KCI, Mg-acetate, EDTA, -mercaptoethanol, and sucrose. A method was devised which employed treatment of fruit with CO2 gas to diminish astringency prior to RNA extraction, followed by extraction of tissue powders with Proteinase K extraction buffer containing PVP and ascorbate at an alkaline pH. This procedure resulted in the removal of tannins and other polyphenolics and extraction of relatively large amount of high-quality RNA suitable for cDNA library construction and polymerase chain reaction(PCR). Futhermore, the procedure does not use the toxic and corrosive chemical guanidinium isothiocyanate or require ultracentrifugation.