Studies on Removability of Astringency and Gultivar Differentiation in Japanese Persimmon.

根据果实在树上失涩的方式或程度，日本的柿品种被分为4种不同的类型。本研究从种子产生乙醇的能力、花粉和成熟叶片的同工酶谱两个方面探讨了苦涩可去除性与品种分化的关系。种子乙醇产量一般呈双峰曲线，第一个峰值与胚胎的快速生长相吻合。但不同种子部位的乙醇产量没有差异。种子中的乙醇脱氢酶(ADH)活性也随着乙醇产生的开始而增加。授粉恒定型的层积种子的ADH活性往往高于授粉变异型。用授粉恒定型和不收敛型(PCN型)杂交F&lt；12&gt；子代的果实测定了乙醇的产量。有履历的后代。以扶余为亲本的种子乙醇产量差异较大，而以扶余为亲本的种子乙醇产量持续较低，表明种子中存在控制乙醇产量的基因(S)。利用19个品种9个花粉同工酶的68条谱带计算相似指数。不同品种间有较高的相似性。结合葡萄糖磷酸异构酶和苹果酸脱氢酶两种同工酶体系，从163个品种中鉴定出18个品种。然而，4种水果类型之间没有明显的相关性。

Japanese persimmon cultivars are classified into 4 different types depending on the ways or degrees their fruits lose astringency on the tree. This study was undertaken to search for the relationships between removability of astringency and cultivar differentiation in terms of ethanol production by seeds and isozyme patterns of pollen and mature leaves.1). Ethanol production by seeds generally showed 2 peaked curves and the first peak coincided with the rapid growth of embryos. But no difference in ethanol production was observed between seed parts. Alcohol dehydrogenase (ADH) activity in the seed also increased toward the onset of ethanol production. Stratified seeds of pollination constant types tended to show higher ADH activity than pollination-variant ones.2). Ehanol production was determined with fruits of F_<12> progenies obtained from crosses between pollination-constant and nonastringent (PCNA) types. Progenies having cv. Fuyu as a parent showed wide variation in ethanol production while those otherwise constantly produced low ethanol, suggesting the existence of gene(s) governing ethanol production in the seed.3). Similarity indices were calculated using 68 bands obtained from 9 pollen isozymes of 19 cultivars. Higher similarities were found among PCNA cultivars. 18 out of 163 cultivars were identified by combining 2 isozyme systems, glucosephosphate isomerase and malate dehydrogenase, of mature leaves. No relationship, however, was dound among the 4 fruit types.