普通枇杷、大渡河枇杷、栎叶枇杷的亲缘关系探讨

A study of the sibship among Eriobotrya japonica Lindl, E. prinoides Rehd. & Wils. var. daduheensis H.Z. Zhang and E. prinoides Rehd.& wils.

通过对普通枇杷、大渡河枇杷、栎叶枇杷核型及过氧化物同工酶分析；探讨了三者的亲缘演化关系。结果表明，三个分类群核型较相似，表明其亲缘关系密切，具种间杂交的细胞学基础。但核型类别有所不同，普通枇杷属３Ａ型，大渡河枇杷既有３Ａ也有２Ａ型，栎叶枇杷为２Ａ型。同工酶结果显示，三个分类群酶谱差异明显，且大渡河枇杷具一定程度的杂合型酶谱。结合植物学形态、孢粉学、地理分布进行分析后，认为三个分类群可能为种间杂种演化关系，即大渡河枇杷可能来源于普通枇杷与栎叶枇杷的杂种，并推测，大渡河枇杷可能是一个种，Ｅ．Ｘｄａｄｕｈｅｅｎｓｉｓ（Ｈ．Ｚ．Ｚｈａｎｇ）Ｂ．Ｔａｎｇｖａｓｓｕｇｇｅｓｔｅｄ．

The present studies deal with the sibship of the three taxa of the genus Eryobotrya by using Karyotype and isozymes analyses. The relatively similar somatic karyotypes of the three taxa, which may be the cytological basis of hybridization among them, make clear that they are closely related taxa. But the asymmety of E. japonica is 3A type, E. prinoides is 2A type, and that of E. daduheensis is either 3A type or 2A type. The results of peroxidase isozymes analysis showed obviously different zymograms among the three taxa, and that of E. daduheensis also displayed some extent of hybridized zymograms between the othe two taxa. With related data of characters of morphodogy, palynology, and geographica distributions, the evolutionary relationship among the three taxa may have hybridiztion among species, and E. daduheensis may be a hybrid originated from hybridization between E. japonica and E. prinoides The new rank i.e. E.x daduheensis(H.Z.Zhang) B. Tang vas suggested.