Anatomical and ontogenetic studies on the evolution of reproductive organs in tribes Desmodieae and Phaseoleae (Leguminosae)

本文从解剖学和个体遗传学的角度对豆科Desmodieae（豆科Desmodieae）及其外群、豆科Kennediinae亚群和豆科erythrinae亚群的花和果实进行了研究，并推测了这些性状的进化趋势。花的结构将铁杉科的花与铁杉亚族的铁杉属和铁杉属进行了比较。这两个属在雄蕊的内侧基部有花蜜腺。与“简单型”和“爆炸型”两种花型相比较，外群的特征与“简单型”特征相一致。因此，这一结果表明，“简单型”是更原始的，或多形的，在部落的菊形。此外，花形态的有用性检验了部落的石络科。在这个部落，花萼和花瓣被证明是更有用的。通过这项研究，发现了胡枝子属的一个新种，L.hisauchii T.Nemoto & H.Ohashi （Nemoto & Ohashi, 1999）。果实结构：将Desmodieae族果皮的解剖结构与Kennediinae亚族和Erythrininae亚族进行了比较。后两个亚族的厚壁组织纤维呈斜向排列，明显不同于松枝科的横向排列。这表明，在Desmodieae部落中，纤维的共同排列是在该部落分支的根部从Phaseoleae部落的联合亚部落的斜排列进化而来的。利用叶绿体rbcL基因序列数据绘制的分子系统发育树的解剖特征图谱显示，不同枝系的果皮和关节结构的进化趋势存在差异。此外，结果表明，该部落的果实结构的进化与花的结构密切相关。

Flowers and fruits were anatomically and ontogenetically investigated in the tribe Desmodieae of Leguminosae including its outgroups, subtribes Kennediinae and Erythrininae in the tribe Phaseoleae, and then the evolutionary trends of these characters were assumed.1. Flower structureFlowers of Desmodieae were compared with genera Kennedia and Hardenbergia of the subtribe Kennediinae. These two genera have floral nectaries at the inside base of the androecium. In comparison with the two flower types recognized in the tribe Desmodieae, "simple type" and "explosive type", the features observed in the outgroups correspond to those of the "simple type". This result, therefore, suggests that the "simple type" is more primitive, or plesiomorphic, in the tribe Desmodieae.Moreover, the usefulness of flower morphology was examined in the tribe Desmodieae. The calyx and petal were shown to be more useful in this tribe. By this examination one new species of the genus Lespedeza, L.hisauchii T.Nemoto ＆ H.Ohashi, was recognized and published (Nemoto ＆ Ohashi, 1999).2. Fruit structureThe anatomical structures of pericarps of the tribe Desmodieae were compared with those of subtribes Kennediinae and Erythrininae. The latter two subtribes represent oblique arrangement of fibers in the sclerenchyma, which is obviously different from the transverse arrangement commonly found in the tribe Desmodieae. This suggests that the common arrangement of fibers in the tribe Desmodieae is evolved at the root of the clade of the tribe from the oblique arrangement in the allied subtribes of the tribe Phaseoleae.Mapping of anatomical characteristics onto the molecular phylogenetic tree obtained from sequence data of chloroplast rbcL gene shows differences in evolutionary trends of pericarp and joint structures in each clade of the tree. Moreover, the evolution of fruit structure is shown to be closely correlated with that of flower structure in the tribe Desmodieae.