南天竹属的花部器官发生及其系统学意义

FLORAL ORGANOGENESIS AND ITS SYSTEMATIC SIGNIFICANCE OF THE GENUS NANDINA (BERBERIDACEAE)

报道了南天竹（ＮａｎｄｉｎａｄｏｍｅｓｔｉｃａＴｈｕｎｂ．）（小檗科）的花部器官发生。发现该属植物萼片、花瓣和雄蕊的发生式样为三数轮生；雄蕊与花瓣是经它们所具有的共同原基进行侧向分裂而形成的；花瓣发育早期存在迟滞发育的阶段；心皮发生属于瓶状发生类型。讨论了花器官的三基数性质，小檗科花瓣的来源，雄蕊对瓣着生及单心皮雌蕊的形成等问题。对本属的花部个体发育性状同小檗科中已有报道的红毛七属（Ｃａｕｌｏｐｈｙｌｕｍ）、足叶草属（Ｐｏｄｏｐｈｙｌｕｍ）进行了比较，萼片多数轮列与心皮发生的多态现象是南天竹属的独特性状。

The initiation of the floral organs of Nandina domestica Thunb.(Berberidaceae) is of the trimerouswhorled pattern. Stamens and petals grew out from the lateral bifurcation of the common stamenpetal primordia; but petals underwent retarded periods of growth in their early development. Carpel initiation belongs to the ascidiate type. Some aspects concerning the trimerous floral organs, the origin of petals, stamen insertion pattern and monocarpellary pistil were discussed. In addition the floral ontogenetic characters among three genera of the Berberidaceae, i.e., Caulophyllum, Podophyllum and Nandina were compared. It is inferred that the trimerouswhorled arrangement and the diversity of carpel initiation were the two unique characters of Nandina.