掌叶木的花器官发生及其系统学意义

Floral organogenesis of Handeliodendron bodinieri (Sapindaceae) and its systematic implications

利用扫描电子显微镜和光学显微镜观察了掌叶木的花器官发生过程。观察结果表明:花序原基最先发生,然后形成两个大小不一的花原基;萼片原基的发生不同步,螺旋状向心发生;4–5枚花瓣原基以接近轮状方式近同时发生;不存在花瓣-雄蕊复合原基;7–8枚雄蕊原基为近同时发生,其生长较花瓣原基快;心皮原基最后发生,3枚心皮原基为同时发生。花为单性花。在雌花中,子房膨大而雄蕊退化。在雄花中,雄蕊正常发育,子房退化。讨论了掌叶木花器官发生和发育的系统学意义。

Floral organogenesis and （Sapindaceae）, a species endemic to China, development of Handeliodendron bodinieri were studied under scanning electron microscope and optical microscope. The results are as follows： the inflorescence primordium initiates at first, forming 2 unequal flower primordia. The sepal primordia initiate in spiral order and are not synchronous. Four to five petal primordia initiate in whorls simultaneously. The petal and stamen primordia initiate separately, and there is no petal-stamen complex. Seven to eight stamen primordia initiate nearly at the same time and grow more quickly than the petal primordia. At last, 3 carpel primordia appear simultaneously and close up gradually to form the ovary. The flowers of H. bodinieri are unisexual. In the female flower, the ovary bulges and the stamens degenerate, whereas the male flower, the stamens grow normally but the ovary degenerates. The systematic implications of floral organogenesis and development of H. bodinieri are discussed.