Floral organogenesis of Handeliodendron bodinieri (Sapindaceae) and its systematic implications
掌叶木的花器官发生及其系统学意义

Floral organogenesis and development of Handeliodendron bodinieri (Sapindaceae), a species endemic to China, 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.