关键词: 美丽胡枝子, 二色胡枝子, 花粉形态

Abstract: Lespedeza formosa is a kind of euryoecious plant with great resistibility. There are some experimental research reports on the palynology of the Lespedeza Michx. from Shandong，but nor the submicrostructure of the pollen of the L. formosa. In this paper pollen morphology of the L. formosa was examined by the scanning electron microscope（SEM），and using the L. bicolor as contrast which is regarded as the genus species of inferior organic evolution in Lespedeza Michx. It showed that the polar axis of the L. formosa pollen is 23.7 μm，the equatorial axis is 14.2 μm，and the pollen grains are even in size；while the polar axis of the L. bicolor pollen is 20.3 μm，the equatorial axis is 11.5 μm，pollen grains are uneven in size. In equatorial view，pollen grain of the L. formosa is of elliptic，while the pollen grain of the L. bicolor is of rectangular. In polar view，the pollen grains of the two species both have three germinal furrows. Those data are in accordance with the pollen morphology characteristics of the Lespedeza Michx. According to the pollen surface ornamentation，the L. bicolor is more advanced genus species than the L. formosa，and the latter is the genus species of inferior organic evolution in Lespedeza Michx. in Shandong.

Key words: Lespedeza formosa, Lespedeza bicolor, pollen morphology