对光皮树小孢子发育特点及其与花器外部形态的相关性进行研究，同时观测不同无性系花粉粒的超微结构。结果表明：光皮树小孢子属正常双子叶植物小孢子发育，发育过程分为花粉母细胞时期、四分体时期、单核细胞和双核细胞时期；小孢子发育与花器外形发育存在一定的相关性，花序/花蕾大小随着小孢子的发育而增大，花蕾的颜色随着小孢子的发育由花粉母细胞时期的深绿色变为后双核细胞时期的白色。光皮树花粉粒为长球形，赤道面观为四角形，极面观为三裂近圆形、略呈三角形，萌发孔为沟状，有3条孔沟，花粉粒外壁表面有雕纹，为疏密不一致的小穴，不同无性系之间花粉粒的超微结构差异不显著。%The relativity of the microsporogenesis and the corresponding exterior morphological development of floral organ were studied, meanwhile the scanned morphological structure of pollen grain from different clones was observed by scanning electron microscope. The results show that the microsporogenesis of Cornus xvilsoniana was normal dicotyledon microsporogenesis, there were four development periods: microsporocyte, tetrad, monocyte period and binu-cleate cells period; the microsporogenesis development period was related to the changes of floral organ morphology. During the process of microsporogenesis, the size of inflorescences and the buds increased following the microsporogenesis, and the colour of buds changed from black green in microsporocyte period to white in the binucleate cells period. Commonly pollen grain of Cornus wilsoniana was prolate, which is quadrilateral by the equatorial plane view, and suborbicular of three stomium or slight trilateral by the polar view, similar furrow, there were three germinal pore furrows, sculpture of grain exine were little caves distributing unevenly, However ultra microstructure of pollen grain from diffent clones of Cornus wilsoniana was a little difference.
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