Pollen Morphology of Osmanthus (Oleaceae) in China and Its Systematic Significance
中国木犀属花粉形态研究及其系统学意义

Morphological studies of the pollens of 21 species in four sections of genus Osmanthus from China are reported in this paper. The pollen grains are spheroidal or subprolate in shape. The sculptures of the pollen exine are unexceptionally reticulate. Most species are 3-colporate, and few are 4-colporate or with 6 apertures. The ora are obvious or not obvious. Especially, pollens of each of the nine species are 3-colpate and 3-colporate; O.hainanensis is 3 and 4-colporoidate. Transitional types of the apertures also exist in these species. Some characters indicate that the pollen aperture of genus Osmanthus is on the transitional stage from simple to compoundapertures in Oleaceae. Two types of pollens can be divided based on whether or not the lumen become small from the center of the mesocolpium toward the colpi. The sculpture characters show correspondence to the sectionaldivision of Osmanthus, and to some extents the comprehensive characters of pollen morphology have correlation with that of the structural morphology. In general, pollen morphology presents a systematic significance in the genus Osmanthus.