| Summary: | 博士 === 國立中興大學 === 生命科學系 === 93 === The morphological and molecular phylogenetic relationship of Rhamnaceae in Taiwan was studied using the characters of pollen, venation, wood, and DNA sequences.
According to pollen morphology and sculpture, the Rhamnaceae was classified into three types : Sageretia-type, Phylica-type and Rhamnus-type.
The wood is characterized by diffuse-porous. Pores generally in solitary, in radial multiples or in clusters. Vessel arrangement in diagonal pattern or in dendrtic pattern, simple perforation plated and alternate bordered intervessel pits. Fibers have pits and have no spiral thickenings on the walls. Wood rays are heterogeneous and non-storied,and generally without sheath cells. Ray-vessel pits, same as intervessel pits, are alternate. The wood anatomy characters are similar within genera.
The length of ITS of nrDNA in the taxa surveyed ranged from 692 to 723 bp and trn L and IGS of cpDNA ranged from 1045 to 1180 bp. In total about 1587 sequence data in the taxa are obtained. The G + C content varied from 58.6% to 63.6% in nrDNA,from 33.3% to 36.3% in trn L and 35.1% to 38.2% in IGS. Both the sequence data from ITS with and without 5.8S give concordant phylogenetic trees. For both inter- and intra-generic phylogenetic relationship, the resolution ability of cpDNA is smaller than those of nrDNA. The tree based on by DNA sequence appears to be corresponded strongly with the kinds of fruit types and the positions of ovaries.
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