| Summary: | 碩士 === 臺灣大學 === 生態學與演化生物學研究所 === 98 === The genus Bulbophyllum is the largest taxon in Orchidaceae and there are nearly 2000 species distributed in the pantropical region. There were 21 species documented in the Flora of Taiwan second edition, and several new Bulbophyllum taxa were described afterwards and currently there are 23 species and 7 varieties recorded in Taiwan. This study analyzed 28 Bulbophyllum taxa from Taiwan and 10 others from Southeast Asia. Three chloroplast DNA molecular markers were examined in this study: matK partial sequence, trnC-rpoB intergenic spacer and trnL-trnF intergenic spacer partial sequence. Phylogenetic analysis was perfomed using maximum parsimony, neighbor-joining and Bayesian inference. Morphological character evolution was examined on the molecular phylogenies.
Three different chloroplast DNA markers show similar pattern: solitary inflorescence group were at the basal position (especially the group without pseudobulb). Section Cirrhopetalum (lateral sepals longer than dorsal sepal, usually umbellate inflorescence) formed a core group, separated from those with shorter lateral sepals.
Intraspecific studies of molecular phylogenetics from B. albociliatum、B. hirundinis and B. elecrtinum were perfomed. The result show that a Nantou sample of B. albociliatum var. albociliatum with a larger variation in nucleotide sequence.
The result of three chloroplast markers used in this study show matK region is not a suitable marker in Bulbophyllum in Taiwan, because of its low sequence variation and problematic phylogenetic relationship of B. affine and B. macraei. New molecular markers are needed for phylogenetic studies of Bulbophyllum in the future.
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