台灣的映山紅組杜鵑花（Rhododendron sect. Tsutsusi），約十個物種，外表形態上皆極為相近。這些形態相近的類群中，除了唐杜鵑（R. simsii）之外，都屬於台灣特有種，許多例子指出，物種在新形成的年輕島嶼中常有快速演化，進而種化的現象。台灣的映山紅組杜鵑花特有種的比例如此高，加上台灣屬於年輕型島嶼，推測這些形態極為相近的杜鵑可能是近期快速演化的結果。本研究利用母系遺傳之葉綠體基因matK和trnK的內顯子（intron）片段以及核基因RPB2-i intron 2和ITS片段，探討台灣產杜鵑花屬映山紅組植物的親緣關係及演化歷史。
葉綠體基因matK和trnK intorn片段建構的親緣關係圖結果，將台灣映山紅組杜鵑花歸為主要的三群；RPB2-i intron 2片段建構的基因樹將十種杜鵑花歸為主要的兩大群，此片段中除了R. oldhamii以外，其他種類RPB2-i基因片段都帶有兩個copies的現象，且
R. rubropilosum的不同copy分別歸到不同的兩個大群中；而ITS片段所建構的親緣關係圖在本組杜鵑中無解析力。以上親緣關係結果、加上R. rubropilosum的遺傳歧異度最高，再加上共祖時間的計算比較，確認R. rubropilosum為一雜交起源種。
　　利用葉綠體以及多copy的核基因片段，本研究最後將台灣映山紅組的十種杜鵑花歸為四群：第一群包含R. simsii、R. longiperulatum、R. nakaharai、R. kanehirai和R. noriakianum；第二群包含R. taiwanalpinum、R. breviperulatum和
R. lasiostylum；第三群為R. oldhamii；第四群為
R. rubropilosum，此結果與Yamazaki(1996)形態分類研究結果比較，除了R. rubropilosum在本研究中發現為一獨立的雜交起源種之外，其他物種的親緣關係與其形態的歸群結果相吻合，因此配合分子研究的結果，更能詳盡的解釋台灣映山紅組杜鵑花的親緣關係。
　　最後，以本研究結果推測台灣映山紅祖杜鵑花可能有三個以上的來源，但由於未蒐集到此組分布在鄰近地區的物種，所以此推測的證據並不足。未來若想要探討台灣映山紅組杜鵑花的更詳盡的演化歷史，應詳盡蒐集此組杜鵑花所有的物種以及使用，才能更進一步的了解台灣映山紅組杜鵑花起源與分化。

Rhododendron sect. Tsutsusi in Taiwan comprises of 10 species. These species are very similar morphologically and are all endemic except R. simsii. Many examples point out that rapid evolution and subsequent speciation are often occurred on newly formed island. The endemic feature of these species and the newly formed island feature of Taiwan suggest that Rhododendron sect. Tsutsusi in Taiwan may be a result of fast evolution. This study uses cpDNA matK and trnK intron sequences and nuclear DNA RPB2-i intron 2 and ITS sequences to investigate the phylogenetic relationship of these closely related species .
Phylogeny tree constructed by matK and trnK intron sequence shows three major groups; and which constructed by RPB2-i intron 2 sequence shows two major groups. The author discovers that RPB2-i sequences of all species have two copies except R. oldhamii, besides, different copies of
R. rubropilosum are separately grouped into two different groups. However, phylogenetic tree constructed by ITS sequences is not well resolved. From the results above, the highest genetic diversity of R. rubropilosum, and the comparison of coalescent time together, the author infers that R. rubropilosum is a hybrid origin.
Combine the phylogenetic results of cpDNA trnK-matK intron and low copy number RPB2-i intron 2 sequenses, Rhododendron sect. Tsutsusi in Taiwan can be classified into four groups: the first group comprises of R. simsii, R. longiperulatum,R. nakaharai,R. kanehirain, and
R. noriakianum; the second group comprises of
R. taiwanalpinum, R. breviperulatum; and R. lasiostylum; the third group comprises of R. oldhamii; and the last group comprises of R. rubropilosum. Phylogenetic relationship based on molecular data is coincident with the morphological treatment, except R. rubropilosum. Therefore, the results based on molecular data can unmask more inconspicuous information to infer the phylogenetic of Rhododendron sect. Tsutsusi in Taiwan.
Finally, based on the results, the author speculates there may be at least 3 independent origins of these closely related species. However, the author cannot ascertain that the speculation is accurate since the lack of samples of Rhododendron sect. Tsutsusi . Therefore, collecting more samples and using more sensitive markers in the future are necessary to study more about the origin and the divergence of Rhododendron sect. Tsutsusi in Taiwan.

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