Genetic Diversity of Balanophora fungosa and Its Conservation in Taiwan

台灣產粗穗蛇菰之遺傳變異與保育

蕭淑娟(Shu-Chuan Hsiao) ； 黃煒珽(Wei-Ting Huang) ； 林茂森(Maw-Sun Lin)

《Botanical Studies》 51卷2期 (2010/04) Pp. 217-222

摘要

粗穗蛇菰在台灣是一種稀有的全寄生性開花植物，其分布點局限於台灣南端恆春半島、以及位於台灣島東南外海的火山島－蘭嶼。在此兩地區的粗穗蛇菰可依花序的顏色分為兩群：恆春群為黃色；蘭嶼群為橘紅至紅色。本研究利用簡單重複序列間區(ISSR)之分子標記法以及不加權平均法(UPGMA)以分析粗穗蛇菰族群間的遺傳變異。結果顯示：兩地區的族群之Dice相似度高達0.78，支持其為同一物種；且地區間、地區內之族群亦有明顯分群。分子變方分析(AMOVA)顯示以地區分群之變方成分佔31.35%；群內之族群間佔13.74%；而族群內則佔54.91%，明顯指出其遺傳變異主要發生在族群內的個體之間。而在遺傳距離成對相較下，兩地區的族群亦顯示出分化的情形（其遺傳距離在0.44~0.53之間）。因此，我們建議在恆春半島的墾丁公園及蘭嶼的粗穗蛇菰棲地應分別設立保護區，使此稀有植物的族群可在無人為干擾下自然擴展。

關鍵字

粗穗蛇菰 ； 保育 ； 族群變異

並列摘要

Balanophora fungosa is a rare holoparasitic flowering plant in Taiwan, where it is restricted to the Hengchun Peninsula in southernmost Taiwan, and Orchid Island (Lanyu in Chinese), a small volcanic island off the southeastern coast of Taiwan. Plants from these two areas appear in two different groups based on the color of the inflorescence, i.e., those of Hengchun are yellow, but they are pinkish orange to red on Orchid I. This study used an inter-simple sequence repeat (ISSR) molecular marker approach and the unweighted pair group method with arithmetic mean (UPGMA) analysis to evaluate genetic variations among populations of B. fungosa. The results showed that the two geographical groups represent the same species as indicated by a high Dice similarity value of 0.78. Populations from the two areas formed two well-defined clusters, as did populations within each area. The results of the analysis of molecular variance (AMOVA) showed that the components of variation between groups (31.35%), among populations within groups (13.74%), and within populations (54.91%) were significant (p＜0.001), indicating that variations among individuals within populations contributed most to the total genetic variance. The populations of the two areas were also differentiated with genetic distances ranging from 0.44~0.53 for paired comparisons. Therefore, we recommend that protected areas be set aside in both areas for B. fungosa, that is, in Kenting Park on the Hengchun Peninsula and on Orchid Island, to allow the population to expand naturally without human disturbance.

並列關鍵字

Balanophora fungosa ； Conservation ； Population variation