台灣及鄰近地區樟樹之族群遺傳變異 The genetic variation of Cinnamomum camphora populations distributed around Taiwan

本研究用ISSR分子標誌檢測台灣及鄰近地區的樟樹族群遺傳結構，並以NTSYS進行群團分析及主成分分析，以POPGENE及AMOVA軟體分析其族群結構及變方。採自樟樹分布區域內之代表族群，分析結果顯示台灣地區之樟樹與中國大陸地區之樟樹大致形成2個群團，再與恆春半島地區之種源聯結，最後才與日本琉球地區石垣島之樟樹聯結。主成分分析亦區分成4個群團：中國大陸產樟樹、台灣產樟樹、恆春半島產樟樹(即栳樟)、日本琉球產樟樹。產自台東縱谷的樟樹與台灣其他地區的樟樹接近，而與恆春半島產者不同，因此，台東縱谷的樟樹非栳樟。變異數分析（AMOVA）顯示中國大陸產、台灣產與日本石垣島產之樟樹區域間的變方成分為45.4％，而區域內族群間之變方成分為26.6 ％，族群內個體間的變方成分為28.0％。不分區域之族群間的變方成分(66.5%)，二倍於族群內個體間的變方成分(33.5%)。樟樹種內的遺傳歧異度為0.256，族群分化係數（Gst）為0.488，基因流轉（Nm）的數值為0.524。由於基因流的數值低於1，可見兩岸之樟樹族群間存有交流障礙。

ISSR techniques were used to analyze genetic variation of regional Cinnamomum camphora , including populations from whole Taiwan Island, South China and Okinawa of Japan. The results, according to NTSYS cluster and PCO analyses, indicated that 4 groups of C. camphora populations were formed, including Taiwan, China, Okinawa of Japan and Hengchun Peninsula. NTSYS cluster showed that Taiwan group linked first with China group, and then with Hengchun Peninsula and Okinawa groups. Variation component of the species among the areas of Taiwan, China and Okinawa was 45.4% while among population within region was 26.6% and among individual within populations was 28.0%. POPGENE analysis showed that genetic diversity of the species was 0.256, Gst 0.488, Nm0.524, indicating that gene flow barrier existed among Taiwan, China and Okinawa.