(56(4):281-288)Using RAPD Markers to Study Genetic Variation among Lychee Cultivars

以十三個荔枝品種爲材料，進行RAPD的片段分析。經篩選200個逢機引子後，選出23個引子所產生的259個條帶(RAPD markers)，做爲十三個荔枝品種間的親緣關係評估之依據。並利用Jaccard氏的計算方法，求得不同樣品間的相似度；並利用UPGMA方法，建立其親緣關係圖。結果顯示參試的十三個荔枝品種可區分爲兩大群，其中玉荷包與三月紅最爲相似，並與竹葉、新興、糖薄、高雄早生等品種叢聚在指數0.53處，而沙坑小核、尚書淮、糯米滋、桂味、桂枝及黑葉等品種則成另一叢聚在指數0.52處，其中桂味與桂枝的相似度100%，顯示這兩個品種可能爲同種異名。另外，就引子所產生條帶數而言，在23個引子中，以UBC-199產生9個條帶數爲最少，其次爲OPE-06及OPG-01產生10個條帶數，而OPG-08產生26個條帶數爲最多，平均每個引子可以產生15個條帶，從這些引子中篩檢出鑑別玉荷包品種的專一性條帶7條、鑑別糯米滋品種的專一性條帶6條、鑑定沙坑小核品種的專一性條帶7條、及鑑定高雄早生品種的專一性條帶6條、一個尚書淮品種的專一性條帶、四個新興品種的專一性條帶、一個竹葉品種的專一性條帶及兩個桂味及桂枝品種共有的專一性條帶，這些品種專一性的條帶將可供作不同荔枝品種鑑別用。The random amplified polymorphic DNA (RAPD) markers were used to identify the genetic relationship among introduced lychee cultivars in this study. Among 200 different decamer primers, 23 primers were selected; the selected primers amplified a total of 259 DNA bands. The total number of amplified bands per primer varied from 9 (UBC-199) to 26 (OPG-08), on an average 11.3 bands were induced by each primer. Jaccard's similarity coefficients for interval measure within and between cultivars were used to produce a cluster diagram using the unweighted pair-group method (UPGMA). The results showed that eighteen samples from thirteen lychee cultivars could be divided into two major groups: one included Yu ho pao, San yue hong, Zhu yeh, Xin xing, Liu yue xue, Tang bo and Gao xiong zao sheng; the other included Sha keng xiao ho, Shang shu huai, No mi zi, Kwai wei, Kwai zi and Hei yeh. The Jaccard's similarity coefficient of Kwai wei and Kwai zi was 1.00, implying that Kwai wei and Kwai zi may be the same cultivar. From 259 RAPD marker bands, we discovered 8 specific bands for Yu ho pao, 6 for No mi zi, 7 for Sha keng xiao ho, 6 for Gao xiong zao sheng, 1 for Shang shou huai, 4 for Xin xing, 2 for Hei yeh, 1 for of Zhu yeh and 2 for Kwai wei (Kwai zi). Those specific single bands of different cultivars will be recovered from agarose gel and cloned into TA vector system for sequencing, in order to develop new specific primer sets for the use of identifying different cultivars and hybrid posterity