應用ISSR標誌評估沙漠玫瑰品種之遺傳變異

Evaluation of Genetic Variation of Desert Rose (Adenium) Cultivars with Inter Simple Sequence Repeat (ISSR) Markers

本試驗以35個沙漠玫瑰栽培品種為材料，利用ISSR分子標誌進行DNA指紋資料庫之建立及遺傳相似性分析。試驗結果顯示，可產生訊號較強多型性條帶的15個核酸引子，獲得161條帶，平均每一引子可得條帶為10.7條。分析使用之15條核酸引子序列，發現3’-anchored primer之擴增效果較佳，以2個鹼基之簡單重複序列為主。所得之指紋分析資料經Jaccard遺傳相似性係數運算，得各樣品間的遺傳相似性介於0-88%之間，所有樣品間之平均遺傳相似性為44.35%。依據未加權算術平均法（UPGMA）進行群聚分析，繪製出樹狀分枝圖。若依遺傳距離0.40作為分群依據，可將所有樣品分成4個主要群組。品種差異較大的哈利波特成為個別獨立的1群（I）；第II、III群分別包含2、6個品種；第Ⅳ群包含品種最多，可再分成2小群，其中1小群為3個阿拉伯引進種；另1小群為泰、美引進及其相關的台灣育種品種。在所選用的35個沙漠玫瑰栽培種中，阿拉伯引進種間的遺傳相似性較高，而與泰國、美國引進種或以其當親本所得的栽培種分離開來。‘花中花’與其自交所產生的子代幾乎完全相似（88.04%）。 In this study, 35 desert rose variety were evaluated using ISSR (inter simple sequence repeat) molecular markers. The samples comprised 3 clones of Arab, 7 clones of Thailand, 2 clones of America, and 23 hybrid clones between Thailand and America. Objectives were to assess genetic similarity among the varieties. There were 161 polymorphic bands produced by 15 selected ISSR primers. The result of ISSR suggested that among the dinucleotides motifs, the poly(AC)n motif was more abundant and gave the largest number of polymorphism. Genetic similarity among 35 samples was detected from 0% to 88% on ISSR marker basis. The cluster analysis of genetic similarity by UPGMA (Unweighted Pair-group Mean Arithmetic) revealed that four major groups could be recognized. The 3 clones of Arab had larger genetic similarity than others, thus they composed a small group in the clustering tree.