利用ISSR DNA標誌評估台灣菊花品種之遺傳變異

Evaluation of Genetic Variation of Chrysanthemum (Dendranthema×morifolium Ramat.) Varieties with Inter Simple Sequence Repeat DNA Markers

本實驗針對16個夏菊品種及16個秋菊品種，進行ISSR DNA標誌分析，建立DNA指紋資料庫，評估菊花品種間之遺傳相似性。結果夏菊用14條核酸引子可產生132個條帶，其中包含126條多型性之條帶，平均每一引子可產生9.4個條帶。以16個夏菊品種所得條帶經Jaccard's遺傳相似性係數分析，呈現品種間相似性介於0.29~0.77之間，平均相似性為0.43。依遺傳相似係數0.43作為分群依據，可將16個夏菊品種分成3群，其中耐熱型品種間的相似性高達0.70以上。秋菊用14個核酸引子共產生127個條帶，其中包含124個多型性條帶，平均每一引子可產生9.1個條帶。此16個秋菊品種間相似性介於0.23~0.53之間，平均相似性為0.32。依遺傳相似係數0.32作為分群依據，則可將16個秋菊品種分成2大群。本實驗篩選到的14個核酸引子中，有12個為3'-anchored的核酸引子，兩個為5'-anchored的核酸引子，其中（CA）n序列有4個，（AC）n序列有3個，顯示菊花基因體內可能存在較多量的（AC）n序列。 The genetic variation of 32 chrysanthemum (Dendranthema×morifolium Ramat.) varieties, 16 each for summer and autumn chrysanthemums, were evaluated by using Inter Simple Repeat (ISSR) DNA markers. We found 132 bands including 126 polymorphic bands in summer cultivars when analyzed wish 14 ISSR primers. The average number of band is 9.4 per primer. The genetic similarity among these 16 cultivars was 0.29 to 0.77, averaged at 0.43. Similar analysis revealed 127 bands including 124 polymorphic bands in autumn cultivars. The genetic similarity for autumn cultivars was 0.23 to 0.53, averaged at 0.32. Cluster analysis using Un-weighted Pair-group Mean Arithmetic (UPGMA) revealed that there are three major groups in summer chrysanthemums. The heat-tolerant varieties has a similarity value ＞0.70. Two major groups were recognized in autumn cultivars. The results of ISSR analysis suggested that dinucleotede poly (AC) n motifs were more abundant and they gave more polymorphic bands.