香榧品种遗传变异与品种鉴定的ISSR分析

Genetic Variation and Fingerprinting of Torreya grandis Cultivars Detected by ISSR Markers

利用ISSR方法对香榧本地9个实生品种和8个优良无性系的遗传变异和品种间的遗传关系进行了分析,从50个随机引物中筛选出12条多态性引物用于正式扩增,共扩增出104个DNA片段,其中88个片段为多态性扩增片段,占总扩增片段的84.6%。根据ISSR引物的扩增图谱,确定部分供试品种的特异条带。基于Neis遗传距离分析,利用UPGMA法构建了分子树状图。聚类结果把供试的香榧9个实生品种和8个优良无性系分为两大组,第一组包括大圆榧、米榧、旋纹榧、獠牙榧、芝麻榧、落霜榧、象牙榧,第二组包括小圆榧、茄榧和细榧优良无性系。

Inter-simple sequence repeat （ISSR） was used to determine the genomic DNA variations and relationships in Torreya grandis Fort. Seventeen individuals including 9 cultivars and 8 elite clones were used in ISSR analysis. Of the 50 ISSR primers subjected to screening, 12 produced reproducible, polymorphic and disc-repant fragments. Using these primers, 104 DNA bands were amplified, of which 84.6% were polymorphic. The average number of DNA bands amplified by each primer was 11. DNA profiles based on ISSRs have revealed potential diagnostic for various individual accessions. A dendrogram generated using the Unweighted Pair Group Method with Arithmetic Average based on Nei＇s distance showed that the Torreya grandis cultivars were clustered into two groups. The first group included Dayuanfei, Mifei, Xuanwenfei, Liaoyafei, Zhimafei,Luoshuangfei and Xiangyafei, the second group included Xiaoyuanfei, Qiefei and the clone cultivars of Torreya grandis ‘Merrillii’.