观赏石榴品种的ISSR遗传关系与DNA指纹研究

Study on Genetic Relationship and DNA Fingerprint of Ornamental Pomegranate Cultivars Based on ISSR Markers

以42个观赏石榴品种为试材,采用ISSR标记法,研究了42个品种的遗传关系与指纹图谱,以期为观赏石榴种质资源的品种鉴定、杂交育种和开发利用等提供参考依据。结果表明:16条引物产生327个位点,其中279个是多态位点,平均引物多态性比率为85.32%,说明所选引物多态性较好。42个石榴品种间遗传相似系数(GS)为0.46~0.98,说明观赏石榴品种的遗传多样性较为丰富。当遗传相似系数阈值为0.629时,可以将42个品种分为四大类,分类结果与按照形态学分类不一致,与品种地理来源无明显相关性。通过研究引物和引物组合对42个品种的聚类区分率构建DNA指纹,16条单引物的品种区分率为16.67%~88.10%,16条引物均不能将全部品种区分开。引物组合UBC835/UBC827对42个品种的最大遗传相似系数为0.97,品种区分率达100.00%,将引物组合UBC835/UBC827产生的DNA谱带作为42个观赏石榴品种的DNA指纹图谱。

The genetic relationship and DNA fingerprint of 42 ornamental pomegranate cultivars were studied by ISSR markers in this study,in order to provide reference for breeding and utilization of ornamental pomegranate.The results showed that a total of 327 bands were amplified from 16 ISSR primers with good polymorphism,of which 279 were polymorphic loci.The average polymorphic ratio of the primers was 85.32%.The genetic similarity coefficient between 42 cultivars was from 0.46 to 0.98 that showed the genetic diversity of 42 ornamental cultivars was relatively rich.The clustering results by UPGMA showed that 42 cultivars could be divided into four groups at GS 0.629.The clustering results by ISSR marker did not accord with the classification results based on morphological method and geographical origin.The cultivar distinguish rate of 16 primers ranged from 16.67%to 88.10%,so 16 single primers could not distinguish all cultivars.The maximum genetic similarity coefficient(GS)of UBC835/UBC827 combination between cultivars was 0.97 and the distinguish efficiency for 42 cultivars was 100.00%.Therefore the DNA bands form primer combination UBC835/UBC827 were used to construct the DNA fingerprint of 42 ornamental pomegranate cultivars.