条斑紫菜6个品系的SRAP分析

为鉴别条斑紫菜不同品系的种质,使用相关序列扩增多态性(sequence-related amplified polymorphism,SRAP)标记对条斑紫菜的5个选育品系和1个野生品系进行遗传分析,结果从35对引物组合中筛选出可扩增出稳定清晰条带的组合11对,共获得131个扩增位点,其中多态性位点125个,多态性比例高达95.42%。6个品系 间的遗传距离为0.364 3～0.867 9,平均为0.593 0。用UPGMA法进行聚类分析,结果将6个品系分为2个群,所反映的亲缘关系与各品系的来源基本一致,说明SRAP 标记技术可以成为条斑紫菜品系间遗传分析的有效工具。在131个多态性位点中,选择扩增出的4个位点构建了6个品系的指纹图谱。另外,通过ME1/EM6引物组合 扩增得到耐高温品系TM-18的特异性条带,经回收测序和重新设计引物,该条带在其丝状体和叶状体DNA中均能稳定地被扩增出来,可用于该品系的种质鉴别 。

Analysis and identification of different strains of Pyropia yezoensis using sequence-related amplified polymorphism markers

6 strains of Pyropia yezoensis (Ueda)M.S.Hwang et H.G.Choi were analyzed using SRAP(sequence-related amplified polymorphism)markers in order to identify the germplasm.DNAs from conchocelis of 6 strains were screened with 35 primer combinations,of which 11 primer combinations gave stable and reproducible amplification patterns.Among the total 131 fragments,125 fragments(95.42%)were polymorphic.The genetic distances of 6 strains were between 0.364 3 and 0.867 9,and the average was 0.593 0.Cluster analysis of UPMGA showed a good and true relationships among the 6 strains.The results demonstrated that SRAP could be a useful tool in germplasm identification of P.yezoensis strains.From the total 131 fragments,4 fragments amplified by 1 primer combination were used to develop the DNA fingerprints of 6 strains of P.yezoensis.One specific fragment of TM-18 was obtained in the fragments amplified by primer combination ME1/EM6.According to the DNA sequence of the fragments,a specific pair-primer was designed and it achieved stable amplification of a 340 bp specific band in both DNA of conchocelis and blades of TM-18.The specific marker could be used in fast identification of TM-18 strain.