不同地区辣椒疫霉菌遗传多样性的RAPD分析

Phylogenetic analysis among isolates of Phytophthora capsici from di fferent areas by RAPD

通过利用12个十碱基随机引物对来自我国7个不同地理区域的56个辣椒疫霉菌株进行RAPD分析,探索了我国主要辣椒种植区间的辣椒疫霉菌的遗传分化关系。结果表明:1)受试56个菌株共产生70条谱带,其中多态性为56条,占80%,说明我国主要辣椒种植区的辣椒疫霉菌具有较丰富的遗传多样性;2)根据引物扩增的DNA指纹图谱,运用UPGMA分析法,以遗传相似系数0.6为阈值,将供试56个菌株划分为8个基因型(I、II、III、IV、V、V I、V II、V III),发现除少数来自相近地理海拔的绝大多数菌株被划分为同一个基因型外,其它不同地理区域的菌株基因型的划分与地理来源无直接的关系。在此基础上,结合我国不同地理区域辣椒疫霉病发生情况,提出我国辣椒疫霉菌基因型的划分除少数与地理区域有关外,其它绝大多数地区的辣椒疫霉菌基因型的划分与地理来源无直接的相关性。

Genomic fingerprints of 56 strains of P. capsici from different pepper cultivated areas were analyzed by using 12 RAPD primers. The genetic distance and the genetic relationships of the accessions were reconstructed by using UPGMA （Unweigthted Pair-Group Method with Anthmetic average） cluster analysis. The result of the RAPD fingerprints showed that the polymorphism exists among different strains. And all strains were divided eight genotypes. A few of isolates came from close geographical altitude were divided into the same genotype. However, the division of isolates from other different areas is not related to the origination. According to the occurrence situation of the blight of pepper in China, this study confirmed that most of the genotypes of being tested isolates were not obviously related to localities, climate and planting style, except for small number isolates were connected with all those factors.