我国北方马铃薯主产区致病疫霉群体遗传结构分析

Analysis of Population Genetic Structure of Phytophthora infestans from Main Potato Production Areas in Northern China

将细胞核染色体DNA和细胞质线粒体DNA遗传多态性相结合,利用SSR分子标记和以PCR为基础的线粒体单倍型测定技术,对我国北方5个省(区)的82株致病疫霉群体的分子遗传多样性进行了测定与评价。结果表明,82株供试致病疫霉中发现G-01—G-18等18个SSR基因型和ⅠR3、ⅡR3、ⅠR1、ⅡR2、ⅠR25种线粒体单倍型。华北、东北和西北3个地区的致病疫霉各具有其优势SSR基因型,分别为G-01、G-04和G-18。除宁夏外,河北、黑龙江、吉林和内蒙古各省(区)又分别具有几个独特的SSR基因型。ⅠR3、ⅡR3和ⅠR1为供试菌株中主要的线粒体单倍型。华北与东北地区的致病疫霉以R3型为主,而西北地区则以R1型为主。Ⅰ型和Ⅱ型在华北和东北地区比例相差不大,而在西北地区除1株菌株为Ⅱ型外,其余均为Ⅰ型。这表明我国北方马铃薯主产区致病疫霉群体存在着较为丰富的遗传多样性,且其多样性与地理来源密切相关。

Genetic diversities of 82 Phytophthora infestans isolates in northern China were examined and evaluated by SSR molecular markers from nucleus chromosomal DNA and mitochondrial haplotypes from cytoplasm mitochondrial DNA. The results showed that 18 SSR genotypes （from G-01 to G-18） in 9 loci with high polymorphisms were discovered and 5 mitochondrial haplotypes （i. e. Ⅰ R3,Ⅱ R3, Ⅰ R1, Ⅱ R2 and I R2） were also detected in 82 P. infestans isolates from northern China. The dominant SSR geno- types of P. infestans in North, Northeast and Northwest China were G-01, G-04 and G-18,respectively. P. infestans from three provinces i. e. Hebei, Heilongjiang,Jilin, and Inner Mongolia Autonomous Region had their distinctive SSR genotypes except Ningxia Hui Autonomous Region. Ⅰ R3, Ⅱ R3 and Ⅰ R1 were major mitochondrial haplotypes of the tested isolates. Type R3 was major in North and Northeast China,however, type R1 was major in Northwest China. Types Ⅰ and type Ⅱ had similar proportion in North and North- east China,however,type Ⅰ was majority in Northwest China. The molecular data showed that genetic di- versities of P. infestans population from main potato production areas in northern China were rich, andtheir diversities were closely related to geographical origin.