【摘要】 为明确宁夏回族自治区（简称宁夏）马铃薯炭疽病的发生情况及其病原菌种内的遗传差异及亲缘关系，在宁夏马铃薯主要种植区开展炭疽病调查，同时从宁夏、新疆、青海等省区采集疑似感染炭疽病马铃薯植株进行病原菌分离及鉴定，采用简单重复序列区间（inter-simple sequence repeat,ISSR）分子标记技术对宁夏马铃薯炭疽病病原菌群体的遗传结构特征进行分析。结果显示：宁夏全区均有马铃薯炭疽病发生，且不同种植区马铃薯炭疽病的严重度及发病率均不同。从宁夏、新疆、青海等省区共采集到疑似感炭疽病的马铃薯标本202份，从中分离到28株菌株；通过形态学鉴定、分子生物学鉴定和致病性测定，最终将马铃薯炭疽病病原菌鉴定为球炭疽菌Colletotrichum coccodes；从宁夏分离到的球炭疽菌与从新疆维吾尔自治区分离到的球炭疽菌亲缘关系近，而与从青海省分离到的球炭疽菌亲缘关系远；球炭疽菌的遗传相似性与其地理来源有一定的相关性，分离自同一地方的菌株遗传相似性系数大，遗传距离小，亲缘关系近，反之则遗传相似性系数小，遗传距离大，亲缘关系较远。表明宁夏马铃薯炭疽病病原菌存在着丰富的遗传多样性。更多还原

【Abstract】 In order to clarify the occurrence and etiology of potato black dot disease in Ningxia Hui Autonomous Region, China, investigations of this disease were carried out in the main potato planting areas of Ningxia, and the plants suspected of being infected were collected from Ningxia, Xinjiang and Qinghai provinces/regions for pathogen isolation and identification with the population genetic structure characteristics of the pathogenic fungus causing potato black dot in Ningxia being analyzed by using inter-simple sequence repeat(ISSR) molecular marker technology. The results showed that potato black dot occurred throughout the Ningxia region, with varying severity and incidence rates of the disease across different ecological zones. A total of 202 suspected disease samples were collected from Ningxia, Xinjiang and Qinghai, from which 28 fungal strains of were isolated. Through morphological observation, molecular biological identification and pathogenicity test, the pathogen of potato black dot was finally identified as Colletotrichum coccodes. The C. coccodes strains isolated from Ningxia had a close genetic relationship with those from Xinjiang, but a distant genetic relationship with those from Qinghai. There is a certain correlation between the genetic similarity of C. coccodes and the geographical origin of the strains. Strains isolated from the same place have a higher genetic similarity, smaller genetic distance, and closer genetic relationship. Conversely, strains isolated from different places have a lower genetic similarity, larger genetic distance, and farther genetic relationship. The results indicates that rich genetic diversity exists in potato black dot pathogens.更多还原