豫南烟区烟草青枯病菌的致病力及遗传多样性分析

Analysis of Pathogenicity and Genetic Diversity of Ralstonia Solanacearum on Tobacco in Southern Henan Province

为有效防控豫南烟区烟草青枯病,对来自信阳市罗山县、驻马店市确山县和遂平县的烟草青枯病菌的致病力和遗传多样性进行了测定分析。人工接种试验表明,豫南烟区烟草青枯病菌的致病力分为强、中和弱3种,不同寄主来源的烟草青枯病菌具有显著的致病力差异。从100个随机引物中筛选出8个扩增条带清晰且具有丰富多态性的引物用于不同地区烟草青枯病菌菌株DNA的RAPD分析,共扩增出720条带,其中多态性带占88.9%。聚类结果和遗传相似系数分析显示,供试菌株可分为A、B两大类,遗传相似系数范围为0.49~1.00,且供试菌株间的遗传相似性与其地理来源有一定的相关性。综上所述,豫南烟区烟草青枯病菌的致病力存在明显差异且其DNA具有丰富的遗传多样性。

In order to take effective measures to control tobacco bacterial wilt in Henan Province, the pathogenicity and geneticdiversity of R alstonia solanacearum from tobacco in Luoshan, Queshan and Suiping counties of Henan Province were investigated.The results showed that all the isolates could be divided into three pathogenic types including strong, medium and week pathogenicityby artificial inoculation. Also, the R. solanacearum strains from different hosts showed significant difference in pathogenicity. Eightprimers which were screened from 100 primers were used in RAPD analysis of R. solanacearum Isolates. A total of 720 bands wereobtained and 88.9% of them were polymorphic. Based on clustering and similarity analysis, the tested isolates fell into two groups andthe genetic similarity among different strains was from 0.49 to 1.00. Moreover, the genetic similarity might be related to differentgeographical origin. In summary, the R. solanacearum isolates infecting tobacco in southern Henan Province showed obviousdifferentiation of pathogenicity with abundant genetic diversity.