Common scab is an important disease of potato caused by Streptomyces scabies and other closely related species. In this study, the genetic diversity of Streptomyces spp. causing common scab of potato in eastern Canada was for the first time investigated. Forty-one Streptomyces spp. isolates were retrieved from necrotic lesions of potato tubers harvested from different regions of the Canadian provinces New-Brunswick, Nova Scotia and Prince-Edward-Island. Most isolates were closely related to known pathogenic S. scabies strains on the basis of partial 16S ribosomal (r) RNA and rpoB gene sequence analyses. Two isolates were identified as pathogenic species of Streptomyces acidiscabies. To our knowledge, this species has never been previously isolated in these areas. Genome fingerprinting studies using repetitive elements (rep) polymerase chain reactions (PCR) revealed 10 distinct genetic groups in eastern Canada. The geographical distribution of the genetic groups was region-dependant. Pathogenicity- and virulence-related genes (txtA, txtC, and tomA) were PCR-amplified from each isolate, and nucleotide sequence analysis of partial gene fragments revealed slight polymorphisms in both txtA and txtC genes. No genetic variation was noted in the partial tomA gene sequences.

中文翻译：

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链霉菌的遗传多样性。在加拿大东部引起马铃薯的常见结sc。

普通sc疮是由链霉菌sc疮和其他密切相关物种引起的马铃薯重要疾病。在这项研究中，链霉菌的遗传多样性。首次调查了导致加拿大东部马铃薯常见结sc的原因。四十一链霉菌属。从加拿大新不伦瑞克省，新斯科舍省和爱德华王子岛省不同地区收获的马铃薯块茎坏死病灶中提取分离株。根据部分16S核糖体（r）RNA和rpoB基因序列分析，大多数分离物与已知的致病性S疮链球菌菌株密切相关。确定了两个分离株为酸性链霉菌的致病菌。据我们所知，该物种以前从未在这些地区被隔离过。基因组指纹图谱研究使用重复元件（rep）聚合酶链反应（PCR）揭示了加拿大东部的10个不同的遗传群体。遗传群体的地理分布取决于区域。从每个分离株中PCR扩增出与致病性和毒力相关的基因（txtA，txtC和tomA），对部分基因片段的核苷酸序列分析发现txtA和txtC基因均存在轻微的多态性。在部分tomA基因序列中未发现遗传变异。对部分基因片段的核苷酸序列分析表明，txtA和txtC基因均存在轻微的多态性。在部分tomA基因序列中未发现遗传变异。对部分基因片段的核苷酸序列分析表明，txtA和txtC基因均存在轻微的多态性。在部分tomA基因序列中未发现遗传变异。