Bacterial canker of stone fruit is a destructive disease of Prunus species. Here we characterized five Pseudomonas syringae (Ps) strains isolated from bacterial cankers of stone fruits in East Azerbaijan province, Iran. Koch’s postulates were performed demonstrating pathogenicity on apricot cuttings. Ice-nucleation activity and syringomycin synthesis were determined phenotypically and confirmed molecularly in all five strains. Strains were variably resistant to copper. The strains were then compared to a sample of 227 strains of the Ps species complex using multilocus sequence analysis (MLSA) of the four housekeeping genes gap1, gltA, gyrB, and rpoD. The concatenated sequences of the four genes provided a deeply-resolved phylogeny. Iranian strains all belonged to Ps phylogroup 2 but clustered into three separate sub-groups. They had the greatest similarity to strains isolated from stone fruit trees in the USA, UK, and Lebanon but also to strains isolated from other plant species and the water cycle. We conclude that canker of stone fruit is caused by a diverse group of Ps phylogroup 2 strains with global distribution. Further sampling, host range testing, and genome sequencing will be needed to get further insight into the relative role of the water cycle and other modes of long distance movement in the dissemination of Ps strains that cause bacterial canker of stone fruit.

核果的细菌性溃疡是李属物种的毁灭性疾病。在这里我们的特点5丁香假单胞菌（诗在东阿塞拜疆省，伊朗核果的细菌溃疡病隔离）菌株。进行了科赫的假设，证明了杏cutting插的致病性。表型测定冰成核活性和丁香霉素的合成，并在所有五个菌株中分子测定。菌株对铜具有不同的抗性。然后使用四个管家基因gap 1，glt A，gyr B和g的多基因座序列分析（MLSA）将菌株与Ps物种复合体的227个菌株的样品进行比较。rpoD。这四个基因的串联序列提供了深度解析的系统发育史。伊朗菌株均属于Ps phylogroup 2，但聚集成三个独立的亚组。它们与从美国，英国和黎巴嫩的核果树中分离的菌株最大相似，但也与从其他植物物种和水循环中分离的菌株最大相似。我们得出结论，核果的溃疡病是由具有全球分布的一组不同的Ps phylogroup 2菌株引起的。需要进一步的采样，寄主范围测试和基因组测序，以进一步了解水循环和其他长距离运动模式在导致核果核病的Ps菌株传播中的相对作用。