During 2017, Dutch elm disease was investigated on 67 Ulmus glabra and 29 Ulmus laevis samples from 28 sites in Latvia. The presence of Ophiostoma novo‐ulmi was detected in 61.2% of the samples from U. glabra and in 34.5% of the samples from U. laevis. In 11% of cases, hybrids between subsp. novo‐ulmi and subsp. americana were identified, particularly in the sites in the southern part of Latvia. This study presents the first verified record of Ophiostoma novo‐ulmi and its subspecies in Latvia.

中文翻译：

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来自拉脱维亚的荷兰榆树病病原菌新口疮的首次报道

2017年期间，对来自拉脱维亚28个地点的67头Ulmus glabra和29头Ulmus laevis样本进行了荷兰榆病调查。在U. glabra的61.2％和U. laevis的34.5％的样品中检出了新的Ophiostoma noul-ulmi。在11％的情况下，亚种之间杂交。新乌尔米和亚种 确定了美洲树，特别是在拉脱维亚南部的遗址。这项研究提出了拉脱维亚新口蹄疫及其亚种的第一个验证记录。