Dothistroma needle blight (DNB) caused by the ascomycetous fungus Dothistroma septosporum is an important pine disease in Europe. In this study, we determined the distribution and abundance of D. septosporum in local Scots pine forests and plantations in Lithuania and neighbouring Belarus by combining morphological observations and molecular tools. This is the first valid report on the occurrence of D. septosporum in Belarus, based on detailed morpho‐cultural and molecular characteristics. Currently, in both countries only the asexual stage of D. septosporum is found on needles of the native Scots pine and on various ornamental exotic pines planted in botanical gardens and arboreta. Our results show that P. sylvestris may now be considered the most common host with varying susceptibility to D. septosporum. Phylogenetic analysis revealed the presence of three different ITS haplotypes among Lithuanian and Belarusian D. septosporum isolates. Mating type (MAT) genes analysis showed that two mating types (MAT1‐1 and MAT1‐2) occur in both countries, indicating a high probability of D. septosporum sexual reproduction. Isolates from Lithuania were represented by the idiomorph MAT1‐1 and MAT1‐2 in the ratio of 1:1, while isolates from Belarus were dominated by the idiomorph MAT1‐1 (ratio 3:1). Our results also demonstrate the importance of DNB monitoring for prevention and control of disease outbreaks in Lithuanian and Belarusian Scots pine forests in the future.

中文翻译：

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立陶宛和白俄罗斯发生Dothistroma针叶枯病的风险：原生苏格兰松树森林的风险

造成子囊菌Dothistroma针疫病（DNB）Dothistroma septosporum是一个重要的松树病害的欧洲。在这项研究中，我们结合形态学观察和分子工具，确定了立陶宛和邻近白俄罗斯的苏格兰松树松林和人工林中D. septosporum的分布和丰度。根据详细的形态文化和分子特征，这是第一份关于白俄罗斯破壁孢霉发生的有效报告。目前，在这两个国家中，仅在天然苏格兰松树的针叶上以及在植物园和树木园中种植的各种观赏奇异松树上都发现了D. septosporum的无性繁殖期。我们的结果表明，樟子松可能现在被认为是最常见的宿主，对鸡丝孢菌的敏感性不同。系统发育分析表明，立陶宛人和白俄罗斯D. septosporum分离物中存在三种不同的ITS单倍型。交配类型（MAT）基因分析表明，两个国家都有两种交配类型（MAT1-1和MAT1-2），这表明葡萄球菌有性繁殖的可能性很高。来自立陶宛的分离株以1：1的独特形态MAT1-1和MAT1-2代表，而来自白俄罗斯的分离株则以独特的MAT1-1（比例3：1）为主。我们的结果还证明了DNB监测对于预防和控制立陶宛和白俄罗斯苏格兰苏格兰松树林中疾病暴发的重要性。