Pyrenophora tritici-repentis (Ptr), family Pleosporaceae, is a common wheat pathogen in all wheat-growing regions around the globe. It is widely studied in North America, South America, and North Africa, while data about the fungus genetic diversity in Europe is still insufficient. This study aimed to describe the variation of morphological traits and toxin production of strains collected in Latvia and Belarus. Twenty-one isolates from Latvia, and 12 from Belarus were sampled in 2019 for morphological evaluation in culture and necrotrophic effector gene determination by PCR. All isolates were grouped into nine different morphotypes. Five of these morphotypes were unique for isolates from Latvia, one for Belarus, and three morphotypes were occurring in both countries. No association between the host and the pathogen morphotype was observed. ToxA gene was detected in 44% of the analysed isolates. For 52% of the isolates, PCR did not confirm the presence of any known effector genes of Pyrenophora tritici-repentis. ToxB and toxb were found only in one isolate from Latvia. The studies need to be continued to evaluate the diversity of the pathogen depending on the host species.

Pyrenophora tritici-repentis ( Ptr )，Pleosporaceae 科，是全球所有小麦种植区常见的小麦病原菌。它在北美、南美和北非被广泛研究，而欧洲关于真菌遗传多样性的数据仍然不足。本研究旨在描述在拉脱维亚和白俄罗斯收集的菌株的形态特征和毒素产生的变化。2019 年对来自拉脱维亚的 21 株分离株和来自白俄罗斯的 12 株分离株进行了取样，用于培养形态学评价和通过 PCR 测定坏死性效应基因。所有分离物被分为九种不同的形态类型。其中五种形态型是拉脱维亚分离株独有的，一种是白俄罗斯独有的，这两个国家都出现了三种形态型。没有观察到宿主和病原体形态类型之间的关联。毒素A在 44% 的分析分离物中检测到基因。对于 52% 的分离株，PCR 未证实存在任何已知的Pyrenophora tritici-repentis效应基因。ToxB和toxb仅在来自拉脱维亚的一种分离物中发现。需要继续进行研究，以根据宿主物种评估病原体的多样性。