Аңдатпа
From 2014 to 2024, soybeans have been the most popular crop in Kazakhstan's agriculture, especially in the northern grain-growing regions. However, in terms of the yield of this crop, Kazakhstan lags behind the largest-producing countries because of the spread of diseases caused by fungi, which lead to lower yields and seed quality. Therefore, the main objective of the study was to identify fungal pathogens affecting soybean crops in the forest-steppe zone of North Kazakhstan, with a focus on isolating and characterizing strains of the Alternaria genus. To identify the fungal strains, the method of determining the direct nucleotide sequence of the internal transcribed spacer region was used, followed by the determination of the nucleotide identity with sequences deposited in the international GenBank database, as well as the method of constructing phylogenetic trees with nucleotide sequences. Fungal isolates were obtained from infected soybean tissues, cultured on potato dextrose agar, and identified through direct sequencing of the ITS region and partial sequencing of the TEF-1α and Tub2 genes, followed by BLAST analysis and phylogenetic tree construction. As a result of the analyses, the authors identified a phytopathogenic strain of Alternaria tenuissima. The analyses revealed that the isolates belonged to Alternaria tenuissima, confirmed through both sequence identity and phylogenetic analysis. The identification of Alternaria tenuissima as a soybean pathogen provides essential data for the development of effective disease management strategies in Kazakhstan’s soybean production.