Characterization of Tan Spot Races in Kazakhstan

Tan spot disease, which is caused by Pyrenophora tritici-repentis (Ptr), one of the most significant wheat diseases in Kazakhstan, an important wheat-growing region Central Asia. In this study, we aimed to investigate race composition Ptr responsible for tan Kazakhstan through phenotypic and genotypic characterization. During 2019–2020, samples isolates were collected analysis six regions Republic from commercial experimental fields bread durum affected disease. Race classification was based on inoculation bioassay 167 four corresponding differential genotypes, with a PCR assay used identify effector genes. The characterization these showed they belonged different known races (Races 1–4) addition potential atypical that does not fit into current system. We identified two races, Races 1 2, as critical production occur throughout study area. Most exhibited amplification ToxA gene, necrosis-causing effector, consistent results; only 3 4 did show gene. Inoculating sixteen resulted similar 8, according set. However, genetic characterization, possess associated gene expected 8 assignment; therefore, designated them race. According our results, should be both analyses, where possible, adequately capture breadth physiological variation among isolates, possible expansion