Evaluation of genetic variation and host resistance to wheat stem rust pathogen ( f. sp. ) in bread wheat ( L.) varieties grown in Türkiye.

Wheat stem rust, which is caused by f. sp. (), is a highly destructive disease that affects wheat crops on a global scale. In this study, the reactions of 150 bread wheat varieties were evaluated for natural infection at the adult-plant stage in the 2019-2020 and 2020-2021 growing seasons, and they were analyzed using specific molecular markers to detect stem rust resistance genes (, , , , , , , and ). Based on phenotypic data, the majority of the varieties (62%) were resistant or moderately resistant to natural infection. According to molecular results, it was identified that was present in 103 varieties, in nine varieties, in six varieties, and , , and in one variety each. Additionally, their combinations + , + , + , and + were detected in these varieties. On the other hand, and were not identified. In addition, many varieties had low stem rust scores, including a large minority that lacked . These varieties must have useful resistance to stem rust and could be the basis for selecting greater, possibly durable resistance.