ارزیابی مزرعه ای مقاومت ارقام گندم به زنگ زرد در استان گلستان

Yellow rust, caused by Puccinia striiformis f. sp. Tritici (PST), is a major wheat disease that poses a global threat to production. The frequency and severity of this disease vary depending on the susceptibility of wheat varieties, climatic conditions, and farming systems. This study was conducted to evaluate the field resistance of wheat cultivars to yellow rust in Golestan Province. Due to the presence of natural infection conditions during the agricultural year 2023-2024, observations were made on disease incidence factors (DI), Final Rust Severity (FRS), and infection type (IT) from the flag leaf stage (Gs47) to the flowering stage (Gs69) for 15 rainfed and irrigated wheat cultivars. These varieties are predominantly cultivated across 11 districts of Golestan Province (Gorgan, Gonbad-e Kavus, Bandar-e Torkman, Gaz, Gomishan, Kordkuy, Aq Qala, Aliabad-e Katul, Azadshahr, Galikash, and Ramian). Within each district, a single field was selected per variety, and within each field, five plots were randomly chosen for data collection. The collected data were recorded in the Plant Protection Organization's comprehensive monitoring system for damaging agents. Then, the coefficient of infection (CI) was calculated for each cultivar. The evaluation results for resistance factors including DI, FRS, and CI indicated that the cultivars Basilico, Collector, Pishgam, and Ehsan, with an infection type of MR, were identified as moderately resistant; the cultivar Tirgan, with an infection type of M, was categorized as intermediate; the cultivars Taktaz, Arman, Kouhdasht, Araz, Karim, Oba, and Kalateh, with an infection type of MS, were recognized as moderately susceptible; and the varieties Aseman, Qabus, and Line 17, with an infection type of S, were classified as susceptible.