Stripe rust (Puccinia striiformis f. sp. tritici) is one of the most destructive diseases of wheat and can cause substantial yield losses. Genetic resistance remains the most effective strategy for disease control; however, the frequent emergence of new pathogen races necessitates the identification of novel and effective resistance sources. Wheat landraces, owing to their long-term adaptation to diverse climatic and soil conditions, often harbor valuable resistance traits and can broaden the narrow genetic base of elite cultivars. In the present study, 230 bread wheat accessions of foreign origin from the Iranian National Plant Gene Bank were evaluated to identify new genetic sources of resistance to stripe rust. During the first year, the accessions were assessed under field conditions at the stripe rust nursery in Karaj based on infection type (IT), disease severity (DS), and coefficient of infection (CI). The results indicated that 43.5% of the evaluated accessions exhibited resistant or moderately resistant responses. Accessions showing superior resistance were further evaluated in the second year under similar field conditions and subsequently at the seedling stage under controlled greenhouse conditions using different pathogen pathotypes. Principal component analysis (PCA) was employed to classify the genotypes based on their resistance responses to the pathotypes, revealing that the first two principal components accounted for 92.2% of the total variation. Cluster analysis grouped the genotypes into four distinct clusters with different resistance characteristics, and seven distinct resistance response patterns against the pathotypes were identified. Based on the virulence profiles of the pathotypes, the presence of one or a combination of resistance genes Yr1, Yr4, Yr5, Yr10, Yr15, Yr24, YrSP, and YrSU was postulated in genotypes KC8592, KC8694, KC8893, KC8894, KC8899, and KC8900, while the presence of Yr8 and Yr27 was likely in genotypes KC8593.2 and KC8685. Moreover, several genotypes, including KC8686, KC8690, and KC8698, were identified as potential sources of adult plant resistance. Overall, the results revealed substantial genetic diversity for stripe rust resistance, and the identified resistant genotypes represent valuable resources for wheat breeding programs aimed at enhancing stripe rust resistance.
Type of Study:
Applicable |
Subject:
Subject 01 Received: 2025/05/5 | Accepted: 2026/02/1 | Published: 2026/02/3