مهدی زهراوی - Department of Genetics and National Plant Gene Bank of Iran, Seed and Plant Improvement Institute, Agricultural Research, Education and Extension Organization (AREEO), P. O. Box: ۳۱۳۵۹-۳۳۱۵۱, Karaj, Iran.
محمد علی دهقان - Agriculture and Natural Resources Research Center of Golestan, Agricultural Research, Education and Extension Organization (AREEO), Iran.

The barley leaf rust has been important in recent years in Iran. In order to identify the genetic resources of resistance to this disease, ۲۰۷ Iranian barley landraces were studied. The germplasms were investigated at the field of Iraqi-Mahalleh research station in Gorgan as the disease hotspot under natural incidence over three years. The results showed that four genotypes including KC۱۸۶۳۸ and KC۱۸۶۴۳ from Golestan and KC۱۹۰۸۷ and KC ۱۹۰۹۳ from Gilan expressed immunity response in all three years of the experiment and ۳۱ accessions were immune in two years. The results of principal component analysis in three years showed that ۹۰.۶۹% of the variations in the data were justified by the first three principal components. The results of this study indicated the possibility of racial variation in the studied disease hotspot. These findings show the importance of tracing the changes in the disease hotspot which is necessary for planning, breeding and cultivation of cultivars with effective resistance. Also, the resistant genotypes identified in this research can be used as genetic resources of leaf rust resistance in breeding programs.

Barley brown rust, Diversity, Landrace, Resistance components