Evaluation of some resistance sources of spring barley for yellow rust and powdery mildew diseases

Powdery mildew and yellow rust are two important diseases of barley in Iran that annually cause yield and quality loss to the barley crop. The use of disease-resistant cultivars is known as the most effective, economically sound and environmentally safe method for the control of some important diseases of cereals including rusts and powdery mildew. The objective of this study was to identify sources of genetic resistance in commercial European barley cultivars with the goal of using these genetic sources in our national barley breeding program. A set of 148 commercial European barley cultivars were evaluated for agronomical traits, yellow rust and powdery mildew resistance under the field conditions during two consecutive cropping seasons. In the first cropping season (2011-2012), due to the limitation of available seeds, the experiment was conducted only at the Agricultural Research Station of Torogh (Mashhad). The genotypes were evaluated for agronomical traits and powdery mildew resistance. In the second cropping season (2012-2013) the cultivars were evaluated in Torogh and Araghi Mahale station (Gorgan) against powdery mildew and in Ardabil station against yellow rust. Furthermore, 18 cultivars that showed good field performance and resistance to powdery mildew were selected and compared with Bahman and CB-83-17 (local checks) in a preliminary yield trial in Torogh station in 2012-2013 cropping season. Based on the results of this experiment, 8 cultivars that showed yield superiority over the checks and mostly were powdery mildew and yellow rust resistant were selected and introduced to the breeding program of temperate and cold regions. Our results also indicated that a number of cultivars showed a high level of powdery mildew and yellow rust resistance and could be used in breeding programs as the resistant parent to transfer the resistance gene(s) to the new cultivars.