Disease responses of Barley genotypes with Puccinia hordei in Iraq
Authors: Mohammed M. Salih and Mohammed A. AL- Hamdany
Citation: Pakistan J. Phytopathology, 24(1):74-78, 2012
Disease severity of Puccinia hordei Otth (Uredia/cm of flag leaf, Uredia/flag leaf and Uredia/ tiller) and latent period (LD50) were thoroughly investigated under green house and field conditions respectively in Baghdad region. Barley genotypes (9 cultivars, 13 induced mutants, 8 selectives, and 300 M2 selected variants following gamma irradiation on Numar cultivar) were used. Data of pustule density on these genotypes under artificially heavy epidemic form indicated that disease responses of all tested genotypes could be classified to four groups: highly susceptible such as cultivars Golden melon, Aimer, Beacher, Weah and Arivat, mutants: D/21 , D/30 and D/32; 2: Susceptible including Cultivar Prior, the mutants D/24,C/50,NA/20 and C/63, the selectives 480,552, and 557; Moderate susceptible included cultivar Gazera 2 , the mutants D/34, TB/5 and VB/7, the selectives 102,576,577, and 657 and mildew resistance source H-421; finally Moderate resistance included cultivars Gazera 1 and Numar, the mutants OA/15, VB/6, and SA/12, all M2 Numar variants regardless used doses of gamma ray. The latent period of P. hordei on detached leaf was 132 hrs. in the first two groups, 156 hrs. in the third and 168 hrs. on barley genotypes might have moderate resistant reactions.
Key Words: Barley, Leaf rust, Puccinia hordei, Pustule density, Latent period