• The Plant Pathology Journal
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• v.27 no.2
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• pp.116-119
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• 2011

Pyrenophora graminea, the causal agent of leaf stripe disease, is an economically important pathogen of barley found worldwide. Forty-four isolates of diverse geographical origin within Syria were grouped into vegetative compatibility groups (VCGs) by demonstrating heterokaryosis by complementation tests using nitrate nonutilizing (nit) mutants. All isolates were grouped into three VCGs-1-A, 1-B and 1-C. No self-incompatibility was observed in any of the isolates tested. VCG 1-A was the most common group within growing regions in Syria and proved to be the most virulent of the VCGs identified. These data indicate that the level of virulence in P. graminea is related to VCG.

• The Korean Journal of Mycology
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• v.8 no.2
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• pp.89-94
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• 1980

Effects of seed disinfectants on loose smut (Ustilago nuda) and leaf stripe (Pyrenophora graminea) of barley were investigated in field tests. For these experiments, seed samples carrying natural infection of Ustilago nuda and Pyrenophora graminea were used and the following fungicides were used: Baytan, Baytan U, Benlate T, Busan 30, KAC-7703, P 242, Panoctine, Sisthane Ec, Sisthane Wp, Sisthane Ds, Sodium Omadine, Terracoat Zn, Vitathiram and Zinc Omadine, respectively. Results have shown that Sisthane and Benlate T have equal effect to Vitathiram against Ustil­ago nuda and Pyrenophora graminea. Baytan U was effective against loose smut but inferior to leaf stripe of barley. P 242 was effective against leaf stripe but inferior to loose smut of barley. Busan 30 have shown moderately inferior effect to Vitathiram against loose smut and leaf stripe of barley. A mild inhibition of seed germination and seedling growth of barley, naked barley and wheat seeds was observed when high concentration of Sisthane and Baytan U were treated in seedling box placed in green house conditions, but no symptom observed in field conditions.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.290-294
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• 2012

The fungus Pyrenophora graminea is the causal agent of barley leaf stripe disease. Two leaf stripe isolates PgSy3 (exhibiting high virulence on the barley cultivar 'Arabi Abiad') and PgSy1 (exhibiting low virulence on Arabi Abiad), were mated and 63 progeny were isolated and phenotyped for the reaction on Arabi Abiad. The population segregated in a 1:1 ratio, 32 virulent to 31 avirulent (${\chi}^2$ = 0.05, P = 0.36), indicating single gene control of PgSy3 virulence on Arabi Abiad. Among 96 AFLP markers identified, three AFLP markers, E37M50-400, E35M59-100 and E38M47-800 were linked to the virulence locus VHv1 in isolate PgSy3. The results of this study indicate that (the three markers) are closely linked to VHv1 and are unique to isolates carrying the virulence locus. This work represents an initial step towards map-based cloning of VHv1 in P. graminea.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.212-215
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• 2012

Pyrenophora graminea, the causal agent of leaf stripe disease, is an economically important pathogen of barley found worldwide. It is critical to clearly define and standardize the leaf stripe assessment methods to avoid subjectivity and variability between assessors. Therefore, in this study, a comparison between the proportion of diseased plants (DP) and the proportion of diseased leaves (DL) per plant was investigated. Disease assessments were made visually at multiple sample sites in artificially and naturally inoculated research and production fields during four growing seasons. There were significant differences (P = 0.001) among cultivars in mean DP and DL averages, which are consistently higher in susceptible barley. However, DP values increased linearly as DL increased. The slopes and intercepts of the DP-DL relationship were consistent over the four growing seasons. This result might make a significant contribution for leaf stripe assessment in barley breeding programme.