Biennial Workshop on the Smut Fungi

Abstract

Abstract:In 1993-2005, resistance to powdery mildew was studied in 168 foreign varieties of spring barley included in Czech Official Trials in that period. Sixteen known resistances to powdery mildew were identified (Ab, Al, Ar, HH, Kw, La, Ly, MC, Mlo, N81, Ri, Ru, Sp, St, Tu, and We). Unknown resistances were found in 32 varieties, in nine of which these resistances were effective against all used pathotypes of the pathogen. Seven varieties (= 5%) exhibited heterogeneity in the examined trait, i.e. they are composed of lines (usually of two) with different resistances to powder mildew. The resistance Mlo, which was found in 75 homogeneous varieties (= 46%), dominated in the set. The resistances Ru, We, Ar and La were frequently present. The examined set includes 53% of varieties resistant to all used indigenous pathotypes of the pathogen.