QUANTITATIVE RESISTANCE TO BARLEY LEAF STRIPE (PYRENOPHORA-GRAMINEA) IS DOMINATED BY ONE MAJOR LOCUS

A major gene underlying quantitative resistance of barley against Pyre nophora graminea, a seed-borne pathogen causing leaf stripe, was mappe d with molecular markers in a barley doubled haploid (DH) population d erived from the cross 'Proctor' x 'Nudinka'. This quantitative trait l ocus (QTL) accounts for r(2) = 58.5% and was mapped on barley chromoso me 1, tightly linked to the ''naked'' gene. A second resistance QTL ac counting for 29.3% of the variation in the trait was identified on the P arm of barley chromosome 2. Another two minor QTLs were detected by further analysis. None of the QTLs was found in the barley chromosome 2 ''Vada'' region studied by Giese et al. (1993).