Fig. 1. Segregation of specific resistance to an Australian isolate of M. graminicola in the DH progeny developed from a cross between Veranopolis (containing the Stb2 gene for resistance) and the susceptible parent RAC875-2. Histograms showing frequency distribution of (A) percent leaf area covered with lesions of Septoria tritici blotch and (B) pycnidial density among 106 DH lines. Susceptible classes are indicated with horizontal lines. Phenotypic values of the parents are shown by arrows.