COMPONENTS OF RESISTANCE TO SEPTORIA-TRITICI BLOTCH IN 4 MOROCCAN BREAD WHEAT GENOTYPES

Four bread wheat genotypes from Morocco were evaluated for components of resistance to septoria tritici blotch (STB). Genotype BT93 was the most resistant genotype and had fewer lesions per gm dry weight of fol iage, lower receptivity (final number of visible lesions per square ce ntimeter of leaf tissue), reduced necrotic leaf area (as measured by r elative water content and total chlorophyll content), and a longer inc ubation period than the other three genotypes. Thus, BT93 represents a potential source of STB resistance to wheat breeding programs.