Evaluation of stem rust tolerance in wheat

The development of stem rust epidemic was studied in a test over two years by the modified Center-pivot method in 17 winter wheat genotypes of differi ng resistance. The spreading of epidemic depended on the level of the disease measured in cultivars just at the spreader plot. This was stable in the years of observ ation, only the severity of the disease differed in the two years. Tolerance could be identified at various levels of susceptibility and resis tance. Tolerance is a useful trait, being independent from resistance, but can nor replace the race specific or other types of resistance. A direct selection for tolerance is not easy, but the selection for not shr ivelling grains may result also in tolerant genotypes. Identification of to lerance needs tests over several years.