HighlightsWe review the genetics of wheat resistance to Septoria tritici blotch, with a map of known genes.Qualitative resistance is usually monogenic, genotype-specific and non-durable.Quantitative resistance is generally polygenic with low specificity and greater durability.Major requirements for resistance breeding are diverse germplasm and field sites with severe Septoria.

Twenty-four wheat cultivars and breeding lines were screened for isolate-specific resistance to septoria tritici blotch (STB) caused by 12 isolates of Mycosphaerella graminicola. New isolate-specific resistances that could be used in wheat breeding were identified. Major sources of resistance to STB used in world breeding programmes for decades, such as Kavkaz-K4500, Veranopolis, Catbird and TE9111, have several isolate-specific resistances. This suggests that 'pyramiding' several resistance genes in one cultivar may be an effective and durable strategy for breeding for resistance to STB in wheat. Several cultivars, including Arina, Milan and Senat, had high levels of partial resistance to most isolates tested as well as isolatespecific resistances. Resistance to isolate IPO323 was common, present in all but one of the major sources of resistance tested. This suggests that resistance to IPO323 may be an indicator of varietal resistance to STB in the field.