Evaluation of resistance of spring durum wheat germplasm from Russia and Kazakhstan to fungal foliar pathogens

Spring durum wheat ( Triticum durum ) is an important crop in Russia and Kazakhstan. There are substantial yield losses due to fungal diseases. The research focused on host plant resistance to fungal diseases, and identification of the sources of multiple resistance which can be deployed in durum wheat breeding programs. Extensive environmental varietal testing experiments at places with diverse meteorological factors allows the selection of valuable material. In 2017 and 2018, a collection of 21 spring durum wheat accessions from the Kazakhstan-Siberian Network for Wheat Improvement (KASIB) was studied under high disease pressure. The following diseases were evaluated in three regions of Russia (Omsk, Altai and Samara), in Southern Kazakhstan and in Kenya: leaf, stem and yellow rusts, powdery mildew, glume blotch, tan spot and spot blotch. As the result, three breeding lines with multiple disease resistance to three rust species, powdery mildew and leaf blotches were identified: Hordeiforme 178-05-02, Hordeiforme 05-42-12 and Hordeiforme 1591-21. Furthermore, the accessions resistant to rusts or spots were also identified. Phytopathological studies and molecular marker analysis showed absence of genes Lr1, Lr3, Lr9, Lr10, Lr19/Sr25, Lr20/Sr15, Lr24/Sr24, Lr26/Sr31/Yr9/Pm8, Lr34/Sr57/Yr18 and Lr37/Sr38/Yr17 . Clustering of durum wheat accessions based on similarity in resistance and susceptibility revealed three main groups; accessions susceptible to all three rusts, those with some resistance to one or two rusts, and those with seedling resistance to leaf rust only.