Resistance of spring bread wheat cultivars and lines to Septoria leaf blotch, tan spot, and spot blotch pathogens

Abstract

Background. Leaf and stem diseases of cereal crops are among the most harmful in the agrocenoses of Tambov Province, significantly reducing grain yield and rapidly progressing in many regions of Russia. The aim of the study was to identify spring bread wheat lines and cultivars developed at the Middle-Russian Branch of the I.V. Michurin Federal Science Center that show resistance to leaf and stem diseases.Materials and methods. The target material was represented by 3 cultivars and 23 breeding lines of spring bread wheat. Disease resistance in seedlings was assessed in the laboratory, while for adult plants the process was carried out in the field in 2020–2022. The presence of the Tsn1 allele controlling susceptibility to the PtrToxA fungal toxin was detected using the Xfcp623 molecular marker.Results and conclusions. Accessions with high levels of resistance to Zymoseptoria tritici were identified: L-8252, L-82/60, L-8107, L-8078(23), L-43-9, L-43-1, L-4, Stb-8/15, Stb-7/15, and Stb-92. Accessions Stb-97, Stb-89, Stb-89(a), Stb-90, Stb-34, and Rl-6-22 were resistant to Parastagonospora nodorum; L-8134, L-8114, L-82/60, L-8107, Stb-10/15, Stb-9/15, Stb-8/15, Stb-7/15, Stb-97, Stb-89, Stb-89(a), Stb-90, Stb-34, and Rl-6-22 to P. pseudonodorum; L-8252, L-8107, L-43-9, L-43-1, L-4, Stb10/15, Stb-9/15, Stb-97, Stb-92, Stb-92(a), Stb-89, Stb-89(a), and Stb-34 to Pyrenophora tritici-repentis; and L-8114, L-82/60, L-43-9, L-43-1, L-4, Stb-90, Stb-34, and Rl-6-22 to Bipolaris sorokiniana. The cultivars and breeding lines showed group resistance to two, three or four pathogens. It was Lines L-8252, L-8134, L-82/60, L-8107, L-8078 (23), L-43-9, L-43-1, L-4, Stb-89, Stb-90, Stb-34, and L-33809-7-3 were observed to carry the recessive allele of the tsn1 gene.