Leaf and stem diseases (rusts and blotches) are harmful to spring wheat in all areas of its cultivation. The use of resistant varieties is an environmentally safe way of protection. The objective of the present study was to comprehensively evaluate leaf and stem disease resistance in 44 promising cultivars of soft spring wheat, as well as to identify Lr‑ and Sr‑genes in them. The accessions were obtained from the Kazakhstan‑Siberian Spring Wheat Improvement Network (KASIB) in 2017 and 2018. Wheat resistance to leaf and stem rust, to septoriosis and to tan spot was evaluated in field conditions in Southern Kazakhstan (infection plot at the Research Institute for Biological Safety Problems). Wheat seedlings resistance to septoriosis, leaf and stem rust was evaluated under laboratory conditions. The Lr and Sr genes were identified using a phytopathological test and molecular markers. Field studies resulted in selection of two lines, Lut. KS 14/09‑2 and SPCHS 69, with highly effective group resistance to rusts and blotches. By using molecular markers, the gene cluster Lr34/Sr57/Yr18/Pm38, Lr1 gene, and wheat‑rye translocation 1BL.1RS carrying genes Lr26/Sr31/Yr9/Pm8 were detected in Lut. KS 14/09‑2. A translocation from wheatgrass with highly effective genes of resistance to stem (Sr24) and leaf (Lr24) rusts, as well as 1AL.1RS translocation from rye with a complex of effective genes of resistance to fungous diseases and pests were detected in the line SPCHS 69. Eight wheat lines (Lut. 393/05, Lut. 2028, Lut. 261, Lut. 1103, Lut. 22‑17, Lut. 37‑17, line 4‑10‑16, Stepnaya 245) appeared to be resistant to Stagonospora nodorum blotch and tan spot; and four varieties (OmGAU‑100, Element 22, Stolypinskaya 2, and Silach) demonstrated resistance to leaf and stem rust. The molecular marker analysis showed moderate genetic diversity of the studied collection in terms of resistance genes. The genes Lr1, Lr9, Lr10, Lr19/Sr25, Lr24/Sr24, Lr26/Sr31/Yr9/Pm8, Lr34/Sr57/Yr18/Pm38, Lr37/Sr38/Yr17, both separately and in different combinations, were detected in the tested accessions. The evaluated material may be recommended for the use in wheat breeding for disease resistance in Russia and in Kazakhstan.
Chracteristic of perspective common spring wheat accessions for resistance to foliar diseases
