Rahmatov Mahbubjon, Rouse Matthew N, Steffenson Brian J, Andersson Staffan C, Wanyera Ruth, Pretorius Zacharias A, Houben Andreas, Kumarse Nazari, Bhavani Sridhar, Johansson Eva
Department of Plant Breeding, Swedish University of Agricultural Sciences, SE-23053 Alnarp, Sweden; Department of Plant Pathology, University of Minnesota, St. Paul 55108; and Tajik Agrarian University, Dushanbe, 734017, Tajikistan.
United States Department of Agriculture-Agricultural Research Service, Cereal Disease Laboratory, St. Paul, MN 55108; and Department of Plant Pathology, University of Minnesota.
Plant Dis. 2016 Jun;100(6):1101-1109. doi: 10.1094/PDIS-12-15-1448-RE. Epub 2016 Mar 23.
Stem rust is one of the most devastating diseases of wheat. Widely virulent races of the pathogen in the Ug99 lineage (e.g., TTKSK) are threatening wheat production worldwide; therefore, there is an urgent need to enhance the diversity of resistance genes in the crop. The objectives of this study were to identify new sources of resistance in wheat-alien introgression derivatives from Secale cereale, Leymus mollis, L. racemosus, and Thinopyrum junceiforme, postulate genes conferring the resistance, and verify the postulated genes by use of molecular markers. From seedling tests conducted in the greenhouse, the presence of seven known stem rust resistance genes (Sr7b, Sr8a, Sr9d, Sr10, Sr31, Sr36, and SrSatu) was postulated in the wheat-alien introgression lines. More lines possessed a high level of resistance in the field compared with the number of lines that were resistant at the seedling stage. Three 2R (2D) wheat-rye substitution lines (SLU210, SLU238, and SLU239) seemed likely to possess new genes for resistance to stem rust based on their resistance pattern to 13 different stem rust races but the genes responsible could not be identified. Wheat-rye, wheat-L. racemosus, and wheat-L. mollis substitutions or translocations with single and multiple interchanges of chromosomes, in particular of the B and D chromosomes of wheat, were verified by a combination of genomic in situ hybridization and molecular markers. Thus, the present study identified novel resistance genes originating from different alien introgressions into the wheat genome of the evaluated lines. Such genes may prove useful in enhancing the diversity of stem rust resistance in wheat against widely virulent pathogen races such as those in the Ug99 lineage.
秆锈病是小麦最具毁灭性的病害之一。Ug99谱系（如TTKSK）中具有广泛毒性的病原菌小种正在威胁全球小麦生产；因此，迫切需要增加该作物中抗性基因的多样性。本研究的目的是在源自黑麦、滨麦、总状披碱草和新麦草的小麦-外源渗入衍生物中鉴定新的抗性来源，推测赋予抗性的基因，并使用分子标记验证推测的基因。通过温室进行的幼苗试验，推测在小麦-外源渗入系中存在7个已知的秆锈病抗性基因（Sr7b、Sr8a、Sr9d、Sr10、Sr31、Sr36和SrSatu）。与在幼苗期具有抗性的品系数量相比，更多的品系在田间具有高水平的抗性。三个2R（2D）小麦-黑麦代换系（SLU210、SLU238和SLU239）基于它们对13个不同秆锈病小种的抗性模式似乎可能拥有新的抗秆锈病基因，但负责的基因无法鉴定。通过基因组原位杂交和分子标记相结合的方法，验证了小麦-黑麦、小麦-总状披碱草和小麦-滨麦的代换系或易位系，其中涉及小麦染色体尤其是B和D染色体的单条和多条染色体的互换。因此，本研究鉴定了源自不同外源渗入到所评估品系小麦基因组中的新抗性基因。这些基因可能有助于增加小麦对诸如Ug99谱系中那些具有广泛毒性的病原菌小种的秆锈病抗性多样性。
