Kielsmeier-Cook Joshua, Danilova Tatiana V, Friebe Bernd, Rouse Matthew N
Department of Plant Pathology, University of Minnesota, St. Paul 55108.
Wheat Genetics Resource Center, Department of Plant Pathology, Kansas State University, Manhattan 66506.
Plant Dis. 2015 Oct;99(10):1317-1325. doi: 10.1094/PDIS-09-14-0922-RE. Epub 2015 Aug 14.
New races of Puccinia graminis f. sp. tritici, the causal agent of stem rust, threaten global wheat production. In particular, races belonging to the Ug99 race group significantly contribute to yield loss in several African nations. Genetic resistance remains the most effective means of controlling this disease. A collection of 546 wheat-intra- and intergeneric hybrids developed by W. J. Sando (United States Department of Agriculture, Beltsville, MD) was screened with eight races of P. graminis f. sp. tritici, including races TTKSK, TTKST, TTTSK, TRTTF, TTTTF, TPMKC, RKQQC, and QTHJC. There were 152 accessions resistant to one or more races and 29 accessions resistant to TTKSK, TTKST, and TTTSK. Of these 29 accessions, 9 were resistant to all races, 14 had infection type patterns that were indistinguishable from cultivars possessing Sr9h and Sr42, 2 were indistinguishable from accessions with SrTmp, and 4 did not display resistant patterns of accessions with any known Sr gene. Three accessions (604981, 605286, and 611932) characterized cytogenetically were disomic substitution lines, each with a single Thinopyrum ponticum chromosome pair. One accession (606057) was a disomic substitution or addition line with two pairs of T. ponticum chromosomes. In total, seven accessions are postulated to contain novel stem rust resistance genes. This research indicates the value of extant collections of wheat-intergeneric hybrids as sources of disease resistance genes.
小麦秆锈病的病原菌——小麦秆锈菌新小种威胁着全球小麦生产。特别是属于Ug99小种组的小种在几个非洲国家造成了严重的产量损失。遗传抗性仍然是控制这种病害最有效的手段。用8个小麦秆锈菌小种对由W. J. 桑多（美国农业部，马里兰州贝尔茨维尔）培育的546个小麦属内和属间杂种进行了筛选，这些小种包括TTKSK、TTKST、TTTSK、TRTTF、TTTTF、TPMKC、RKQQC和QTHJC。有152份材料对一个或多个小种具有抗性，29份材料对TTKSK、TTKST和TTTSK具有抗性。在这29份材料中，9份对所有小种都具有抗性，14份的感染类型模式与携带Sr9h和Sr42的品种无法区分，2份与携带SrTmp的材料无法区分，4份没有显示出具有任何已知Sr基因的材料的抗性模式。通过细胞遗传学鉴定的3份材料（604981、605286和611932）是二体代换系，每个系都有一对单倍体的蓬蒂山羊草染色体。一份材料（606057）是具有两对蓬蒂山羊草染色体的二体代换或附加系。总共推测有7份材料含有新的秆锈病抗性基因。这项研究表明了现存小麦属间杂种收集物作为抗病基因来源的价值。
