Mago R, Bariana H S, Dundas I S, Spielmeyer W, Lawrence G J, Pryor A J, Ellis J G
CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
Theor Appl Genet. 2005 Aug;111(3):496-504. doi: 10.1007/s00122-005-2039-z. Epub 2005 May 26.
The use of major resistance genes is the most cost-effective strategy for preventing stem rust epidemics in Australian wheat crops. The long-term success of this strategy is dependent on combining resistance genes that are effective against all predominant races of the pathogen, a task greatly assisted by the use of molecular markers linked to individual resistance genes. The wheat stem rust resistance genes Sr24 and Sr26 (derived from Agropyron elongatum) and SrR and Sr31 (derived from rye) are available in wheat as segments of alien chromosome translocated to wheat chromosomes. Each of these genes provides resistance to all races of wheat stem rust currently found in Australia . We have developed robust PCR markers for Sr24 and Sr26 (this study) and SrR and Sr31 (previously reported) that are applicable across a wide selection of Australian wheat germplasm. Wheat lines have recently become available in which the size of the alien segments containing Sr26, SrR and Sr31 has been reduced. Newly developed PCR-markers can be used to identify the presence of the shorter alien segment in all cases. Assuming that these genes have different gene-for-gene specificities and that the wheat industry will discourage the use of varieties carrying single genes only, the newly developed PCR markers will facilitate the incorporation of two or more of the genes Sr24, Sr26, SrR and Sr31 into wheat lines and have the potential to provide durable control to stem rust in Australia and elsewhere.
利用主要抗性基因是预防澳大利亚小麦作物秆锈病流行最具成本效益的策略。该策略的长期成功取决于组合对病原体所有主要小种均有效的抗性基因，而与单个抗性基因连锁的分子标记的使用极大地助力了这一任务。小麦秆锈病抗性基因Sr24和Sr26（源自长穗偃麦草）以及SrR和Sr31（源自黑麦）在小麦中以易位到小麦染色体上的外源染色体片段形式存在。这些基因中的每一个都对目前在澳大利亚发现的所有小麦秆锈病小种具有抗性。我们已经为Sr24和Sr26（本研究）以及SrR和Sr31（先前已报道）开发了可靠的PCR标记，这些标记适用于广泛选择的澳大利亚小麦种质。最近已有小麦品系可用，其中含有Sr26、SrR和Sr31的外源片段大小已减小。新开发的PCR标记可用于在所有情况下鉴定较短外源片段的存在。假设这些基因具有不同的基因对基因特异性，并且小麦产业将不鼓励仅使用携带单个基因的品种，那么新开发的PCR标记将有助于将Sr24、Sr26、SrR和Sr31中的两个或更多基因整合到小麦品系中，并有可能为澳大利亚及其他地区的秆锈病提供持久防治。
