Kolmer J A
United States Department of Agriculture-Agricultural Research Service, Cereal Disease Laboratory, St. Paul, MN 55108.
Plant Dis. 2010 May;94(5):628-632. doi: 10.1094/PDIS-94-5-0628.
Leaf rust, caused by the fungus Puccinia triticina, is an important disease of soft red winter wheat cultivars that are grown in the southern and eastern United States. The objectives of this study were to identify the leaf rust resistance genes in two soft red winter wheat cultivars, Coker 9663 and Pioneer 26R61, that have been widely grown and were initially highly resistant to leaf rust. Both cultivars were crossed with the leaf-rust-susceptible spring wheat cv. Thatcher and the F plants were crossed to Thatcher to obtain backcross (BC) F families. In seedlings, the Thatcher/Coker 9663 BCF families segregated for three independent seedling resistance genes when tested with different leaf rust isolates. The leaf rust infection types of selected BCF lines, when tested with different leaf rust isolates, indicated that seedling resistance genes Lr9, Lr10, and Lr14a were present. In field plot tests, BCF lines that were seedling susceptible had some adult plant resistance to leaf rust. Seedlings of the Thatcher/Pioneer 26R61 BCF families segregated for two independent resistance genes. Infection types of selected BCF lines indicated the presence of Lr14b and Lr26. The adult plant gene Lr13 was determined to be present in selected BCF lines that were tested with different leaf rust isolates in greenhouse tests.
叶锈病由真菌小麦柄锈菌引起，是美国南部和东部种植的软红冬小麦品种的一种重要病害。本研究的目的是鉴定两个软红冬小麦品种Coker 9663和先锋26R61中的叶锈病抗性基因，这两个品种已广泛种植且最初对叶锈病具有高度抗性。将这两个品种与感叶锈病的春小麦品种撒切尔杂交，并将F植株与撒切尔杂交以获得回交（BC）F家系。在幼苗中，用不同的叶锈病菌株进行测试时，撒切尔/Coker 9663 BCF家系分离出三个独立的幼苗抗性基因。用不同的叶锈病菌株进行测试时，所选BCF系的叶锈病感染类型表明存在幼苗抗性基因Lr9、Lr10和Lr14a。在田间小区试验中，幼苗感病的BCF系对叶锈病具有一些成株抗性。撒切尔/先锋26R61 BCF家系的幼苗分离出两个独立的抗性基因。所选BCF系的感染类型表明存在Lr14b和Lr26。在温室试验中，用不同的叶锈病菌株进行测试时，确定所选BCF系中存在成株基因Lr13。
