Jin Y, Singh R P, Ward R W, Wanyera R, Kinyua M, Njau P, Fetch T, Pretorius Z A, Yahyaoui A
United States Department of Agriculture-Agricultural Research Service, (USDA-ARS) Cereal Disease Laboratory, University of Minnesota, St. Paul.
International Maize and Wheat Improvement Center (CIMMYT), Apdo, Postal 6-641, Mexico D.F., Mexico.
Plant Dis. 2007 Sep;91(9):1096-1099. doi: 10.1094/PDIS-91-9-1096.
Stem rust, caused by Puccinia graminis f. sp. tritici, historically was one of the most destructive diseases of wheat and barley. The disease has been under effective control worldwide through the widespread use of host resistance. A number of stem rust resistance genes in wheat have been characterized for their reactions to specific races of P. graminis f. sp. tritici. Adult plant responses to race TTKS (also known as Ug99) of monogenic lines for Sr genes, a direct measurement of the effectiveness for a given gene, have not been investigated to any extent. This report summarizes adult plant infection responses and seedling infection types for monogenic lines of designated Sr genes challenged with race TTKS. High infection types at the seedling stage and susceptible infection responses in adult plants were observed on monogenic lines carrying Sr5, 6, 7a, 7b, 8a, 8b, 9a, 9b, 9d, 9g, 10, 11, 12, 15, 16, 17, 18, 19, 20, 23, 30, 31, 34, 38, and Wld-1. Monogenic lines of resistance genes Sr13, 22, 24, 25, 26, 27, 28, 32, 33, 35, 36, 37, 39, 40, 44, Tmp, and Tt-3 were effective against TTKS both at the seedling and adult plant stages. The low infection types to race TTKS observed for these resistance genes corresponded to the expected low infections of these genes to other incompatible races of P. graminis f. sp. tritici. The level of resistance conferred by these genes at the adult plant stage varied between highly resistant to moderately susceptible. The results from this study were inconclusive for determining the effectiveness of resistance genes Sr9e, 14, 21, and 29 against race TTKS. The understanding of the effectiveness of individual Sr genes against race TTKS will facilitate the utilization of these genes in breeding for stem rust resistance in wheat.
秆锈病由小麦秆锈菌引起，在历史上是小麦和大麦最具破坏性的病害之一。通过广泛使用寄主抗性，该病在全球范围内得到了有效控制。许多小麦中的秆锈病抗性基因已针对其对小麦秆锈菌特定小种的反应进行了表征。单基因系的成年植株对秆锈菌小种TTKS（也称为Ug99）的反应，作为给定基因有效性的直接衡量标准，尚未进行任何程度的研究。本报告总结了用小种TTKS挑战的指定Sr基因单基因系的成年植株感染反应和幼苗感染类型。在携带Sr5、6、7a、7b、8a、8b、9a、9b、9d、9g、10、11、12、15、16、17、18、19、20、23、30、31、34、38和Wld-1的单基因系上，观察到幼苗期的高感染类型和成年植株中的感病感染反应。抗性基因Sr13、22、24、25、26、27、28、32、33、35、36、37、39、40、44、Tmp和Tt-3的单基因系在幼苗期和成年植株期均对TTKS有效。这些抗性基因对小种TTKS观察到的低感染类型与这些基因对小麦秆锈菌其他不亲和小种的预期低感染相对应。这些基因在成年植株期赋予的抗性水平在高抗到中感之间有所不同。本研究结果对于确定抗性基因Sr9e、14、21和29对小种TTKS的有效性尚无定论。了解单个Sr基因对小种TTKS的有效性将有助于在小麦秆锈病抗性育种中利用这些基因。
