Troch V, Audenaert K, Vanheule A, Bekaert B, Höfte M, Haesaert G
Faculty of Applied Bioscience Engineering, University College Ghent (Ghent University Association), and Department of Crop Protection, Laboratory of Phytopathology, Ghent University.
Faculty of Applied Bioscience Engineering, University College Ghent (Ghent University Association).
Plant Dis. 2013 Mar;97(3):410-417. doi: 10.1094/PDIS-02-12-0161-RE.
Triticale (×Triticosecale) is the intergeneric hybrid between the female parent wheat and the male parent rye. With the expansion of the triticale growing area, powdery mildew emerged on this new host and has become a significant disease on triticale. Recent research demonstrated that this "new" powdery mildew on triticale has emerged through a host range expansion of powdery mildew of wheat. Moreover, this expansion occurred recently and multiple times at different locations in Europe. An effective and environmentally sensitive approach to controlling powdery mildew involves breeding crop plants for resistance. The main goal of this study was to identify the presence of powdery mildew resistance in commercial triticale cultivars. First, the avirulence (AVR) genes and gene complexity carried by this new powdery mildew population on triticale were characterized. Virulence was identified for all the resistance genes evaluated in the present study, and virulence frequencies higher than 50% were recorded on the genes Pm3f, Pm5b, Pm6, Pm7, Pm8, and Pm17. Using molecular markers, the presence of resistance genes Pm3f and Pm17 was identified in certain triticale cultivars. The triticale cultivars were also evaluated for the presence of quantitative resistance at adult plant growth stages in a 2-year field experiment. Despite the high disease pressure, cultivars highly resistant at the adult-plant growth stages were identified. Because 'Grenado' also showed effective race-specific resistance, this cultivar could be of high value for breeding for durable resistance to powdery mildew. Altogether, this study reveals valuable information on the presence of powdery mildew resistance in commercial triticale cultivars, which can be used in breeding programs in triticale. Additionally, this study underscores the need to broaden the base of powdery mildew resistance in triticale through introgression and deployment of new sources of mildew resistance, including quantitative resistance.
小黑麦（×Triticosecale）是母本小麦和父本黑麦的属间杂交种。随着小黑麦种植面积的扩大，这种新寄主上出现了白粉病，并已成为小黑麦的一种重要病害。最近的研究表明，小黑麦上这种“新”白粉病是通过小麦白粉病寄主范围的扩大而出现的。此外，这种扩大是最近在欧洲不同地点多次发生的。一种有效且对环境敏感的控制白粉病的方法是培育抗病作物品种。本研究的主要目标是确定商业小黑麦品种中白粉病抗性的存在情况。首先，对小黑麦上这种新白粉病群体携带的无毒（AVR）基因和基因复杂性进行了表征。在本研究中评估的所有抗性基因中都鉴定出了毒性，并且在Pm3f、Pm5b、Pm6、Pm7、Pm8和Pm17基因上记录到毒性频率高于50%。利用分子标记，在某些小黑麦品种中鉴定出了抗性基因Pm3f和Pm17的存在。在一项为期两年的田间试验中，还评估了小黑麦品种在成株生长阶段的数量抗性情况。尽管病害压力很大，但仍鉴定出了在成株生长阶段高度抗病的品种。由于“Grenado”也表现出有效的小种特异性抗性，该品种对于培育对白粉病的持久抗性可能具有很高的价值。总之，本研究揭示了商业小黑麦品种中白粉病抗性存在的有价值信息，可用于小黑麦的育种计划。此外，本研究强调了通过渗入和部署新的抗白粉病来源，包括数量抗性，来拓宽小黑麦抗白粉病基础的必要性。
