Crop Development Centre/Department of Plant Science, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada.
Lacombe Research and Development Centre, Agriculture and Agri-Food Canada, Lacombe, AB T4L 1W1, Canada.
Plant Dis. 2018 Sep;102(9):1828-1833. doi: 10.1094/PDIS-12-17-1920-RE. Epub 2018 Jul 11.
A complex of leaf-spotting diseases-tan spot, the Septoria complex, spot blotch, and powdery mildew-are frequently observed on winter wheat in western Canada; however, there are few studies indicating varietal differences in reaction to these diseases or the benefit of fungicide application. To determine the benefit of varietal improvement and multiple fungicide treatments and application timings, field experiments were conducted at six site-years in western Canada. Two cultivars varying in reaction to leaf spot diseases were used in combination with fungicide treatments. Disease severity ranged from trace to 64% of the combined flag and penultimate leaf area diseased, differed between cultivars, and was reduced from the check by some fungicide treatments. Yield improvement by fungicide treatment varied from 3.3 to 13.2% greater than the nontreated check. At two site-years, the split application of two half rates of fungicide resulted in the greatest yield; however, in both cases, the yield benefit did not differ from a single application at the flag leaf growth stage. Cultivar selection and fungicide use under environments conducive to disease are beneficial components of an integrated leaf spot disease management program for winter wheat in western Canada.
在加拿大西部，冬小麦常受到叶斑病复合病——叶斑病、Septoria 复合病、斑点病和白粉病的影响；然而，很少有研究表明品种对这些疾病的反应存在差异，也很少有研究表明杀菌剂的应用是否有益。为了确定品种改良和多种杀菌剂处理以及施药时间的益处，在加拿大西部的 6 个地点进行了田间试验。两个对叶斑病反应不同的品种与杀菌剂处理相结合。病害严重度从痕迹到联合旗叶和倒数第二叶面积的 64%不等，品种间存在差异，一些杀菌剂处理降低了病情。与未处理的对照相比，杀菌剂处理的产量提高了 3.3%至 13.2%。在两个地点，分两次施用两种半剂量的杀菌剂可获得最大的产量；然而，在这两种情况下，与在旗叶生长阶段进行单次施药相比，产量的提高没有差异。在有利于病害发生的环境下进行品种选择和杀菌剂使用，是加拿大西部冬小麦叶斑病综合管理计划的有益组成部分。
