Uddin W, Soika M D, McNitt A S, Fidanza M
Department of Plant Pathology.
Department of Crop and Soil Sciences, The Pennsylvania State University, University Park 16802.
Plant Dis. 2004 Oct;88(10):1146-1152. doi: 10.1094/PDIS.2004.88.10.1146.
Ethofumesate is a widely used herbicide for control of annual bluegrass (Poa annua) in perennial ryegrass (Lolium perenne) fairways on golf courses in the United States. Effect of timing of ethofumesate application on development of gray leaf spot was evaluated on perennial ryegrass turf treated with six classes of fungicide. Two applications of ethofumesate (2.28 kg a.i./ha) were made to perennial ryegrass turf maintained at a 2-cm height, at 4-week intervals, each fall (October and November 1999 and 2000) or spring (April and May 2000 and 2001). In addition, turf was treated with the fungicides, azoxystrobin, chlorothalonil, flutolanil, iprodione, propiconazole, or thiophanate-methyl at the label rates at 14-day intervals. There were significant effects (P ≤ 0.05) of ethofumesate application timing and fungicide regime on gray leaf spot development. There also were significant interactions between the ethofumesate application timing and fungicide. Severity of gray leaf spot was significantly greater in turf plots treated with ethofumesate in spring compared to turf treated in fall or nontreated control plots treated with fungicides, flutolanil, iprodione, and propiconazole that were relatively less effective in control of gray leaf spot. There was no significant difference in disease severity in turf treated with ethofumesate in fall or to turf not treated with herbicide regardless of the fungicide used. Results of this study indicate that spring application of ethofumesate contributes to development of gray leaf spot epidemics, and the application timing interacts with the classes of fungicides. This study suggests that ethofumesate should be applied only in fall for control of P. annua, particularly in golf courses with a chronic gray leaf spot problem, as part of an integrated management of gray leaf spot in perennial ryegrass fairways.
乙氧呋草黄是一种在美国高尔夫球场多年生黑麦草球道上广泛用于防除一年生早熟禾的除草剂。在使用六类杀菌剂处理的多年生黑麦草草坪上，评估了乙氧呋草黄施用时间对灰斑病发生发展的影响。在1999年和2000年的每个秋季（10月和11月）或2000年和2001年的春季（4月和5月），以2厘米的高度对多年生黑麦草草坪进行两次乙氧呋草黄（2.28千克有效成分/公顷）施用，间隔4周。此外，草坪每隔14天以标签推荐剂量用杀菌剂嘧菌酯、百菌清、氟纹胺、异菌脲、丙环唑或甲基硫菌灵进行处理。乙氧呋草黄施用时间和杀菌剂处理方式对灰斑病的发生发展有显著影响（P≤０.０５）。乙氧呋草黄施用时间和杀菌剂之间也存在显著的交互作用。与秋季施用乙氧呋草黄的草坪地块或用相对不太能有效防治灰斑病的杀菌剂氟纹胺、异菌脲和丙环唑处理的未处理对照地块相比，春季施用乙氧呋草黄的草坪地块上灰斑病的严重程度显著更高。秋季施用乙氧呋草黄的草坪与未用除草剂处理的草坪相比，无论使用何种杀菌剂，病害严重程度均无显著差异。本研究结果表明，春季施用乙氧呋草黄会促使灰斑病流行，且施用时间与杀菌剂种类存在交互作用。本研究表明，乙氧呋草黄应仅在秋季用于防除一年生早熟禾，特别是在有慢性灰斑病问题的高尔夫球场，作为多年生黑麦草球道灰斑病综合管理的一部分。
