Department of Plant Science and Plant Pathology, Montana State University, Bozeman.
Phytopathology. 2010 Jan;100(1):49-57. doi: 10.1094/PHYTO-100-1-0049.
Caused by a complex of Fusarium species including F. culmorum, F. graminearum, and F. pseudograminearum, Fusarium crown rot (FCR) is an important cereal disease worldwide. For this study, Fusarium population dynamics were examined in spring wheat residues sampled from dryland field locations near Bozeman and Huntley, MT, using a quantitative real-time polymerase chain reaction (qPCR) Taqman assay that detects F. culmorum, F. graminearum, and F. pseudograminearum. Between August 2005 and June 2007, Fusarium populations and residue decomposition were measured eight times for standing stubble (0 to 20 cm above the soil surface), lower stem (20 to 38 cm), middle stem (38 to 66 cm), and chaff residues. Large Fusarium populations were found in stubble collected in August 2005 from F. pseudograminearum-inoculated plots. These populations declined rapidly over the next 8 months. Remnant Fusarium populations in inoculated stubble were stable relative to residue biomass from April 2006 until June 2007. These two phases of population dynamics were observed at both locations. Relative to inoculated stubble populations, Fusarium populations in other residue fractions and from noninoculated plots were small. In no case were FCR species observed aggressively colonizing noninfested residues based on qPCR data. These results suggest that Fusarium populations are unstable in the first few months after harvest and do not expand into noninfested wheat residues. Fusarium populations remaining after 8 months were stable for at least another 14 months in standing stubble providing significant inoculums for newly sown crops.
由包括尖孢镰刀菌（Fusarium culmorum）、禾谷镰刀菌（Fusarium graminearum）和禾谷镰刀菌（Fusarium pseudograminearum）在内的镰刀菌物种引起的镰刀菌顶腐病（FCR）是一种世界性的重要谷类病害。在这项研究中，使用定量实时聚合酶链反应（qPCR）Taqman 检测法检测到的尖孢镰刀菌、禾谷镰刀菌和禾谷镰刀菌，检测了来自蒙大拿州博兹曼和亨特利附近旱地田间地点的春小麦残茬中镰刀菌种群的动态。2005 年 8 月至 2007 年 6 月，对 0 至 20 厘米（距土壤表面）、下部茎（20 至 38 厘米）、中部茎（38 至 66 厘米）和麦糠残茬的立茬、下茎和中茎进行了 8 次测定。2005 年 8 月从接种尖孢镰刀菌的地块中采集的麦茬中发现了大量镰刀菌。这些种群在接下来的 8 个月里迅速下降。2006 年 4 月至 2007 年 6 月，接种麦茬中的残留镰刀菌种群相对残茬生物量保持稳定。在这两个地点都观察到了这两个阶段的种群动态。与接种麦茬的种群相比，其他残茬部分和未接种地块的镰刀菌种群较小。根据 qPCR 数据，从未发现 FCR 物种积极定植于未受侵染的残茬。这些结果表明，镰刀菌种群在收获后的头几个月不稳定，不会扩展到未受侵染的小麦残茬中。在立茬中，收获 8 个月后仍保持稳定的镰刀菌种群在至少另外 14 个月内保持稳定，为新播种的作物提供了大量接种体。
