Wunsch Michael J, Baker Alexandra H, Kalb David W, Bergstrom Gary C
Department of Plant Pathology and Plant-Microbe Biology, Cornell University, 334 Plant Science, Ithaca, NY 14853 USA.
Plant Dis. 2009 Jan;93(1):58-66. doi: 10.1094/PDIS-93-1-0058.
Fusarium wilt, a vascular wilt caused by Fusarium oxysporum, has been a serious problem for birdsfoot trefoil (Lotus corniculatus) production in parts of New York and Vermont since the 1970s, causing wilt, severe root necrosis, and rapid plant death. Analysis of F. oxysporum isolates causing this disease indicated that the pathogen has a unique host range relative to previously designated F. oxysporum formae speciales and is monophyletic. Pathogenic isolates from New York and Vermont caused severe vascular wilt of trefoil and moderate vascular wilt of pea but no disease on alfalfa, red clover, soybean, or dry bean. The host range of trefoil isolates was distinct from F. oxysporum isolates pathogenic to other legumes. F. oxysporum isolates pathogenic to trefoil belonged to a single vegetative compatibility group separate from nonpathogenic isolates and shared identical mitochondrial small subunit rDNA, translation elongation factor 1-alpha, and nuclear rDNA intergenic spacer haplotypes. Phylogenetic analysis of the concatenated sequence data assigned isolates pathogenic to trefoil to a single, well-supported clade distinct from other pathogenic F. oxysporum. We propose designating the fungus Fusarium oxysporum Schlechtendahl emend. Snyder & Hansen f. sp. loti forma specialis nova.
尖孢镰刀菌引起的枯萎病是一种维管束枯萎病，自20世纪70年代以来，一直是纽约州和佛蒙特州部分地区鸟足豆（百脉根）生产中的严重问题，会导致枯萎、严重的根坏死和植株迅速死亡。对引起该病的尖孢镰刀菌分离株的分析表明，该病原菌相对于先前指定的尖孢镰刀菌专化型具有独特的寄主范围，并且是单系的。来自纽约州和佛蒙特州的致病分离株导致三叶草严重维管束枯萎和豌豆中度维管束枯萎，但对苜蓿、红三叶、大豆或菜豆不致病。三叶草分离株的寄主范围与对其他豆科植物致病的尖孢镰刀菌分离株不同。对三叶草致病的尖孢镰刀菌分离株属于一个与非致病分离株不同的单一营养体亲和群，并且共享相同的线粒体小亚基rDNA、翻译延伸因子1-α和核rDNA基因间隔区单倍型。对串联序列数据的系统发育分析将对三叶草致病的分离株归为一个单一的、得到充分支持的分支，与其他致病尖孢镰刀菌不同。我们建议将该真菌命名为尖孢镰刀菌（Schlechtendahl）修订。斯奈德和汉森f. sp. loti forma specialis nova。
