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栎枯萎病自1942年以来,一直在美国的东部和中部的栎树林中流行,造成严重的损失,使阔叶树的生长受到很大的威胁。寄主范围:栎枯萎病主要危害壳斗科的栎属(Quercus)植物,约有50多个种或品种。此外,栗属(Castanea)、栲属(Castanopsis)和Lythocarpus属也已证实是感病的。症状:栎树感病后,首先是树冠顶部的老叶发生轻度的皱缩,呈暗灰色,最后变为铜褐色。症状逐渐地由树冠向基部蔓延,病叶不断地脱落。不同的栎类,感病的程度不同,所表
Fusarium wilt has been endemic to oak forests in the eastern and central United States since 1942, causing serious losses and threatening the growth of broad-leaved trees. Host Range: Quercus fusarium wilt mainly affects Quercus plants in the Fagaceae, with more than 50 species or varieties. In addition, Castanea, Castanopsis and Lythocarpus also have proven to be susceptible. Symptoms: After the oak tree is affected, the first is the slight shrinkage of the old leaves on the top of the crown, dark gray and finally copper brown. Symptoms gradually spread from the crown to the base, sick leaves continue to fall off. Different oaks, different levels of susceptibility, as shown