Sahin F, Miller S A
Department of Plant Pathology, The Ohio State University, OARDC, Wooster 44691.
Plant Dis. 1998 Feb;82(2):262. doi: 10.1094/PDIS.1998.82.2.262B.
Bacterial leaf spot of lettuce (Lactuca sativa L.) caused by Xanthomonas campestris pv. vitians (proposed new names X. axonopodis pv. vitians / X. hortorum pv. vitians) is an economically important disease in many areas of the world (1,2). Serious outbreaks occurred in Ohio in 1995 and 1996. The primary sources of the causal agent are presumed to be contaminated seed and infected plant debris in the field. Once the disease is present in a field, crop rotation is required to decrease primary inoculum of the pathogen. Therefore, appropriate crop rotation sequences need to be determined based on the host range of the pathogen. Some vegetable crops, including tomato, pepper, cabbage, collard, kale, radish, and horseradish, were tested for susceptibility to four representative strains of X. campestris pv. vitians by spray inoculation in the greenhouse. Typical symptoms of bacterial leaf spot were observed on tomato and pepper plants 8 days after inoculation, whereas the other crops did not develop diagnostic symptoms. The pathogen was reisolated and Koch's postulates were completed on tomato and pepper. This is the first report that X. campestris pv. vitians strains can cause bacterial spot disease on tomato and pepper. References: (1) C. L. Patterson et al. Plant Dis. 70:982, 1986. (2) L. Vauterin et al. Int. J. Syst. Bacteriol. 45:472, 1995.
由野油菜黄单胞菌莴苣致病变种（提议的新名称为野油菜黄单胞菌轴突变种/园艺黄单胞菌莴苣致病变种）引起的生菜细菌性叶斑病，在世界许多地区都是一种具有经济重要性的病害（1,2）。1995年和1996年在俄亥俄州发生了严重疫情。病原体的主要来源据推测是受污染的种子和田间受感染的植物残体。一旦田间出现这种病害，就需要进行作物轮作以减少病原体的初侵染源。因此，需要根据病原体的寄主范围来确定合适的作物轮作顺序。通过在温室中喷雾接种，对包括番茄、辣椒、卷心菜、羽衣甘蓝、甘蓝、萝卜和辣根在内的一些蔬菜作物进行了对野油菜黄单胞菌莴苣致病变种四个代表性菌株的敏感性测试。接种8天后，在番茄和辣椒植株上观察到了细菌性叶斑病的典型症状，而其他作物未出现诊断症状。从番茄和辣椒上重新分离出病原体并完成了柯赫氏法则验证。这是关于野油菜黄单胞菌莴苣致病变种菌株可引起番茄和辣椒细菌性斑点病的首次报道。参考文献：(1) C. L. Patterson等人，《植物病害》70:982，1986年。(2) L. Vauterin等人，《国际系统细菌学杂志》45:472，1995年。
