Identification of Isolates that Cause a Leaf Spot Disease of Brassicas as Xanthomonas campestris pv. raphani and Pathogenic and Genetic Comparison with Related Pathovars.
Identification of Isolates that Cause a Leaf Spot Disease of Brassicas as Xanthomonas campestris pv. raphani and Pathogenic and Genetic Comparison with Related Pathovars.
复制标题
引起芸苔属叶斑病的分离株 Xanthomonas Campestris pv. 的鉴定。
DOI：
10.1094/phyto-96-0735
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发表时间：
2006
期刊：
影响因子：
3.2
通讯作者：
S. J. Roberts
中科院分区：
文献类型：
--
作者：
J. Vicente;B. Everett;S. J. Roberts
摘要：25株黄单胞菌分离株，其中一些分离株被鉴定为campestris pv。犰狳科或pv。当喷洒接种到至少一个甘蓝品种上时，引起离散的叶斑病症状。其中12株黄单胞菌和另外4株黄单胞菌分别接种于21个不同的植物品种上，包括辣根（Armoracia rusticana）、萝卜（Raphanus sativus）和番茄（Lycopersicon esculentum）。将剩下的13株叶斑病分离株喷雾接种到10个植物种/品种亚群上。该叶斑病菌株对几种芸苔属植物、萝卜和番茄具有很强的侵染性，在叶脉、叶柄和茎上产生叶斑和深色凹陷性病变。根据几种芸苔属和萝卜品种的差异反应，将叶斑病分离菌株分为3个小种，以1、3小种为主。建立了一个鉴别系列来确定分离菌株的种型，并提出了一种基于病原菌种中两个无毒基因和差异寄主中两个匹配抗性基因相互作用的基因对基因模型。采用重复dna聚合酶链反应指纹图谱技术，对黄单胞菌病原菌分离株和叶斑病分离株的遗传多样性进行了分析。虽然每个小种内部存在变异，但叶斑病分离株与油菜系是分开聚集的。定隔离。我们建议将引起芸苔属无维管叶斑病的油菜X. campestris分离株鉴定为pv。Raphani而不是pv。armoraciae。油菜弧菌的小种型菌株和新病原型菌株。Raphani被提议。
ABSTRACT Twenty-five Xanthomonas isolates, including some isolates received as either X. campestris pv. armoraciae or pv. raphani, caused discrete leaf spot symptoms when spray-inoculated onto at least one Brassica oleracea cultivar. Twelve of these isolates and four other Xanthomonas isolates were spray- and pin-inoculated onto 21 different plant species/cultivars including horseradish (Armoracia rusticana), radish (Raphanus sativus), and tomato (Lycopersicon esculentum). The remaining 13 leaf spot isolates were spray-inoculated onto a subset of 10 plant species/cultivars. The leaf spot isolates were very aggressive on several Brassica spp., radish, and tomato causing leaf spots and dark sunken lesions on the middle vein, petiole, and stem. Based on the differential reactions of several Brassica spp. and radish cultivars, the leaf spot isolates were divided into three races, with races 1 and 3 predominating. A differential series was established to determine the race-type of isolates and a gene-for-gene model based on the interaction of two avirulence genes in the pathogen races and two matching resistance genes in the differential hosts is proposed. Repetitive-DNA polymerase chain reaction-based fingerprinting was used to assess the genetic diversity of the leaf spot isolates and isolates of closely related Xanthomonas pathovars. Although there was variability within each race, the leaf spot isolates were clustered separately from the X. campestris pv. campestris isolates. We propose that X. campestris isolates that cause a nonvascular leaf spot disease on Brassica spp. should be identified as pv. raphani and not pv. armoraciae. Race-type strains and a neopathotype strain for X. campestris pv. raphani are proposed.