Bacterial halo blight caused by Pseudomonas syringae pv. garcae is a limiting disease to the coffee crop due to difficulty and low efficiency of the chemical control on field conditions. The simultaneous use of windbreaks and resistant cultivars seem to be the most appropriate measure of disease management. Although the bacterial halo blight resistance has been extensively studied in Coffea arabica, information about the reaction of C. canephora germplasm is not available. Thus, the objective of this study was to identify resistance sources to the bacterial halo blight in C. canephora germplasm, for use in breeding programs. Several commercial cultivars, botanical varieties, clones and hybrids of C. canephora were tested against a highly virulent P. syringae pv. garcae strain through artificial inoculations in greenhouse conditions. Only 1.4% of 2.421 evaluated plants were considered resistant to the disease. Our results showed the alarming vulnerability of Coffea canephora crop and germplasm to the bacterial halo blight from Brazil and the need to select resistant cultivars.

中文翻译：

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Coffea canephora 品种和种质对 Pseudomonas syringae pv. 剧毒菌株的惊人脆弱性。garcae，巴西咖啡细菌性晕枯病的原因

由丁香假单胞菌光伏引起的细菌晕枯病。由于田间条件下化学防治的困难和低效率，garcae 是咖啡作物的一种限制性病害。同时使用防风林和抗病品种似乎是最合适的疾病管理措施。尽管已经在小粒咖啡中广泛研究了细菌性晕枯病抗性，但尚无关于 C. canephora 种质反应的信息。因此，本研究的目的是确定 C. canephora 种质中细菌性晕枯病的抗性来源，以用于育种计划。C. canephora 的几个商业栽培品种、植物品种、无性系和杂交种针对高毒力 P. syringae pv 进行了测试。在温室条件下通过人工接种获得garcae菌株。只有 2 的 1.4%。421 株被评估植物被认为对该病具有抗性。我们的研究结果表明，Coffea canephora 作物和种质对来自巴西的细菌性光晕枯萎病的脆弱性令人震惊，并且需要选择抗性品种。