Abstract Bacterial spot of tomato (BST), caused by Xanthomonas perforans, is one of the most serious diseases in fresh market tomato production in Florida, and currently available management measures are largely ineffective or insufficient. Using small molecule compounds has been shown to be promising in management of BST. Carvacrol is a plant-derived small molecule, which is effective against many human and plant pathogens. In this study, we evaluated the efficacy of carvacrol for control of BST in vitro, in the greenhouse and in field trials. In the laboratory, X. perforans strain used in this study was able to grow on nutrient agar (NA) amended with CuSO4 at 400 mg L−1, which proved that this X. perforans strain was copper resistant. Our results also showed that the minimum inhibitory concentration (MIC) of carvacrol was 32 mg L−1 and its minimum bactericidal concentration (MBC) was 64 mg L−1. Carvacrol increased the sensitivity of the copper-resistant X. perforans strain to copper. In the leaf disc assay, carvacrol combined with copper reduced recovery of X. perforans from tomato leaf discs. Seed priming with carvacrol at 32 mg L−1 was found to be effective in promoting seed germination and seedling vigor of tomato. In greenhouse assays, carvacrol foliar applied alone or in combination with copper significantly (P

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小分子复合香芹酚防治抗铜穿孔黄单胞菌引起的番茄菌斑病

摘要 由穿孔黄单胞菌引起的番茄细菌性斑点病（BST）是佛罗里达州新鲜市场番茄生产中最严重的病害之一，目前可用的管理措施大多无效或不足。使用小分子化合物已被证明在管理 BST 方面很有前景。Carvacrol 是一种植物来源的小分子，对许多人类和植物病原体有效。在这项研究中，我们评估了香芹酚在体外、温室和田间试验中控制 BST 的功效。在实验室中，本研究中使用的 X. perforans 菌株能够在用 400 mg L-1 的 CuSO4 修正的营养琼脂 (NA) 上生长，这证明该 X. perforans 菌株具有铜抗性。我们的结果还表明香芹酚的最低抑菌浓度 (MIC) 为 32 mg L-1，其最低杀菌浓度 (MBC) 为 64 mg L-1。香芹酚增加了耐铜的 X. perforans 菌株对铜的敏感性。在叶盘试验中，香芹酚与铜结合降低了番茄叶盘中 X. perforans 的回收率。发现用 32 mg L-1 香芹酚引发种子可有效促进番茄种子萌发和幼苗活力。在温室试验中，香芹酚叶面单独施用或与铜联合施用效果显着（P 发现用 32 mg L-1 香芹酚引发种子可有效促进番茄种子萌发和幼苗活力。在温室试验中，香芹酚叶面单独施用或与铜联合施用效果显着（P 发现用 32 mg L-1 香芹酚引发种子可有效促进番茄种子萌发和幼苗活力。在温室试验中，香芹酚叶面单独施用或与铜联合施用效果显着（P