Bacterial spot is a disease that affects tomato worldwide reducing its yield and quality. It is caused by different Xanthomonas spp., among which is Xanthomonas vesicatoria. Copper-based bactericides are generally used to control this disease, although nowadays sustainable strategies are being searched to efficiently replace their use. Our aim was to select native bacteria from tomato rhizosphere with biocontrol properties against X. vesicatoria. We selected, characterized, and identified three novel strains, two closely related to Bacillus velezensis (VMA11p and VM05) and one closely related to Pseudomonas soli (VMAP1), that in vitro antagonized X. vesicatoria. We evaluated the efficacy of the three rhizobacteria and their cell-free supernatants to control bacterial spot using the model tomato-X. vesicatoria in plants grown in pots, in greenhouse conditions. Bacterial suspensions of VMA11p and VMAP1, applied to the soil by irrigation, significantly (P < 0.05) reduced bacterial spot severity by 53.9% and 44.2%, respectively. Nevertheless, the most effective strategy to control bacterial spot was achieved using the cell-free supernatant produced by VMA11p, VM05 or VMAP1 applied as foliar spray, which significantly (P < 0.05) reduced the severity of the disease by 98.5%, 94.2% and 75.2%, respectively. None of the treatments reduced the growth of tomato plants. Our results suggest that the use of these novel strains of Bacillus and Pseudomonas and/or their metabolic products could be used for the development of biocontrol strategies for the management of bacterial spot in tomato.

细菌性斑点病是一种影响全球番茄产量和质量的疾病。它是由不同的黄单胞菌属引起的，其中黄单胞菌属 vesicatoria。铜基杀菌剂通常用于控制这种疾病，尽管现在正在寻找可持续的策略来有效地替代它们的使用。我们的目标是从番茄根际中选择具有生物防治特性的天然细菌，以对抗X. vesicatoria。我们选择、表征并鉴定了三种新菌株，其中两种与Bacillus velezensis (VMA11p 和 VM05) 密切相关，另一种与Pseudomonas soli (VMAP1)密切相关，它们在体外拮抗水疱病。我们评估了三种根际细菌及其无细胞上清液在温室条件下在盆栽植物中使用模型番茄 - X. vesicatoria控制细菌斑点的功效。通过灌溉施用于土壤的 VMA11p 和 VMAP1 细菌悬浮液分别显着（P  < 0.05）将细菌斑点严重程度降低了 53.9% 和 44.2%。尽管如此，使用由 VMA11p、VM05 或 VMAP1 产生的无细胞上清液作为叶面喷洒是控制细菌斑点的最有效策略，这显着（P < 0.05) 使疾病的严重程度分别降低了 98.5%、94.2% 和 75.2%。没有一种处理会减少番茄植株的生长。我们的研究结果表明，这些新的芽孢杆菌和假单胞菌菌株和/或其代谢产物的使用可用于开发番茄细菌性斑点病管理的生物防治策略。