Chemicals used for plant health may have negative impacts on humans, animals and environment, thus antagonistic microorganisms have become popular for the control of plant diseases. Acidovorax citrulli (Ac)-induced melon bacterial fruit blotch (BFB) disease poses serious threats worldwide to the production of cucurbits, especially melon (Cucumis melo) and watermelon (Citrullus lanatus). In this study, effects of 14 different antagonistic bacteria isolated from the phyllosphere of melon and watermelon were tested against BFB through seed treatments under growth chamber conditions and through foliage sprays under greenhouse conditions. When seeds were treated with antagonistic bacteria, seven of them reduced disease incidence by over 50% and disease severity by about 70%. Then, these seven antagonists were sprayed on melon leaves twice (1 and 15 days after transplanting) under greenhouse conditions and disease development was monitored weekly for five weeks. As compared to the control, Pseudomonas oryzihabitans Antg-12, isolated from watermelon leaf, reduced both disease severity (55.85%) and the area under the disease curve (AUDPC) (66.85%), and increased yield by about 41%. In the present study it was shown that certain bacterial biocontrol agents can substantially reduce disease and, when added into integrated management of BLB, may well provide very useful solutions to disease control. To further prove this, studies using the antagonists under open field conditions are planned.

用于植物健康的化学品可能对人类、动物和环境产生负面影响，因此拮抗微生物已成为控制植物病害的流行方法。敏捷食citrulli（AC）诱导的瓜细菌性果斑病（BFB）疾病造成全球严重威胁到生产瓜类，特别是甜瓜（香瓜），西瓜（西瓜）。在这项研究中，通过生长室条件下的种子处理和温室条件下的叶面喷洒，测试了从甜瓜和西瓜的叶际分离的 14 种不同拮抗细菌对 BFB 的影响。当用拮抗细菌处理种子时，其中 7 个种子的发病率降低了 50% 以上，疾病严重程度降低了约 70%。然后，在温室条件下将这七种拮抗剂喷洒在甜瓜叶上两次（移植后 1 天和 15 天），每周监测病害发展，持续五周。与对照相比，Pseudomonas oryzihabitans从西瓜叶中分离的 Antg-12 降低了疾病严重程度 (55.85%) 和疾病曲线下面积 (AUDPC) (66.85%)，并将产量提高了约 41%。在本研究中，表明某些细菌生物防治剂可以显着减少疾病，并且当添加到 BLB 的综合管理中时，很可能为疾病控制提供非常有用的解决方案。为了进一步证明这一点，计划在露天条件下使用拮抗剂进行研究。