Zhang Jianhui, Zhang Zhidong, Wen Yue, Zhu Jing, Wufuerjiang Abudusufuer, Tian Jia
College of Horticulture, Xinjiang Agricultural University, Urumqi 830052, China.
Xinjiang Key Laboratory of Special Environmental Microbioogy, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China.
Int J Mol Sci. 2025 May 7;26(9):4438. doi: 10.3390/ijms26094438.
Fire blight, caused by , poses a significant threat to the sustainable development of the Korla Xiangli (. Yu) industry. In this study, we used multiple experimental approaches to comprehensively evaluate the efficacy of three antagonistic bacterial strains-namely, Mg-7 (), Rt-10 (), and Rt-11 ()-in controlling fire blight. In vitro plate inhibition assays revealed that Mg-7 exhibited the largest inhibition zone diameter, exceeding Rt-10 and Rt-11 in this respect, suggesting its strong antifungal potential. In therapeutic tests conducted on detached leaves, Mg-7 achieved the highest control efficiency, 60.39%, while Rt-10 demonstrated the greatest efficiency (76.96%) in protective tests. Conversely, in therapeutic trials focusing on detached branches, Mg-7 showed a control efficiency of 45.90%, whereas Rt-11 exhibited the highest efficiency, 86.27%, in protective trials. Furthermore, in vitro evaluations indicated that the Mg-7 treatment significantly reduced the lesion spread area. Enzymatic analyses revealed that, in the leaf protection assay, catalase activity (CAT) demonstrated significant increases of 65.56%, 85.46%, and 45.55% under the Mg-7, RT-10, and RT-11 treatments, respectively, when compared with the EA control group on day four. Correspondingly, in the branch protection assay, polyphenol oxidase (PPO) activity displayed marked elevations of 62.84%, 52.06%, and 82.69% under identical experimental conditions at the same time point. These treatments not only upregulated antioxidant enzyme activities but also significantly reduced malondialdehyde (MDA) content, effectively mitigating oxidative damage while enhancing foliar and branch resistance to fire blight infection. Field trials conducted in outdoor orchards confirmed that the Mg-7 bacterial suspension provided more effective and stable control against fire blight than Rt-10 and Rt-11. Overall, Mg-7 shows significant potential for use as a biocontrol agent for managing fire blight because of its high efficacy, stability, and ability to enhance plant defense responses.
由[病原菌名称未给出]引起的火疫病，对库尔勒香梨（[品种名称未给出]）产业的可持续发展构成了重大威胁。在本研究中，我们采用了多种实验方法，全面评估了三种拮抗细菌菌株——即Mg - 7（[菌株具体名称未给出]）、Rt - 10（[菌株具体名称未给出]）和Rt - 11（[菌株具体名称未给出]）——对火疫病的防治效果。体外平板抑制试验表明，Mg - 7的抑菌圈直径最大，在这方面超过了Rt - 10和Rt - 11，表明其具有很强的抗真菌潜力。在离体叶片上进行的治疗试验中，Mg - 7的防治效果最高，为60.39%，而在保护试验中，Rt - 10表现出最高的防治效果（76.96%）。相反，在针对离体枝条的治疗试验中，Mg - 7的防治效果为45.90%，而在保护试验中，Rt - 11表现出最高的防治效果，为86.27%。此外，体外评估表明，Mg - 7处理显著减少了病斑扩展面积。酶活性分析显示，在叶片保护试验中，与第4天的EA对照组相比，在Mg - 7、RT - 10和RT - 11处理下，过氧化氢酶活性（CAT）分别显著提高了65.56%、85.46%和45.55%。相应地，在枝条保护试验中，在相同实验条件下的同一时间点，多酚氧化酶（PPO）活性显著提高了62.84%、52.06%和82.69%。这些处理不仅上调了抗氧化酶活性，还显著降低了丙二醛（MDA）含量，有效减轻了氧化损伤，同时增强了叶片和枝条对火疫病感染的抗性。在室外果园进行的田间试验证实，Mg - 7菌悬液对火疫病的防治比Rt - 10和Rt - 11更有效、更稳定。总体而言，Mg - 7因其高效、稳定以及能够增强植物防御反应，在作为防治火疫病的生物防治剂方面具有显著潜力。
