Zhu Shuangxi, Chang Xiaojian, Liu Nana, He Yanhui, Wang Jianwen, Wu Zhansheng
Xi'an Key Laboratory of Textile Chemical Engineering Auxiliaries, Key Laboratory of Textile Dyeing Wastewater Treatment Universities of Shaanxi Province, School of Environmental and Chemical Engineering, Engineering Research Center of Biological Resources Development and Pollution Control Universities of Shaanxi Province, Xi'an Polytechnic University, Xi'an, China.
Agricultural Technology Extension Center of Xi'an, Xi'an, China.
Front Microbiol. 2025 Apr 30;16:1559380. doi: 10.3389/fmicb.2025.1559380. eCollection 2025.
Bacterial wilt caused by seriously affects the healthy growth of tomato seedlings. Biocontrol microbes have been used to manage tomato bacterial wilt. Herein, we aim to investigate the behavior of the Rs-5 and SL-44 composite microbial agent (EB) in the rhizosphere soil, and assess its impact on both the soil microbial community and tomato plant growth in this study.
The plate confrontation experiment and the pot experiment were respectively used to explore the control ability of EB against and bacterial wilt disease. The absolute quantitative PCR (AQ-PCR) was employed to investigate the migration ability of EB in the rhizosphere of tomatoes, and the chemotactic response of EB to tomato root exudates was analyzed by the swimming plate method. Scanning electron microscopy was utilized to study the biofilm formation of EB during its colonization on the root surface of tomatoes. Finally, high-throughput sequencing was adopted to analyze the impact of EB on the microbial community in the rhizosphere soil of tomatoes after being infected by .
The absolute quantitative PCR and scanning electron microscope showed that the EB could migrate and efficiently colonize the elongation zone of tomato roots to form a biofilm. In addition, the EB exhibits a chemotactic response to tomato root exudates like sucrose, leucine, glutamic acid, and aspartic acid. The pot experiment demonstrated that the EB can reduce the incidence of tomato bacterial wilt from 77.78% to 22.22%, and significantly increase the biomass, physicochemical properties, and rhizosphere soil nutrient contents of tomato seedlings. Besides, the relative abundance of beneficial bacteria such as , , and increased, and the fungi community diversity was improved.
Overall, the EB can reduce the amount of in rhizosphere soil, and then control tomato bacterial wilt directly. Besides, the EB can migrate to the root under the induction of tomato root exudates and colonize on the root surface efficiently, thereby indirectly regulating the soil microbial community structure and controlling tomato bacterial wilt.
由[病原菌名称未给出]引起的番茄青枯病严重影响番茄幼苗的健康生长。生物防治微生物已被用于防治番茄青枯病。在此，我们旨在研究Rs - 5和SL - 44复合微生物制剂（EB）在根际土壤中的行为，并评估其对土壤微生物群落和番茄植株生长的影响。
分别采用平板对峙试验和盆栽试验探究EB对[病原菌名称未给出]和番茄青枯病的防治能力。采用绝对定量PCR（AQ - PCR）研究EB在番茄根际的迁移能力，并用平板游动法分析EB对番茄根系分泌物的趋化反应。利用扫描电子显微镜研究EB在番茄根表面定殖过程中的生物膜形成情况。最后，采用高通量测序分析EB对[病原菌名称未给出]侵染后番茄根际土壤微生物群落的影响。
绝对定量PCR和扫描电子显微镜显示，EB能够迁移并有效定殖于番茄根的伸长区形成生物膜。此外，EB对蔗糖、亮氨酸、谷氨酸和天冬氨酸等番茄根系分泌物表现出趋化反应。盆栽试验表明，EB可将番茄青枯病发病率从77.78%降至22.22%，并显著增加番茄幼苗的生物量、理化性质和根际土壤养分含量。此外，有益细菌如[细菌名称未给出]、[细菌名称未给出]、[细菌名称未给出]和[细菌名称未给出]的相对丰度增加，真菌群落多样性得到改善。
总体而言，EB可减少根际土壤中[病原菌名称未给出]的数量，进而直接防治番茄青枯病。此外，EB可在番茄根系分泌物诱导下迁移至根部并有效定殖于根表面，从而间接调节土壤微生物群落结构并防治番茄青枯病。
