Ma Yi-Nan, Gu Yi-Lin, Liu Jing, Zhang Yuqin, Wang Xinwei, Xia Zhenyuan, Wei Hai-Lei
Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China.
Zunyi Tobacco Company of Guizhou Provincial Tobacco Corporation, Zunyi, China.
Front Plant Sci. 2023 Apr 3;14:1152639. doi: 10.3389/fpls.2023.1152639. eCollection 2023.
The black shank disease seriously affects the health of tobacco plants. Conventional control methods have limitations in terms of effectiveness or economic aspects and cause public health concerns. Thus, biological control methods have come into the field, and microorganisms play a key role in suppressing tobacco black shank disease.
In this study, we examined the impact of soil microbial community on black shank disease basing on the structural difference of bacterial communities in rhizosphere soils. We used Illumina sequencing to compare the bacterial community diversity and structure in different rhizosphere soil samples in terms of healthy tobacco, tobacco showing typical black shank symptoms, and tobacco treated with the biocontrol agent, Bacillus velezensis S719.
We found that Alphaproteobacteria in the biocontrol group, accounted for 27.2% of the ASVs, was the most abundant bacterial class among three groups. Heatmap and LEfSe analyses were done to determine the distinct bacterial genera in the three sample groups. For the healthy group, Pseudomonas was the most significant genus; for the diseased group, Stenotrophomonas exhibited the strongest enrichment trend, and Sphingomonas showed the highest linear discriminant analysis score, and was even more abundant than Bacillus; for the biocontrol group, Bacillus, and Gemmatimonas were the largely distributed genus. In addition, co-occurrence network analysis confirmed the abundance of taxa, and detected a recovery trend in the network topological parameters of the biocontrol group. Further functional prediction also provided a possible explanation for the bacterial community changes with related KEGG annotation terms.
These findings will improve our knowledge of plant-microbe interactions and the application of biocontrol agents to improve plant fitness, and may contribute to the selection of biocontrol strains.
黑胫病严重影响烟草植株的健康。传统防治方法在有效性或经济方面存在局限性，并引发了公众健康问题。因此，生物防治方法进入该领域，微生物在抑制烟草黑胫病中发挥关键作用。
在本研究中，我们基于根际土壤细菌群落的结构差异，研究了土壤微生物群落对黑胫病的影响。我们使用Illumina测序技术，比较了健康烟草、表现出典型黑胫病症状的烟草以及用生物防治剂贝莱斯芽孢杆菌S719处理的烟草的不同根际土壤样本中的细菌群落多样性和结构。
我们发现，生物防治组中的变形菌门α亚群占可操作分类单元（ASVs）的27.2%，是三组中最丰富的细菌类群。通过热图和线性判别分析效应大小（LEfSe）分析来确定三个样本组中不同的细菌属。对于健康组，假单胞菌属是最显著的属；对于患病组，嗜麦芽窄食单胞菌呈现出最强的富集趋势，鞘氨醇单胞菌属显示出最高的线性判别分析得分，且比芽孢杆菌属更为丰富；对于生物防治组，芽孢杆菌属和芽单胞菌属是分布广泛的属。此外，共现网络分析证实了分类单元的丰度，并检测到生物防治组网络拓扑参数的恢复趋势。进一步的功能预测也用相关的京都基因与基因组百科全书（KEGG）注释术语为细菌群落变化提供了可能的解释。
这些发现将增进我们对植物 - 微生物相互作用以及生物防治剂应用以提高植物适应性的认识，并可能有助于生物防治菌株的选择。
