Department of Horticulture, Northeast Agricultural University, Harbin, China.
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northeast Region), Ministry of Agriculture, Harbin, China.
Sci Rep. 2018 Mar 21;8(1):4929. doi: 10.1038/s41598-018-23406-2.
Soil microorganisms are key drivers of plant productivity in terrestrial ecosystems, yet controls on their diversities and abundances are not fully elucidated. Phenolic acids, released through plant root exudation and residues decomposition, are usually referred as autotoxins of several crops, including cucumber. In this study, effects of vanillic acid (VA) on cucumber rhizosphere microbial communities were investigated by treating cucumber seedlings with VA every two days for five times. Amplicon sequencing, PCR-denaturing gradient gel electrophoresis and quantitative PCR were used to analyzed the 16S rRNA genes of total bacterial, Pseudomonas and Bacillus spp. communities. Results showed that VA at 0.05 μmol g soil changed total bacterial community diversity and composition. In particular, VA inhibited the relative abundances of genera with plant-beneficial potentials, such as Bacillus and Lysobacter spp. Moreover, VA changed Pseudomonas and Bacillus spp. community compositions by altering the number and/or relative abundances of their OTUs; and decreased Bacillus spp. community abundance at 0.02 to 0.2 μmol g soil and Pseudomonas spp. community abundance at 0.2 μmol g soil. Overall, VA changed cucumber seedling rhizosphere total bacterial, Pseudomonas and Bacillus spp. communities, which maybe be associated with the adverse effects of VA on cucumber growth under soil conditions.
土壤微生物是陆地生态系统中植物生产力的关键驱动因素，但它们的多样性和丰度的控制机制尚未完全阐明。通过植物根系分泌和残体分解释放的酚酸通常被认为是几种作物（包括黄瓜）的自毒物质。在这项研究中，通过每隔两天用香草酸（VA）处理黄瓜幼苗五次，研究了 VA 对黄瓜根际微生物群落的影响。使用扩增子测序、PCR-变性梯度凝胶电泳和定量 PCR 分析了总细菌、假单胞菌和芽孢杆菌属群落的 16S rRNA 基因。结果表明，土壤中 0.05 μmol g 的 VA 改变了总细菌群落的多样性和组成。特别是，VA 抑制了具有植物有益潜力的属的相对丰度，如芽孢杆菌属和赖氨酸杆菌属。此外，VA 通过改变其 OTUs 的数量和/或相对丰度来改变假单胞菌属和芽孢杆菌属群落的组成；并降低了土壤中 0.02 至 0.2 μmol g 的芽孢杆菌属群落丰度和土壤中 0.2 μmol g 的假单胞菌属群落丰度。总的来说，VA 改变了黄瓜幼苗根际的总细菌、假单胞菌和芽孢杆菌属群落，这可能与 VA 在土壤条件下对黄瓜生长的不利影响有关。
