Department of Plant Science, McGill University, Macdonald Campus, 21,111 Lakeshore Road, Sainte-Anne-de-Bellevue, Québec, H9X 3V9, Canada.
Department of Plant Science, McGill University, Macdonald Campus, 21,111 Lakeshore Road, Sainte-Anne-de-Bellevue, Québec, H9X 3V9, Canada.
Syst Appl Microbiol. 2018 Nov;41(6):629-640. doi: 10.1016/j.syapm.2018.06.004. Epub 2018 Jul 3.
Plants are chronically associated with microorganisms, residing all tissues. Holonomic analysis of diversity of established rhizobacteria in uncultivated plants is scarce. Thus, the present study was conducted to access the root-associated bacterial diversity of 6 crops (maize, canola, soybean, reed canarygrass, alfafa, and miscanthus) and 20 uncultivated plant species in the region of Sainte-Anne-de-Bellevue, Québec, Canada, using pure-culture methods. Based on 16S rRNA gene sequence analysis, 446 bacterial isolates were distributed onto four phyla (Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes), 32 families and 90 genera. Proteobacteria constituted the largest group of isolates (240), 40% of ectophytic and 61% of endophytic bacteria. Representatives of the genera Bacillus and Pseudomonas dominated in rhizosphere soil; Microbacterium and Pseudomonas were the predominant endophytes. Some genera were associated with specific plant species, such as Stenotrophomonas, Yersinia, Labrys and Luteibacter. Several endophytes were occasionally observed in the rhizosphere, and vice versa. This is the first survey of culturable endophytic bacteria associated with uncultivated plants in Québec. The culturable bacterial community studied herein are assumed to represent a portion of the entire phytomicrobiome of the evaluated plants. Results confirmed that the crops and uncultivated plants of Québec represent an extremely rich reservoir of diverse rhizobacteria.
植物与微生物长期共生，存在于所有组织中。对于未培养植物中已建立的根际细菌多样性的整体分析还很少。因此，本研究采用纯培养方法，对加拿大魁北克圣安妮德贝勒维尤地区的 6 种作物（玉米、油菜、大豆、柳枝稷、紫花苜蓿和芒草）和 20 种未培养植物的根际相关细菌多样性进行了研究。基于 16S rRNA 基因序列分析，从 446 个细菌分离株中分布在 4 个门（变形菌门、厚壁菌门、放线菌门和拟杆菌门）、32 个科和 90 个属中。变形菌门构成了最大的分离株群体（240 个），占外生菌的 40%和内生菌的 61%。芽孢杆菌属和假单胞菌属代表的种在根际土壤中占优势；而微杆菌属和假单胞菌属是主要的内生菌。一些属与特定的植物物种相关，如 Stenotrophomonas、Yersinia、Labrys 和 Luteibacter。一些内生菌偶尔也会在根际中观察到，反之亦然。这是魁北克首次对未培养植物的可培养内生细菌进行调查。本研究中研究的可培养细菌群落被认为代表了所评估植物整个植物微生物组的一部分。研究结果证实，魁北克的作物和未培养植物代表了丰富多样的根际细菌的丰富资源库。
