Shandong Provincial Engineering and Technology Research Center for Wild Plant Resources Development and Application of Yellow River Delta, College of Biological and Environmental Engineering, Binzhou University, Binzhou 256603, China; Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta, Binzhou University, Binzhou 256603, China.
Zhuhai Precision Medical Center, Zhuhai People's Hospital (Zhuhai hospital affiliated with Jinan University), Zhuhai 519000, China.
Sci Total Environ. 2021 May 1;767:144340. doi: 10.1016/j.scitotenv.2020.144340. Epub 2020 Dec 29.
Phragmites australis and Chloris virgata are native, dominant, salt-tolerant grass species that grow in the Yellow River Delta, China, and have potential applications in the phytoremediation of petroleum-polluted saline soil. The characteristics of endophytic bacterial communities of Phragmites australis and Chloris virgata and their functions in hydrocarbon degradation and plant growth promotion have been studied using both high-throughput sequencing and conventional microbial techniques. Through 16S rRNA gene amplicon sequencing, we found five bacterial phyla that were dominant among the endophytic bacterial communities of the two grass species, including Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, and Tenericutes. The phylum Proteobacteria was common among the endophytic bacterial communities of the two grass species. The diversity in the endophytic bacterial community of Chloris virgata was generally higher than that in the community of Phragmites australis. Thirty-eight hydrocarbon-degrading endophytic bacteria were isolated from the two grasses via culturing techniques. Based on phylogenetic analyses, the bacterial isolates were classified into the phyla Proteobacteria, Firmicutes, and Actinobacteria. The majority of strains belonged to the genera Bacillus and Pseudomonas. More than 70% of the isolates of hydrocarbon-degrading endophytes exhibited the ability to stimulate plant growth. These isolates mainly belonged to Bacillus sp., Pseudomonas sp., Beijerinckia sp., Serratia sp., Acinetobacter sp., Microbacterium sp., and Rhizobium sp. Altogether, the present study revealed that Phragmites australis and Chloris virgata growing on petroleum-polluted saline soil in the Yellow River Delta harbor several diverse species of endophytic bacteria and serve as novel sources of beneficial bacteria and hydrocarbon degradation.
芦苇和虉草是生长在中国黄河三角洲的本地、优势、耐盐草本植物，具有修复石油污染盐碱土壤的潜力。本研究采用高通量测序和常规微生物技术，研究了芦苇和虉草内生细菌群落的特征及其在烃类降解和植物促生中的功能。通过 16S rRNA 基因扩增子测序，我们发现，在这两种禾本科植物的内生细菌群落中，有五个细菌门占主导地位，包括变形菌门、放线菌门、厚壁菌门、拟杆菌门和无壁菌门。两个禾本科植物的内生细菌群落中普遍存在变形菌门。虉草内生细菌群落的多样性普遍高于芦苇。通过培养技术从这两种植物中分离出 38 株烃类降解内生细菌。基于系统发育分析，细菌分离株被分类为变形菌门、厚壁菌门和放线菌门。大多数菌株属于芽孢杆菌属和假单胞菌属。超过 70%的烃类降解内生菌具有刺激植物生长的能力。这些分离株主要属于芽孢杆菌属、假单胞菌属、贝日阿托氏菌属、沙雷氏菌属、不动杆菌属、微杆菌属和根瘤菌属。总之，本研究表明，生长在黄河三角洲石油污染盐碱土壤上的芦苇和虉草蕴藏着多种内生细菌，是有益细菌和烃类降解的新来源。
