小黑麦对石油污染盐碱土壤细菌群落与石油烃降解的影响

为了研究小黑麦对石油污染盐碱土壤中的细菌群落与石油烃降解率的影响,采用高通量测序技术,设置0 g/kg,1 g/kg和5 g/kg三个石油浓度,以未种植小黑麦的土壤作为对照,对6组不同处理的盐碱土壤样品的细菌群落结构及其多样性进行测定,并分析土壤中的石油烃降解率。结果表明:在土壤石油浓度为1 g/kg和5 g/kg时,小黑麦根际土壤中的石油烃降解率相较对照组分别提高了36.67%和33.20%。从6个土壤样品中分别获得21398—27899条测序序列。在石油污染土壤中,小黑麦根际土壤的细菌群落多样性和丰度均大于对照组的土壤。同时,在"门","纲","属"的分类水平上,小黑麦根际土壤细菌群落中的一些根际细菌的相对丰度增加了,主要包括变形菌门(Proteobacteria)、酸杆菌门(Acidobacteria)、γ-变形菌纲(Gammaproteobacteria)、烷烃降解菌科-未命名菌属(Alcanivoracaceae_norank)、黄单胞菌属(Xanthomonas)、亚硝化单胞菌-不可培养菌属(Nitrosomonadaceae_unculture)等。有一些相对丰度增加的根际细菌是以石油及石油分解物为碳源的微生物。本研究证明种植小黑麦改变了石油污染盐碱土壤根际土壤细菌群落结构组成和多样性,促进了降解石油微生物群落的构建,显著提高了盐碱土壤石油污染的降解效果。研究结果为石油污染盐碱土壤的植物修复奠定了理论基础。

Effect of triticale (Triticale hexaploide L.) growth on the bacterial community and petroleum hydrocarbon degradation in petroleum-contaminated saline-alkali soil

In order to study the effect of triticale on the bacterial community and petroleum hydrocarbon degradation rate in petroleum-contaminated saline-alkali soil, three concentrations of petroleum with 0 g/kg, 1 g/kg and 5 g/kg were introduced into the research and non-triticale-planted soil was set as control group for corresponding concentration of petroleum which formed six different experiment groups. The high-throughput sequencing technology was utilized to study the structure and diversity of the microbial community of six soil samples and to analyze the petroleum hydrocarbon degradation rate. The results showed that the cultivation of triticale increased the degradation of petroleum hydrocarbon by 36.67% and 33.20% in the condition of 1 g/kg and 5 g/kg petroleum, respectively. 21398 to 27899 sequencing sequences were obtained from 6 soil samples. The diversity and abundance of the bacterial communities in the rhizosphere of triticale were higher than those of the soil without plant in the petroleum-contaminated soil. Moreover, the abundance of some rhizosphere bacteria increased in the classification level of "phylum", "class", "genus", such as Proteobacteria, Acidobacteria, Gamma-proteobacteriaria, Alcanivoracaceae_norank, Xanthomonas, Nitrosomonadaceae_unculture, etc. Some rhizosphere bacteria with the increased relative abundance are microorganisms that use petroleum and petroleum decomposition as carbon sources. This study proved that planting triticale changed the composition and diversity of bacterial community in rhizosphere soil of petroleum-contaminated saline-alkali soil, promoted the construction of petroleum-degrading microbial community, and significantly improved the degradation effect of petroleum-contaminated saline-alkali soil. The results laid a theoretical foundation for phytoremediation of petroleum-contaminated saline-alkali soils.