不同硫酸钾用量对植烟土壤细菌群落的影响

Effects of Different Potassium Sulfate Levels on Bacterial Community of Tobacco Planting Soil

为研究不同硫酸钾用量对植烟土壤微生物的影响,采用连续8年田间定位试验分析了土壤细菌群落多样性。对各处理植烟土壤16S rRNA V3～V4区进行高通量测序,得到各处理植烟土壤细菌群落的α多样性指数、群落种类组成及丰度信息,并对群落组成及丰度进行了PCA聚类分析及UPGMA聚类分析,将排名前十优势细菌门与土壤pH、土壤酶活性、钾和硫含量进行相关性分析。结果表明:(1)与空闲地相比,不施肥连年栽烟土壤细菌数量降低;而施肥处理中,K2O的投入量为247.57 kg/hm^2,S的投入量为125.46 kg/hm^2时,细菌群落丰度、多样性和均匀度明显增加。(2)不同处理的土壤中变形菌门、酸杆菌门和放线菌门均为优势菌群,随着硫酸钾施用量的增多,酸杆菌门相对含量明显减少,而变形菌门与放线菌门均呈不同程度增加趋势。(3)细菌群落相似性分析结果表明,长期施用硫酸钾能显著改变土壤群落组成。(4)相关性分析表明,土壤pH、土壤蔗糖酶、脲酶活性、钾和硫含量对于该地区土壤细菌群落的丰度、多样性及优势种群相对丰度起着重要作用。

To study the effects of different potassium sulfate dosages on the bacterial community diversity of tobacco planting soils, soil bacterial community diversity was analyzed by consecutive field experiment for 8 years. High-throughput sequencing of the 16S rRNA V3-V4 region of each treated tobacco planting soil was carried out, and α diversity index, community species composition and abundance information of the bacterial communities were obtained. The community composition and abundance were analyzed by PCA cluster analysis and UPGMA cluster analysis. The correlations between the top ten dominant bacteria and soil pH, soil enzyme activity, potassium and sulfur content were analyzed. The results showed that:(1) Compared with the natural vegetation, the amount of bacteria of CK was reduced. In the fertilization treatments, the abundance, diversity and uniformity of the bacterial community increased significantly when the input of K2O was 247.57 kg/ha, and the input of S was 125.4 kg/ha.(2) Proteobacteria, Acidobacteria and Actinobacteria were the dominant bacteria in all treated planting soils of this experiment, and with the increase of potassium sulfate application, the relative content of the Acidobacteria was significantly reduced, while Proteobacteria and Actinobacteria increased in different degrees.(3) The results of bacterial community similarity analysis for each treatment showed that long-term application of potassium sulfate could significantly change the soil bacterial community composition.(4) Correlation analysis showed that soil pH, soil sucrase activity and urease activities, the content of potassium and sulfur played an important role in the abundance, diversity and relative abundance of soil bacterial communities in the region.