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【目的】研究盐胁迫下耐盐植物根际微生物群落变化情况。【方法】基于温室盆栽试验,结合植株生长测定、土壤理化性质分析、PCR-DGGE图谱技术、香农多样性分析、主成分分析等方法,研究NaCl(0、2.9、8.8 g/L)溶液胁迫下,耐盐果树滨梅根际和非根际土壤细菌多样性变化情况及变化规律,以及滨梅生长及土壤理化性质变化。【结果】盐胁迫60 d后,高浓度NaCl(8.8 g/L)溶液处理下滨梅根际土壤细菌16s rDNA序列变性梯度凝胶电泳(DGGE)图谱中的条带亮度、多样性指数、均匀度指数和丰富度指数最高,非根际土壤中的条带数明显减少,条带亮度变暗,丰富度指数最低。对DGGE谱带进行聚类分析发现,不同谱带间具有较高的相似性(>62%),其中根际盐处理试验组和根际对照组可聚为一类,非根际盐处理试验组可聚为一类,非根际对照组单独聚为一类。选择9条主要优势条带克隆测序,其中细菌类群为变形菌门、拟杆菌门、酸杆菌门和放线菌门。这些优势菌中除放线菌Candidatus属外,其他均对植物生长具有促进作用。对主要优势菌的变性梯度凝胶电泳(DGGE)图谱进行主成分(PCA)分析发现,非根际细菌与根际细菌在第一主成分上完全分离,非根际细菌均聚为一类,而根际细菌则按亲缘关系聚类。【结论】在耐盐果树滨梅正常生长时,一定程度的盐胁迫不但未能对根际土壤微生物群落造成伤害,反而起到一定的促进作用,这种促进作用体现为植株根系对有益细菌生长的保护和促进,以及对群落多样性的维持,而非根际土壤细菌的生长和群落多样性则受到了较为严重的伤害。
【Objective】 The aim of this study was to investigate the changes of rhizosphere microbial communities in salt-tolerant plants under salt stress. 【Method】 Based on the greenhouse pot experiment, the effects of NaCl (0, 2.9, 8.8 g / L) stress were studied by the methods of plant growth determination, soil physical and chemical properties, PCR-DGGE, Shannon’s diversity analysis and principal component analysis , The change and variation of bacterial diversity in rhizosphere soil and non-rhizosphere soil of salt-tolerant fruit tree Prunus mume, as well as the changes of the growth and soil physical and chemical properties of Prunus mume. 【Result】 The results showed that after 60 days of salt stress, the brightness and diversity index of 16GE-DGGE in rhizosphere soil of Rhizosphere of Plum in plum were treated with high concentration of NaCl (8.8 g / L) Degree index and richness index were the highest, the number of bands in non-rhizosphere soil was significantly decreased, the brightness of the bands was diminished, and the richness index was the lowest. Clustering analysis of DGGE bands showed that there was a high similarity (> 62%) among different bands, in which the rhizosphere salt treatment group and the rhizosphere control group could be clustered into one group, and non-rhizospheric salt treatment Groups can be grouped into one category, while non-rhG groups alone grouped together. Nine dominant bands were selected and sequenced. Among them, the bacterial groups were Proteobacteria, Bacteroidetes, Acidobacter and Actinobacteria. These dominant bacteria in addition to actinomycetes Candidatus genus, all have a role in promoting plant growth. The principal component analysis (PCA) of the denaturing gradient gel electrophoresis (DGGE) patterns of major dominant bacteria showed that non-rhizobacteria and rhizosphere bacteria were completely separated from the first principal component, non-rhizobacteria were clustered into one category, The rhizobacteria are clustered according to their relationship. 【Conclusion】 When salt-tolerant fruit Prunus mume normal growth, a certain degree of salt stress not only failed to cause damage to rhizosphere soil microbial communities, but rather played a catalytic role, which promote the growth of beneficial bacteria Conservation and promotion of species diversity, as well as the maintenance of community diversity, while the growth of non-rhizosphere soil bacteria and the diversity of communities are more seriously harmed.