花生根际土壤细菌群落对干旱和盐胁迫的响应

为明确旱、盐及旱盐双重胁迫对花生根际土壤细菌群落的影响，本研究采用盆栽试验，通过16S rRNA基 因测序技术，研究了花生开花期干旱、盐胁迫及旱盐双重胁迫下花生根际土壤细菌群落结构的变化。结果表明，花 生根际土壤细菌群落均以放线菌纲（Actinobacteria）、α-变形菌纲（Alphaproteobacteria）、未分类菌目（norank_p__Sac? charibacteria）、蓝藻纲（Cyanobacteria）、酸杆菌纲（Acidobacteria）、芽单胞菌纲（Gemmatimonadetes）和β-变形菌纲 （Betaproteobacteria）7个优势菌纲为主。干旱和盐胁迫处理均不同程度提高了α-变形菌纲和蓝藻纲的含量，且对蓝 藻纲的诱导效果较显著，推测蓝藻纲在提高花生胁迫耐受性方面具有重要功能。非生物胁迫影响根际土壤微域环 境，对花生根际土壤细菌群落结构具有调控作用。调节微生物群落结构，改良土壤微域环境，是提高植物胁迫耐受 性的有效途径。

Response of rhizosphere bacterial community structure associated with peanut (Arachis hypogaea L.) to high salinity and drought stress

To study the effect of high salinity and drought stress on bacterial community structure and diversity in peanut rhizosphere soil, pot experiment was conducted to set up the salt and drought treatment experiments in this study. The total DNA of the mature flowering rhizosphere soil was extracted and deep sequencing of V3-V4 re? gion of 16S rRNA gene was performed to characterize the bacterial community structure of drought-treated and salttreated peanuts. Taxonomic analysis showed that Actinobacteria, Alphaproteobacteria, norank_p__ Saccharibacte? ria, Cyanobacteria, Acidobacteria, Gemmatimonadetes and Betaproteobacteria were the dominant class in the pea? nut rhizosphere. Comparisons of bacterial community structure of normally-grown peanuts revealed that the relative abundance of Alphaproteobacteria and Cyanobacteria increased after stress treatments, among them Cyanobacteria was significant induced, suggesting that Cyanobacteria might have crucial implications for plant survival and stress tolerance. Many biotic and abiotic stresses altered rhizosphere soil microdomain structure and had an evident effect on the bacterial community diversity in peanut rhizosphere. Modifying microbial structure and soil microdomain en? vironment were effective ways to improve plant stress tolerance.