摘要： 为明确不同生育时期花生根际土壤微生物群落结构变化对盐胁迫的响应，以花育25为试验材料，采用盆栽试验设置3个盐胁迫梯度处理，研究盐胁迫对花生产量的影响，通过高通量测序技术分析盐胁迫下花生开花期和收获期根际土壤微生物群落结构变化。结果表明：在不同盐胁迫处理下花生根际微生物组成基本相似，但其多样性和丰富度在开花期和收获期有明显差异。高盐胁迫下开花下针期根际细菌群落多样性和丰富度较高，而收获期土壤根际微生物种类丰富度和多样性均降低；不同胁迫处理花生根际土壤的优势菌门均为变形菌门、放线菌门、绿弯菌门、酸杆菌门、疣微菌门、拟杆菌门和Patescibacteria。盐胁迫明显提高了蓝细菌门及γ-变形菌纲、疣微菌纲、拟杆菌纲的相对丰度，尤以开花下针期明显；样本层级聚类结果显示，花生根际微生物菌群多样性差异受花生生长发育阶段和盐胁迫强度影响较大，盐胁迫处理下同一生育时期样本各聚为一类；KEGG代谢功能基因分析表明，所有处理菌群涉及碳水化合物代谢、氨基酸代谢、能量代谢、辅助因子和维生素的代谢等功能基因丰度富集，而涉及信号转导、脂质代谢、复制和修复、异种生物的生物降解和代谢、其他氨基酸的代谢、折叠分类和降解等功能的丰度较低。盐胁迫处理使涉及物质和能量代谢、膜运输、翻译复制和修复以及信号转导等优势细菌功能基因丰度增加，花生百果质量和百仁质量降低，从而降低花生产量。因此，盐胁迫对花生根际细菌群落结构的变化和花生产量影响较大，通过改良土壤微生物环境来提高花生盐胁迫耐受性，为盐碱地区发展花生生产提供理论依据。

关键词: 花生, 盐胁迫, 根际, 土壤微生物群落, 16S rRNA基因

Abstract: To assess the peanut rhizosphere bacteria community structure in response to salt stress at different development stages, the peanut variety Huayu 25 was used as experimental material, and a pot experiment was set with three salt concentrations to study the effect of salt stress on peanut yield and analyze the changes of microbial community structure of peanut rhizosphere at flowering and harvest stage under salt stress by high-throughput sequencing technology. The results showed that the rhizosphere microbial composition of peanut were basically similar under different salt stress treatments, but the diversity and richness significantly varied between flowering and harvest stage. Under higher salt stress, the diversity and richness of rhizosphere bacterial community were increased at the flowering and needling stage but decreased at the harvest stage. The dominant bacteria phyla of all soil groups were Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria, Verrucomicrobia, Bacteroidetes, and Patescibacteria. The relative abundance of Cyanobacteria, Gammaproteobacteria, Verrucomicrobiae and Bacteroides significantly increased under salt stress, especially at the flowering and needling stage. Hierarchical clustering revealed that the microbial community diversity was markedly altered by the salt concentrations and growth stages, samples of the same growth period were clustered into one group under salt stress. KEGG functional prediction analysis indicated that sequences related to carbohydrate metabolism, amino acid metabolism, energy metabolism, and metabolism of cofactors and vitamins were enriched, whereas that of signal transduction mechanisms, lipid metabolism, replication and repair, xenobiotics biodegradation and metabolism, metabolism of other amino acids, and folding, sorting and degradation were decreased. Among them, salt stress increased the abundance of functional groups involved in substance and energy metabolism, membrane transport, translation, replication and repair, and signal transduction, but decreased the 100 fruit weight and 100 kernel weight of peanut resulted in the decrease of peanut yield. Therefore, salt stress had a great impact on the peanut rhizosphere bacterial community structure and peanut yield. The salt tolerance of peanut could be enhanced by improving soil microbial environment. The results provided a theoretical basis for the development of peanut production in saline-alkali areas.

Key words: Peanut, Salt stress, Rhizosphere, Soil microbial community, 16S rRNA gene

中图分类号: 

• S565.03