不同耐旱型甘蔗根系构型对根际微生物群落的作用机理

Drought stress is one of the natural disasters that seriously restrict agricultural production. Spatial distribution of root configuration and its interaction with rhizosphere soil microorganisms is important factors for alleviating root drought stress and improving crop drought tolerance. In this study the sugarcane roots - microorganisms as the core, by in-situ collection drought tolerant and sensitive to the sugarcane roots, clear type different drought resistance of sugarcane root system configuration under drought stress variation characteristics, through the determination of root secretion, clear different drought-tolerant type of sugarcane root system configuration by secreted metabolite affects the process of rhizosphere microenvironment, and associated rhizosphere microbe, proven different drought-tolerant type sugarcane roots secretion metabolites affected rhizosphere microorganisms constitute the process of action. The purpose of this study was to synthesize root configuration, root secretion and rhizosphere microorganism, and further reveal the mechanism of different drought-tolerant root configurations affecting rhizosphere microbe through root secretion, so as to provide theoretical basis for scientific breeding and promotion of drought-tolerant sugarcane varieties.

干旱胁迫是严重制约农业生产的自然灾害之一。根系构型空间分布及其与根际土壤微生物互作是缓解根系干旱胁迫和提高作物耐旱能力的重要因素。本研究以甘蔗根系-微生物为核心，通过原位采集耐旱型和敏感型甘蔗根系，明确干旱胁迫下不同耐旱型甘蔗根系构型的变化特征，通过测定根系分泌物，明晰不同耐旱型甘蔗根系构型通过分泌代谢物影响根际微环境的作用过程，同时关联根际微生物群落，探明不同耐旱型甘蔗根系分泌代谢物影响根际微生物种群构成的作用过程。本研究将根系构型、根系分泌物和根际微生物三者相结合，进一步揭示不同耐旱型根系构型通过根系分泌物影响根际微生物群落的作用机理，为科学选育和推广耐旱型甘蔗品种提供理论依据。

甘蔗是重要的糖料和能源作物，其产量受干旱胁迫影响较大。根系构型空间分布及其与根际土壤微生物互作是缓解根系干旱胁迫和提高甘蔗耐旱能力的重要因素。本研究以甘蔗根系-微生物为核心，通过原位采集耐旱型和敏感型甘蔗根系，发现耐旱型甘蔗根际细菌群落在水分充足条件下抗旱细菌丰度较高，而敏感型甘蔗仅在干旱胁迫下积累抗旱细菌，干旱胁迫下根际细菌丰度的变化主要集中在根瘤菌门和链霉菌门。这种变化与干旱胁迫下寄主植物的生理状态、土壤有效磷、土壤脲酶和土壤酸性蛋白酶直接相关。为了进一步研究植物促生根际细菌（PGPR）是如何缓解干旱胁迫对植物的影响，我们通过meta分析的方法，发现不同类群的PGPR在对植物表型特征、光合作用和抗氧化酶活性具有不同程度的调控作用，进而帮助植物抵御水分亏缺。本研究将根系构型、根系分泌物和根际微生物三者相结合，进一步揭示不同耐旱型根系构型通过根系分泌物影响根际微生物群落的作用机理，为科学选育和推广耐旱型甘蔗品种提供理论依据。相关研究成果发表于Plant, Cell & Environment和Frontiers in Microbiology期刊。. .