State Key Laboratory of Crop Stress Biology for Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, China.
College of Marine Life Science, Ocean University of China, Qingdao, Shandong, China.
Appl Environ Microbiol. 2020 May 19;86(11). doi: 10.1128/AEM.02863-19.
Drought is among the most destructive abiotic stresses limiting crop growth and yield worldwide. Although most research has focused on the contribution of plant-associated microbial communities to plant growth and disease suppression, far less is known about the microbes involved in drought resistance among desert plants. In the present study, we applied 16S rRNA gene amplicon sequencing to determine the structure of rhizosphere and root endosphere microbiomes of Compared to those of the rhizosphere, endosphere microbiomes had lower diversity but contained several taxa with higher relative abundance; many of these taxa were also present in the roots of other desert plants. We isolated a strain (LTGT-11-2Z) that was prevalent in root endosphere microbiomes of and promoted drought resistance during incubation with wheat. Complete genome sequencing of LTGT-11-2Z revealed 1-aminocyclopropane-1-carboxylate deaminases, siderophore, spermidine, and colanic acid biosynthetic genes, as well as type VI secretion system (T6SS) genes, which are likely involved in biofilm formation and plant-microbe interactions. Together, these results indicate that drought-enduring plants harbor bacterial endophytes favorable to plant drought resistance, and they suggest that novel endophytic bacterial taxa and gene resources may be discovered among these desert plants. Understanding microbe-mediated plant resistance to drought is important for sustainable agriculture. We performed 16S rRNA gene amplicon sequencing and culture-dependent functional analyses of rhizosphere and root endosphere microbiomes and identified key endophytic bacterial taxa and their genes facilitating drought resistance in wheat. This study improves our understanding of plant drought resistance and provides new avenues for drought resistance improvement in crop plants under field conditions.
干旱是限制全球作物生长和产量的最具破坏性的非生物胁迫因素之一。尽管大多数研究都集中在植物相关微生物群落对植物生长和疾病抑制的贡献上,但对于沙漠植物中参与抗旱的微生物知之甚少。在本研究中,我们应用 16S rRNA 基因扩增子测序来确定比较根际和根内植物微生物组的结构。与根际相比,内植物微生物组的多样性较低,但含有一些相对丰度较高的分类群;其中许多类群也存在于其他沙漠植物的根部。我们分离出一种在比较根内植物微生物组中普遍存在的菌株(LTGT-11-2Z),该菌株在与小麦共培养时能促进抗旱性。LTGT-11-2Z 的全基因组测序揭示了 1-氨基环丙烷-1-羧酸脱氨酶、铁载体、亚精胺和科尔酸生物合成基因以及类型 VI 分泌系统(T6SS)基因,这些基因可能参与生物膜形成和植物-微生物相互作用。总之,这些结果表明耐旱植物中存在有利于植物抗旱性的细菌内生菌,并且表明在这些沙漠植物中可能发现新的内生细菌分类群和基因资源。了解微生物介导的植物抗旱性对可持续农业很重要。我们对比较的根际和根内植物微生物组进行了 16S rRNA 基因扩增子测序和培养依赖的功能分析,并确定了促进小麦抗旱性的关键内生细菌分类群及其基因。本研究提高了我们对植物抗旱性的认识,并为在田间条件下提高作物抗旱性提供了新途径。