Unlocking the genetic potential of the root system, rhizosheath mucilage and microbiome of wheat (Triticum aestivum L.)

释放小麦 (Triticum aestivum L.) 根系、根鞘粘液和微生物组的遗传潜力

基本信息

批准号：
1804473
负责人：
金额：
--
依托单位：
University of Cambridge
依托单位国家：
英国
项目类别：
Studentship
财政年份：
2016
资助国家：
英国
起止时间：
2016 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=studentship-1804473
关键词：
Unlocking genetic potential root system

项目摘要

An increasing global population, projections of climates that will challenge sufficient crop production, and a detrimental use of fertiliser and pesticides mean that we need to increase the productivity of land currently under cultivation with minimal impact on the environment. Wheat is the second largest contributor to global crop production and is cultivated across a range of latitudes across both hemispheres. The wheat root system is a crucial determinant of plant performance, yet roots are overlooked in breeding due to the challenge of studying organs below ground. Evidence from the literature indicate that water and nutrient uptake are often suboptimal in high yielding and stressed environments. Facilitating the incorporation of root system characteristics into breeding programmes and developing crop management strategies that enhance root function could be key to increasing yield potential and stability, while minimising inputs. To fill the knowledge gap on root-rhizosphere-yield interactions the research presented here falls into three strategic areas: root system architecture (RSA), root secretions and the rhizosphere microbiome.1) Genetic mapping of RSA in the Avalon x Cadenza Doubled Haploid (AxC) mapping population identified quantitative trait loci (QTL) for seedling seminal root angle, length and growth rate. Replicable QTLs were associated with root angle and mapped to chromosomes 3A and 4D, explaining 7% of phenotypic variation. After extensive root phenotyping, the tails displaying phenotypes at the extremes of the population distribution were taken forward for field trials. Correlations between seedling root phenotypes and the root and canopy phenotypes of mature plants grown in the field were calculated.2) Root secretions represent a significant loss of fixed carbon from the plant, yet they are thought to confer benefits in relation to plant water status, nutrition, salinity stress, microbial interactions and the development of the rhizosheath. Enzyme-linked immunosorbent assays (ELISAs) were used to quantify the amount of high molecular weight polysaccharides in the rhizosheath of AxC tails, determine the influence of genotype on secretion and investigate potential interactions with RSA.3) A metagenomics study of the microbial population within the rhizosheath of AxC tails uncovered differences in microbial community composition between lines of the same species. Lines grouped according to phenotype (level of secretion, RSA, yield) showed that the microbiome of high-yielding lines differed from that of low-yielding lines. The level of secreted polysaccharides was associated with differences in the microbiome.Overall, this research presents a novel, multi-faceted study of the root system, from seedling to mature plant in the field, as a holistic approach to crop improvement is more robust than the unlikely discovery of a "silver bullet".

越来越多的全球人口，将挑战足够农作物生产的气候预测以及对肥料和农药的有害使用意味着我们需要提高目前正在耕种的土地生产率，对环境的影响最小。小麦是全球作物产量的第二大贡献者，并且在两个半球的一系列纬度地区都耕种。小麦根系是植物性能的关键决定因素，但由于在地下研究器官的挑战而忽略了育种的根。文献中的证据表明，在高产和压力环境中，水和养分吸收通常是次优的。促进将根系特征纳入育种计划中，并制定提高根部功能的作物管理策略，这可能是提高产量潜力和稳定性的关键，同时最大程度地减少投入。为了填补根部 - 磷酸晶相互作用的知识差距，此处提供的研究属于三个战略领域：根系架构（RSA），根部分泌和根际微生物组。1）Avalon X Cadenza X Cadenza中RSA的遗传学映射量及确定的数量特质（QT）的量化量（QT），QT-eftrit and Sylation（Q.T）的成长率（qt and）的种子（qt and and syper）（qt and）。可复制的QTL与根角有关，并映射到染色体3A和4D，解释了7％的表型变异。经过广泛的根表型，将在人口分布的极端表现出表型的尾部进行了野外试验。计算了植物中生长的成熟植物的幼苗根表型与根和冠层表型之间的相关性。2）2）根部分泌物是植物中固定碳的显着损失，但是它们被认为可以赋予与植物水状态，营养，盐度应激，微生物相互作用以及rhizosheath的发展相关的益处。使用酶联免疫吸附测定法（ELISA）来量化AXC尾巴根部中高分子重量多糖的高分子量多糖的量，确定基因型对分泌的影响，并研究与RSA的分泌相互作用。根据表型分组的线（分泌水平，RSA，产率）表明，高收益线的微生物组与低收益线的微生物组不同。分泌的多糖水平与微生物组的差异有关。术语，这项研究提出了一项针对根系的新型，多方面的研究，从该领域的幼苗到成熟的植物，作为农作物改善的整体方法比不太可能发现的“银弹”更强大。