Bilateral BBSRC - Embrapa. Exploitation of the rhizosphere microbiome for sustainable wheat production

目前的模型预测，到2050年世界人口将达到90亿，农作物产量需要增加70-100%才能维持人口增长。小麦是英国产量最高的谷物，其平均产量高于世界平均水平。然而，人们担心小麦产量的增长速度现在已经停滞。相比之下，巴西目前是一个小麦净进口国，但最近的举措，包括在热带草原地区（塞拉多）种植小麦，旨在提高产量和生产力，使巴西在小麦生产方面初步实现自给自足，并最终成为这种全球重要作物的出口国。因此，开发改良和先进的可持续小麦生产方法是两国的优先研究领域，Embrapa和BBSRC之间的联合小麦研究项目证明了这一点。目前依赖于不可持续水平的无机肥料、农药和其他化学投入的集约化农业做法对环境造成破坏，是不可持续的——显然，扩大这些农业做法以满足未来需求在经济上或环境上都是不可行的，因此我们迫切需要探索其他选择，以应对全球粮食安全挑战。植物被数量惊人的微生物定植，这些微生物的细胞密度比植物细胞的数量大得多。最近的研究发现，土壤微生物在许多方面有益于作物，包括改善植物营养状况和抑制疾病。然而，人们对这些群落的确切性质和所需的微生物伙伴知之甚少，更不用说它们对宿主植物有益的机制了。因此，确定土壤微生物群落如何影响小麦植株健康以实现可持续集约化生产是很重要的。确定与植物，特别是根系（根际）相关的土壤微生物群的最佳组成，为可持续土壤管理战略提供信息，这是一种新的独特策略，可以促进植物生长和健康，这是以前从未尝试过的。根际微生物群可以提供一系列维持植物发育的功能，如：固氮、营养物溶解或防御病原体。然而，微生物和植物之间有益相互作用的机制尚未得到很好的阐明。了解这些机制将是开发可持续小麦生产的根际微生物群的关键，也是本提案中计划的工作的核心。在这个项目中，我们将阐明寄主植物（包括现代小麦和祖先小麦）在基因型和根系化学方面的相对重要性，以及作物轮作和施肥制度等耕作方式，在形成小麦根际微生物群方面。微生物组将使用元基因组和元转录组技术进行评估；而植物寄主基因型将通过多样性阵列技术和植物根化学代谢组学来确定。我们还将通过“原理验证”实验确定根际微生物组的关键成员，以评估微生物组结构的操纵如何影响植物的性能。因此，我们将全面了解影响微生物组结构的因素，以及微生物组如何影响作物健康和产量——这两个都是优化微生物组功能以可持续方式提高植物产量所必需的。

Current models predict that the world's population will reach 9 billion by 2050 and that crop yields will need to increase by 70-100% to sustain the population growth. Wheat is the UK's most highly grown cereal, with high average yields in comparison with the world average. However, there are concerns that rates of wheat yield increases have now stalled. In contrast, Brazil is currently a net wheat importer, but recent initiatives, including the cultivation of wheat in tropical savannah areas (the Cerrado), aim to increase production and productivity so that Brazil will initially become self-sufficient in wheat production and eventually an exporter of this globally important crop. Developing improved and advanced sustainable wheat production methods, therefore, is a priority research area for both countries, as evidenced by the joint wheat research programme between Embrapa and BBSRC.Current intensive agricultural practices that depend on unsustainable levels of inorganic fertilisers, pesticides and other chemical inputs are environmentally damaging and unsustainable - it is clear that expansion of these agricultural practices to meet future needs is not economically or environmentally feasible and so we urgently need to explore other options to meet the global food security challenge. Plants are colonized by an astounding number of microorganisms that can reach cell densities much greater than the number of plant cells. Recent research has found that soil microbes benefit crop plants in a number of ways, including improved plant nutritional status and disease suppression. However, the exact nature of these communities and the microbial partners required are poorly understood, let alone the mechanisms by which they benefit host plants. As such, it is important that we determine how the soil microbial community influences wheat plant health to achieve sustainable intensification of production.Determining the optimum composition of soil microbiomes associated with plants, especially the root systems (the rhizosphere), to inform sustainable soil management strategies represents a novel and unique strategy to boost plant growth and health that has not previously been attempted. The rhizosphere microbiome can provide a range of functions to sustain plant development such as: nitrogen fixation, nutrient solubilisation or defence against pathogens. However, elucidation of the mechanisms underlying beneficial interactions between microbes and plants are not well understood. Understanding these mechanisms will be key to developing the rhizosphere microbiome for sustainable wheat production, and is central to the work planned in this proposal.In this project, we will elucidate the relative importance of the host plant (both modern and ancestral wheat) in terms of genotype and root chemistry, as well as farming practices such as crop rotation and fertilisation regime, in shaping the wheat rhizosphere microbiome. The microbiome will be assessed using meta-genomic and meta-transcriptomic techniques; whereas the plant host genotype will be determined using diversity arrays technology and plant root chemistry through metabolomics. We will also identify keystone members of the rhizosphere microbiome through 'proof of principle' experiments to assess how manipulation of the microbiome structure influences plant performance. As such, we will obtain a holistic understanding of the factors influencing the microbiome structure, as well as how the microbiome influences both crop health and yield - both of which are required to optimise microbiome function for enhanced plant production in a sustainable manner.