Exploiting the potential of genotype microbiome interactions to promote sustainable soil health in southern Africa

背景玉米是南部非洲最重要的谷类作物，但是在干旱日益发生和严重以及土壤养分利用率低的情况下，如果没有新的管理措施，预计已经很低的产量将进一步下降。制定确保粮食安全和帮助减轻小农贫困的新办法至关重要。培育耐旱性更强、吸收氮能力更强的玉米新品种，有望改变这些种植制度，但首先我们需要了解这些作物如何与土壤、土壤中的微生物以及管理相互作用，从而为作物生产带来好处，这将有助于确保粮食安全。我们的研究旨在解决考虑作物基因组成（基因型）、土壤微生物及其过程之间相互作用的性质是否为未来的玉米育种计划提供了一种可行的方法，以帮助确保南部非洲的产量稳定性和对低养分可用性和干旱的适应能力。我们将首先在受控的环境条件下，对CIMMYT种质收集的各种玉米基因型进行详细筛选，以确定其对土壤氮和碳过程的影响程度。该筛选将包括CIMMYT鉴定的耐低土壤氮或干旱胁迫条件的品种。从这个屏幕上，我们将选择更详细地研究，并研究它们如何塑造进行这些过程的微生物种群，并了解支撑可持续生产和土壤健康的植物-土壤相互作用。然后，我们将选择六个玉米品系来建立相互作用的一致性，这些相互作用是在受控环境下建立的，在津巴布韦CIMMYT农民网络的田间条件下建立的。了解这些相互作用将告诉我们是否有可能使用不同的玉米基因型来影响土壤微生物群落，或未来培育特定特征，以促进更有效的氮利用，并赋予更大的抗旱能力。潜在的应用和效益证明玉米的变异对土壤微生物群和过程的影响是制定利用这些性状并结合可持续管理实践提高作物产量战略的重要一步。我们预计，这一基金会奖励将在未来引领一个框架的发展，为南部非洲未来的玉米育种倡议或品种选择提供信息，这是基于作物在可持续养分获取方面增强和利用土壤健康的能力，从而帮助确保更可靠的产量和更大的适应不断变化的环境条件的能力。

ContextMaize is the most important cereal crop in southern Africa but without new management practices in the face of increasing occurrence and severity of drought and low soil nutrient availability, yields which are already low are predicted to further decline. It is critical that new approaches are developed to ensure food security, and help alleviate poverty of smallholder farmers. Breeding for new maize cultivars with greater tolerance to drought and enhanced ability to take up nitrogen holds much promise to transform these cropping systems, but first we need to understand how these crop plants interact with the soil, the microorganisms in the soil, and with management to confer benefits for crop production, that will help ensure food security. Aims and objectivesOur research aims to address whether considering the nature of interactions between crop genetic make-up (genotype), soil microorganisms and the processes they undertake provides a viable approach for future maize breeding programmes to help ensure yield stability and resilience to low nutrient availability and drought in southern Africa. We will firstly undertake, under controlled environment conditions, a detailed screening of a wide range of maize genotypes from the CIMMYT germplasm collection to establish the extent of variation in influence on soil nitrogen and carbon processes. This screen will include varieties characterised by CIMMYT as being tolerant of low soil nitrogen or drought stress conditions. From this screen we will select lines to examine in more detail, and look at how they shape the microbial populations that undertake these processes, and gain understanding of plant-soil interactions underpinning sustainable production and soil health. We will then select six maize lines to establish consistency of interactions, established in controlled environments, under field conditions across CIMMYT farmer's network in Zimbabwe. Understanding these interactions will tell us if there is potential in using different maize genotypes to influence the soil microbial community, or future breeding for particular characteristics, to promote more effective nitrogen use and to confer greater resilience to drought. Potential applications and benefitsDemonstrating variation of maize for impacts on soil microbiota and processes is an essential step to developing strategies to exploit these traits for enhancing crop yields in combination with sustainable management practices. We anticipate that this foundation award will lead in the future to the development of a framework to inform future maize breeding initiatives or cultivar selection for southern Africa, that is based on the ability of crops to enhance and capitalise on soil health in terms of sustainable nutrient acquisition thereby helping ensure more reliable yields and greater resilience to changing environmental conditions.