AAFC IWYP Aligned Call Stomata signalling pathways for increasing yield potential in wheat

谷物为世界提供食物，约占全球热量摄入的一半。世界粮食库存是衡量粮食安全的最基本指标。粮食消费每年都在增加，生物燃料生产的最终用途也在增加，同时可用的农业用地无法满足这些不断增长的需求。世界范围内对粮食日益增长的需求要求更高的产量和更高的产量潜力。预计到2050年，仅粮食产量就必须增加一倍，才能满足人口的需求。气候变化的进一步影响威胁到产量的稳定性，从而使这一挑战复杂化。加拿大是全球五大小麦出口国之一，小麦是加拿大最大的经济作物，年产值超过50亿美元，但炎热和干旱对加拿大大草原的影响越来越频繁，这对世界上许多小麦出口国来说也是一个严重的问题，包括澳大利亚和美国。在我们不断变化的世界中，气孔是提高小麦产量的有吸引力的目标。首先，它们是光合作用的关键决定因素，通过二氧化碳吸收调节碳捕获，光合作用是提高产量潜力的速率限制步骤。其次，气孔是蒸腾作用的关键结构特征。这意味着它们是WUE的主要参与者，但也通过蒸发冷却保持最佳叶片温度。小麦在开花期和灌浆期对温度敏感，因此叶片温度的维持对小麦至关重要。此外，蒸腾对维持冠层温度的降温作用也与水分利用效率有关。气孔导度与小麦籽粒产量直接相关，这是由于光合作用CO2扩散增加和蒸发冷却增加。虽然通常在水分利用效率和产量之间存在权衡，但优化气孔模式和增加气孔对环境线索的响应可以导致这两个方面的改善。在这个项目中，我们将在小麦中产生和筛选气孔模式改变（气孔指数增加或减少）和气孔行为改变的基因突变体，以获得更好的产量潜力、水分利用效率和叶片/冠层温度控制。在加拿大、英国和澳大利亚，将提供在不同田间环境下表现出最佳产量潜力的基因编辑/耕作品系，以便将非转基因突变体快速纳入小麦育种计划。温室和田间环境的表型分析将伴随着分子分析，以确定气孔通路的上游/下游元素，以微调我们的方法，以获得更高的产量潜力和稳定性。在小麦中，调节气孔通路的关键等位基因将被确定，这是通过优化呼吸、碳同化和蒸腾提高产量的种质和标记开发的重要第一步。这项工作属于“与国际合作伙伴、上游性状发现、性状开发和基础科学合作，目标是在未来20年内将小麦的遗传产量潜力提高50%”的优先事项，因为它汇集了国际专业知识和努力，利用发现和基础科学来研究产量潜力的遗传组成部分。结合在性状和种质开发方面的强大应用元素，这将为加拿大和全球的小麦生产者带来快速的成果。

Cereals feed the world, representing roughly half of the global caloric intake. World grain stocks are the most basic measure of food security. Grain consumption is increasing annually, and end-use for biofuel production is also on the rise, meanwhile the available agricultural land cannot accommodate these growing needs. The increasing demand for grain worldwide necessitates higher production, and higher yield potential. It is anticipated that doubling of grain yields for food production alone will be necessary to meet population demands by the year 2050.Further impacts of climate change confound this challenge by threatening yield stability. Canada is one of the top five global exporters of wheat, which is the largest Canadian cash crop with an annual value exceeding $5 billion, but the impacts of heat and drought have been observed with increasing frequency on the Canadian Prairies,and has also been a serious problem for many wheat exporters around the world, including Australia and the United States. Stomata are attractive targets to improve wheat yield in our changing world. First, they are key determinants of photosynthesis that regulate carbon capture through CO2 uptake, and photosynthesis is a rate limiting step to improving yield potential. Second, stomata are key structural features in transpiration. This means they are major players in WUE, but also in maintaining optimal leaf temperatures through evaporative cooling. Maintenance of leaf temperature is critical for wheat, due to its temperature sensitivity during anthesis and grain filling. Additionally, the cooling effect of transpiration in maintaining canopy temperature has also been implicated in WUE. Stomatal conductance has been directly linked with wheat grain yield,due to both increased CO2 diffusion for photosynthesis and increased evaporative cooling. While often there is a trade off between WUE and yield, optimizing stomatal patterning and increasing stomatal response to environmental cues can lead to improvements on both fronts. In this project, we will generate and screen genetic mutants in wheat with altered stomatal patterning (increased or decreased stomatal index) and altered stomatal behaviour for better yield potential, WUE and leaf/canopy temperature control. Gene-edited/TILLING lines showing the best yield potential in different field settings will be made available for rapid incorporation of non-GM mutants into wheat breeding programs in Canada, the UK and Australia. Phenotypic analyses from both greenhouse and field environments will be accompanied with molecular analyses to identify upstream/downstream elements of stomatal pathways to fine-tune our approach for higher yield potential and stability. Key alleles regulating stomatal pathways will be identified in wheat, a first important step in germplasm and marker development for improve yields through optimized respiration, carbon assimilation and transpiration. This work falls within the call priorities 'In collaboration with international partners, upstream trait discovery, trait development and fundamental science with the goal of increasing the genetic yield potential in wheat by 50% in the next 20 years', as it brings together international expertise and efforts to employ discovery and fundamental science to study genetic components of yield potential, combined with a strong applied element on trait and germplasm development which will bring rapid results for wheat producers in Canada and around the globe.