Dynamic acclimation of source capacity in fluctuating light and temperature environments

在波动的光和温度环境中动态适应光源容量

• 批准号: 518863370
• 负责人: Professor Dr. Tsu-Wei Chen
• 金额: --
• 依托单位: Albrecht Daniel Thaer-Institut für Agrar- und Gartenbauwissenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/518863370?language=en
• 关键词: Dynamic; acclimation; source; capacity; fluctuating

Wheat is one of the most important staple food crops and high grain yields are essential for global food security. Breeding raised yields continuously over the past century, however yield potential is increasingly suppressed by challenges associated with climate change and regulatory restrictions on crop inputs. Our extensive previous work confirmed that limitations to wheat yield potential are primarily determined by traits implicated in source-sink relations. The aim of this subproject in the Package Proposal “Wheat source-sink relationships and limitations (WheatSouSi)” is to understand the effects of environmental fluctuations on the formation, acclimation and limitation of canopy source capacity.Plants constantly acclimatize their photosynthetic capacity to fluctuating light and temperature environments. Acclimations are dynamic physiological processes affecting the size and the capacity of photosynthetic organs, which determine source capacity of winter wheat for grain filling. Although light and temperature acclimation of photosynthesis have been well studied using constant light and temperature environments, our knowledge about the acclimation to fluctuating light and temperature conditions is rare. Based on the hypothesis that synthesis rates of photosynthetic proteins depend non-linearly on light and temperature, we first propose a mechanistic model of photosynthetic protein turnover to describe the acclimation to fluctuating light and temperature. Second, a series of growth chamber experiments are planned to parameterize and to validate the proposed model in 50 winter wheat cultivars. The differences in photosynthetic acclimation strategies between cultivars can be characterized by their parameters in the model. Additionally, the combined effects of light and temperature on the coordination between stomatal morphology, photosynthetic induction and water use efficiency at leaf level will be quantified and integrated into static and dynamic functional-structural plant models (FSPMs) to understand how canopy source capacity can be maximized by photosynthetic acclimation strategies. To synthesize the outcomes of all results, structural equation modelling will be used to systematically test the strength and significance of causal interdependencies between physiological traits, source strength, sink strength and grain yield. The knowledge gain will facilitate a better understanding of crop physiology and improve crop models describing source and sink dynamics.

小麦是最重要的主食作物之一，粮食高产对全球粮食安全至关重要。在过去的世纪里，育种不断提高产量，但产量潜力越来越受到气候变化和作物投入监管限制相关挑战的抑制。我们以前的大量工作证实，小麦产量潜力的限制主要是由源库关系中涉及的性状决定的。小麦源库关系与限制（WheatSouSi）子项目的目的是了解环境波动对冠层源容量形成、适应和限制的影响。植物不断适应其光合能力以适应波动的光和温度环境。驯化是影响冬小麦光合器官大小和光合能力的动态生理过程，决定着冬小麦籽粒灌浆的源容量。虽然光合作用的光和温度驯化已经很好地研究了使用恒定的光和温度环境，我们的知识，驯化波动的光和温度条件是罕见的。基于光合蛋白合成速率与光温非线性相关的假设，本文首先提出了一个光合蛋白周转的机理模型来描述植物对光温变化的适应。其次，通过一系列的生长室试验，以50个冬小麦品种为例，对模型进行了参数化和验证。品种间光合适应策略的差异可以通过模型中的参数来表征。此外，光和温度对气孔形态，光合诱导和水分利用效率之间的协调在叶片水平的综合影响将被量化，并集成到静态和动态功能结构植物模型（FSPM），以了解冠层源容量可以最大化的光合适应策略。为了综合所有结果的结果，将使用结构方程模型来系统地测试生理性状、源强度、库强度和谷物产量之间因果关系的强度和意义。知识的获得将有助于更好地了解作物生理学，并改善描述源和库动态的作物模型。