Plant root diffusional barriers: genesis and implications for nutrient efficiency and stress tolerance

植物根扩散屏障：起源及其对养分效率和胁迫耐受性的影响

• 批准号: 243701334
• 负责人: Professor Dr. Mark G. M. Aarts
• 金额: --
• 依托单位: Arbeitsgruppe Molekulare Phytomedizin
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/243701334?language=en
• 关键词: Plant; root; diffusional; barriers; genesis

Casparian strips and suberin limit extracellular diffusion in plant roots by providing tight seals between adjacent cells, and between the cell wall and the plasma membrane, respectively. Such diffusional barriers are vital to enable the root endodermal cell layer to act as a selectivity barrier allowing controlled uptake of water and solutes into plants. Further, these barriers are also thought to provide a chemical or physical block to pathogen penetration into roots, including plant-parasitic nematodes accessing the vascular system for feeding. The molecular mechanisms that drive the biosynthesis of these critical barriers are poorly understood, limiting our ability to fully characterize their function and manipulate their properties for agricultural benefit. We have designed an ambitious interdisciplinary research programme integrating molecular plant science with analytical chemistry, whole plant physiology and modelling. This programme aims to deliver a complete understanding of the biology of Casparian strips and suberin, across scales, from molecules to the whole plant. Such information will enable a molecularly directed manipulation of Casparian strips and suberin, providing new pathways for the development of crop varieties with improved nutrient and water use efficiencies, and enhanced resistance to root pathogens, salinity and water stress. Such traits are essential if we are to develop crops that are more resilient to the predicted impacts of climate change on soil fertility, and to improve yields in a more sustainable manner to deliver the yield gains required to meet future population growth. By employing genomic, molecular genetic, chemical, biochemical and cell biological approaches we will discover and characterize the genes and molecular mechanisms involved in the biosynthesis of Casparian strips and suberin. Genetic resources characterized and developed through this mechanistic investigation will be leveraged to understand, at the root and whole plant level, the role of these physical and chemical barriers in mineral nutrient and water uptake, and root parasitic nematode infection. The ecological and adaptive function of these barriers to agriculturally relevant abiotic stresses such as water, mineral nutrient (deficiency and excess) and salinity will also be established. Building on this new understanding, mathematical models integrating molecular mechanistic knowledge with physiological processes at the tissue and whole plant level will also be built, providing predicative capacity to connect barrier properties with whole plant function.

凯氏带和木栓质分别通过在相邻细胞之间以及细胞壁和质膜之间提供紧密密封来限制植物根中的细胞外扩散。这样的扩散屏障对于使根内胚层细胞层能够作为选择性屏障起作用是至关重要的，所述选择性屏障允许水和溶质受控地吸收到植物中。此外，这些屏障还被认为提供了对病原体渗透到根部的化学或物理阻挡，包括植物寄生线虫进入脉管系统以进行进食。驱动这些关键屏障生物合成的分子机制知之甚少，限制了我们充分表征其功能和操纵其特性以实现农业效益的能力。我们设计了一个雄心勃勃的跨学科研究计划，将分子植物科学与分析化学，整株植物生理学和建模相结合。该计划旨在提供对凯氏带和木栓质生物学的全面了解，从分子到整个植物。这些信息将使凯氏带和木栓质的分子定向操纵成为可能，为开发具有改善的养分和水分利用效率以及增强的对根病原体、盐和水分胁迫的抗性的作物品种提供新的途径。如果我们要开发出更能适应气候变化对土壤肥力的预期影响的作物，并以更可持续的方式提高产量，以实现满足未来人口增长所需的产量增长，这些性状是必不可少的。通过采用基因组学、分子遗传学、化学、生物化学和细胞生物学方法，我们将发现和表征凯氏带和木栓素生物合成所涉及的基因和分子机制。遗传资源的特点和开发，通过这种机制的调查将被利用来了解，在根和整个植物水平上，这些物理和化学障碍的作用，在矿质营养和水分的吸收，和根寄生线虫感染。还将确定这些屏障对与农业有关的非生物压力，如水、矿物质营养（缺乏和过量）和盐度的生态和适应功能。基于这一新的认识，还将建立将分子机理知识与组织和整个植物水平的生理过程相结合的数学模型，提供将屏障特性与整个植物功能联系起来的预测能力。