Characterization of radicle root hair functions adding to a vigorous seedling establishment under adverse nutrient and water seedbed conditions

胚根根毛功能的表征有助于在不利的营养和水分苗床条件下促进幼苗的旺盛生长

• 批准号: 403625794
• 负责人: Professor Dr. Gerd Patrick Bienert
• 金额: --
• 依托单位: Lehrstuhl für Crop Physiology
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/403625794?language=en
• 关键词: Characterization; radicle; root; hair; functions

Germination constitutes a very critical growth phase during crop development. A vigorous seedling establishment in this stage will decide over the overall plant performance, stress resistance and yield formation. A vigorous seedling establishment highly depends on a sophisticated not yet understood rhizosphere organization ensuring water and nutrient uptake as well as soil anchorage. Shortly after the embryonic root penetrates the coleorhiza and is entering the soil environment, the radicle is characteristically coated in a bloomy manner by numerous root hairs. Surprisingly, their biological role is yet scarcely understood. We hypothesize that radicle root hairs represent major drivers for water and nutrient uptake, particularly under adverse nutrient and water seedbed conditions, and trigger seedling-establishment-efficiency in suboptimal agricultural sites.Thus, the main goal of this PP2089 project is to identify and characterize the role of maize root hair properties in rhizosphere organizational processes, ensuring maize seedling establishment under single or combined water and/or nutrient [B & P] deficit and as a function of soil texture and compaction, in line with the overall PP2089 objectives.During germination, very defined interlinked feedback loops between nutrient and water availability, exudation processes, microbes and soil properties exist. Capturing this dynamic plasticity in its full “entirety” is experimentally feasible when focusing on radicles. To achieve our aims, growth rates, shoot biomass increase, micro- and macronutrient uptake, apoplastic barrier traits, root system architecture development and root hair characteristics will be quantified in maize wild type and mutant plants lacking proper root hairs. Data will be collected in soil column time-series experiments exploiting plants germinating under optimal or adverse water and/or B or P-limiting seedbed conditions also differing in their texture and compaction.Complementary, water and nutrient transporter gene expression and protein localization patterns will be determined to unravel the mutual impact of water uptake on nutrient uptake and vice versa, also at the molecular level. RNA-sequencing of root hair versus radicle transcriptomes are targeted to identify signalling pathways as well as gene expression patterns and networks driving, soil property-dependent, the responses to water and/or P availability, advancing our understanding on rhizosphere processes which are allowing plants to adapt to adverse seedbed conditions.XR-CT scanning will visually revoke the impact of root hairs on 3D root growth development and appearance to complete the picture.In summary, this project will unravel the causative interplay between molecular and morphological root hair traits, soil characteristics and water and nutrient availability in the rhizosphere and therewith the role of root hairs in ensuring the hydromineral nutrition of seedlings during germination in adverse seedbeds.

发芽是作物发育过程中一个非常关键的生长阶段。在此阶段建立一个旺盛的幼苗将决定整个植物的表现，抗逆性和产量形成。一个充满活力的幼苗建立高度依赖于一个复杂的尚未了解的根际组织，确保水和养分的吸收以及土壤锚定。胚根进入土壤环境后不久，胚根被许多根毛以开花的方式包裹。令人惊讶的是，它们的生物学作用还很少被理解。我们假设胚根根毛是水分和养分吸收的主要驱动力，特别是在不利的养分和水分苗床条件下，并在次优农业地点触发幼苗建立效率。因此，本PP 2089项目的主要目标是确定和表征玉米根毛特性在根际组织过程中的作用，确保玉米幼苗在单一或组合的水分和/或养分[B & P]不足的情况下，根据PP 2089的总体目标，作为土壤质地和压实度的函数建立。在发芽期间，养分和水分可用性之间非常明确的相互关联的反馈回路，存在渗出过程、微生物和土壤性质。捕捉这种动态可塑性在其完整的“整体”是实验可行的，当专注于胚根。为了实现我们的目标，将在玉米野生型和缺乏适当根毛的突变体植物中量化生长速率、芽生物量增加、微量和大量营养素吸收、质外体屏障性状、根系结构发育和根毛特征。数据将收集在土柱时间序列实验利用植物发芽下的最佳或不利的水和/或B或P-限制苗床条件下也不同的质地和compactment.Complementary，水和养分转运基因表达和蛋白定位模式将被确定，以解开相互影响的水分吸收养分吸收，反之亦然，也在分子水平上。根毛与胚根转录组的RNA测序的目标是确定信号传导途径以及基因表达模式和网络驱动，土壤性质依赖，对水和/或磷的可用性，促进我们对根际过程的理解，这是允许植物适应不利的苗床条件。XR-CT扫描将直观地撤销根毛对3D根系生长发育和外观的影响，以完成图片。总之，该项目将揭示分子和形态根毛性状之间的因果关系，土壤特性和根际的水和养分有效性，以及根毛在确保不利苗床中发芽期间幼苗的水矿物营养方面的作用。