Nutrient impacts on plant secretions into soil

菲尔德实验室和诺克斯实验室的合作发现，植物的根和根状茎分泌高分子量的多糖(多糖)，其中一些是土壤颗粒的有效聚集物。矿物颗粒的聚集是土壤形成和土壤健康的关键因素。这些重要发现正在为出版做准备。这两个研究小组最近的工作还发现，分泌的糖链的轮廓受到营养制度的调节。目前我们知道，所有养分的缺乏都会导致土壤聚集态葡聚糖的特异性上调。这个项目将确定不同的营养制度将如何影响分泌的多糖的图谱，这些图谱是用一组具有高特异性和敏感性的单抗和碳水化合物结合模块的定量方法确定的。一个关键的目标将是确定影响多糖分泌的特定营养物质，并剖析潜在的机械生理学。该项目将涵盖陆地上的物种植物系统发育和研究从苔藓植物根状结构(一种定殖型植物，在扰动的地面上形成土壤很重要)中释放多糖，还将利用拟南芥(具有无与伦比的资源的遗传模型来剖析机械途径)和小麦(主要作物物种)。生长系统将包括固体琼脂基质(苔藓和拟南芥)和水培系统(小麦)。这是一个新颖而及时的项目，因为由于缺乏灵敏的糖分子工具，对植物根状突起和根部释放的高分子量分子的结构和功能的研究是一个严重被忽视的领域。这些工具现在可以在诺克斯实验室获得。这也是非常及时的，因为土壤结构的丧失和土壤健康状况不佳是影响作物生产力的主要全球问题。目前对植物如何影响土壤性质的分子理解还很少。

Collaborative work in the Field and Knox laboratories has discovered that plant roots and rhizoids secrete high molecular weight glycans (polysaccharides) and that some of these are potent aggregators of soil particles. Aggregation of mineral particles is a key factor in soil formation and soil health. These important discoveries are in preparation for publication. Recent work by the two groups has also discovered that the profiles of secreted glycans are modulated by nutrient regimes. Currently we know that the lack of all nutrients leads to the specific upregulation of the soil aggregating glycan. This project will determine how varying nutrient regimes will impact on profiles of secreted glycans determined using quantitative methods with sets of monoclonal antibodies and carbohydrate-binding modules with high specificities and sensitivities. A key objective will be the identification of the specific nutrients that influence the secretion of glycans and the dissection of the underlying mechanistic physiology. The project will encompass species from across the land plant phylogeny and study glycan release from bryophyte rhizoids (a colonizing class of plants, important in soil formation in disturbed ground) and also utilize arabidopsis (genetic model with unparalleled resources to dissect mechanistic pathways) and wheat (a major crop species). Growth systems will include solid agar media (for bryophytes and Arabidopsis) and hydroponic systems (wheat). This is both a novel and timely project as studies on the structure and functions of high molecular weight molecules released by plant rhizoids and roots is a severely neglected area due to the lack of sensitive glyco-molecular tools. These tools are now available in the Knox laboratory. It is also extremely timely as loss of soil structure and poor soil health are major global problems impacting on crop productivity. Current molecular understanding of how plants can influence soil properties is scant