Fructan biology in cereal grains and its impact on grain morphology, yield, composition, and plant performance

果聚糖是植物界中最重要的水溶性多糖之一。尽管果聚糖含量与碳水化合物的分配和储存以及对各种非生物胁迫的保护有着普遍的关系，但谷类作物中果聚糖生物学的遗传和分子背景研究很少。MA 4814/3-1项目旨在解决谷物中的果聚糖生物学及其对谷物形态、产量、成分和植株表现的影响。这项工作是在阿德莱德的ARC植物能源生物学卓越中心(COE)进行的，并在相关合作伙伴的帮助下进行。一组具有遗传特征的两行春大麦品系被调查了果聚糖模式的扰动。全基因组关联分析能够剖析与观察到的变异性相关的新基因(任务1)。为了改进今后相关品系的筛选和育种过程，获得了上述品系成熟籽粒的光谱数据。目前正在评估表示特定果聚糖模式的光谱特征，并将其用于开发果聚糖传感器(任务2)。大麦品系果聚糖模式中检测到的扰动也与籽粒形态、产量和成分的信息以及植物的逆境耐受值相关。在受控条件下，用选定的品系子集进行了综合干旱胁迫试验。相关分析将允许在短时间内发现重要的关联(任务3)。亚细胞定位研究建立在前人工作的基础上，证明果聚糖整合到膜上，这可能与膜稳定和对活性氧的解毒有关。确定了两种具有特殊特异性的抗体，目前正在测试它们在免疫组织学实验中的适用性。此外，大麦淀粉和β-葡聚糖突变体的果聚糖图案和颗粒形态也发生了变化，这是获得有关谷物中碳分配调节的更多信息的宝贵材料(任务4)。申请延长一年的拨款将能够：a)通过表达数据验证检测到的新的遗传-分子关系，b)最终确定果聚糖传感器的开发，c)完成由澳大利亚拨款支持的胁迫实验，以及d)对选定的大麦品系进行免疫组织学分析。这一额外一年计划的工作将使有价值的成果得以高质量地发表，从而支持申请者的载体开发机会。所获得的知识和技术将在返回阶段(任务5)转移到Julius Kühn研究所(JKI)联邦栽培植物研究中心、奎德林堡抗逆性研究所的耐寒小麦品系小组。

Fructans represent one of the most important groups of water–soluble polysaccharides in the plant kingdom. Despite the general relation of fructan content to carbohydrate partitioning and storage as well as to the protection against various abiotic stresses, the genetic and molecular context of fructan biology in cereal grains has been investigated sparsely. The project MA 4814/3-1 aims at resolving fructan biology in cereal grains and its impact on grain morphology, yield, composition, and plant performance. The work is performed at the ARC Centre of Excellence (CoE) in Plant Energy Biology, Adelaide (host) and with the help of associated partners.A panel of genetically profiled two row Spring barley lines has been investigated for perturbations in fructan patterns. Genome wide association analysis enabled to dissect new genes related to the observed variability (Task 1). To improve future screening of relevant lines and breeding processes spectral data from mature grain of aforementioned lines were acquired. Spectral signatures indicative for particular fructan patterns are currently evaluated and used for the development of a fructan sensor (Task 2). Detected perturbations in fructan patterns of the barley lines are also correlated with information on grain morphology, yield and composition as well as with plant stress tolerance values. A comprehensive drought stress experiment has been performed under controlled conditions with a selected subset of lines. Correlation analysis will allow detecting significant associations shortly (Task 3). Subcellular localization studies build on previous work to prove fructan integration into membranes, which is possibly related to membrane stabilization and detoxification of reactive oxygen species. Two antibodies with particular specificity were identified and are currently tested for their applicability in immunohistological experiments. Also, barley starch and beta-glucan mutants with altered fructan patterns and grain morphology were identified, representing valuable material to gain additional information about the regulation of carbon partitioning in cereals (Task 4). The applied grant prolongation for one year will enable to: a) validate the detected new genetic-molecular relations by expression data, b) to finalise the fructan sensor development, c) to complete the stress experiments supported by an Australian grant, and d) to perform the immunohistological analysis of selected barley lines. Together, the work planned in this additional year will allow for the high quality publication of the valuable results and thus supporting the carrier development chances of the applicant.The gained knowledge and technologies will be transferred to a panel of frost tolerant wheat lines at the Julius Kühn-Institut (JKI) Federal Research Centre for Cultivated Plants, Institute for Resistance Research and Stress Tolerance, Quedlinburg, in the returning phase (Task 5).