权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Genetic and mechanical approaches to enhancing crop seed vigour

增强作物种子活力的遗传和机械方法

基本信息

批准号：
BB/N009754/1
负责人：
George Bassel
金额：
$ 54.57万
依托单位：
University of Birmingham
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2016
资助国家：
英国
起止时间：
2016 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FN009754%2F1
关键词：
Genetic mechanical approaches enhancing crop

项目摘要

Seeds are the start and end point for the vast majority of human agriculture. The annual global seed trade is currently valued at over £34 billion, and the production and sale of high quality seeds which germinate uniformly and rapidly underpin this industry. Seeds experience a range of stresses in the field prior to crop establishment. These include low water stress and mechanical impedance from compact soils. Seed vigour refers to the ability of seed to germinate and establish seedlings across a wide range of environmental conditions, and defines the success of crop establishment in the field. This is a key determinant of yield as the absence of a plant leads to no end product to harvest. Improving this trait in crops is a primary goal of the agricultural industry, however the underlying mechanisms of vigour remain poorly understood.The growth of plant cells is a mechanical process driven by internal turgor pressure pushing against the surrounding cell wall. Cells get bigger when the surrounding cell wall is weakened and yields in response to internal turgor. Genes which encode proteins that are secreted to the cell wall and modify its structural composition and strength have been identified. Once such protein is named expansin, and acts to loosen cell wall structures, permitting cell growth.The seed to seedling transition is driven exclusively through cell expansion in the absence of cell divisions. The ability to generate of mechanical force sufficient to counteract external stresses defines the ability of a seedling to establish across a wide range of environmental conditions, and hence be vigorous. Increasing the expression of expansin enables seedling establishment under stress conditions which normally limit this process. Seed vigour may therefore be considered a mechanically driven agronomic trait and the control of expansin expression a target. This project takes an interdisciplinary approach to uncover the genetic factors and mechanical basis of the seed to seedling transition, and seed vigour. We previously identified proteins which represent high confidence candidate regulators of expansin gene expression. Increasing expansin gene expression can increase seed vigour making these genetic targets to enhance seed vigour. These genes will be explored in the model plant system Arabidopsis. These findings will be extended to enhance seed vigour in the crop species Brassica oleracea. Mutations within newly characterized vigour genes will be identified in different Brassica plants. Together with industrial partner Syngenta, the vigour of these new Brassica seeds will be characterized. This will lead to the identification of varieties which can be used directly in breeding programs to enhance seedling establishment, field crop performance and yield. We have previously shown that the size, shape and arrangement of cells can influence the early stages of seed germination in response to growth-promoting gene expression, such as expansin. This observation highlighted the presence of mechanical constraints on plant growth. How these constraints affect the growth of seedlings however remains unknown. Understanding the mechanical basis of the seed to seedling transition is of central importance to understanding the establishment of crops in the field and seed vigour. Using a combination of 3D image analysis and mechanical modelling, the relationship between growth promoting gene expression and seedling growth will be established. In this way the mechanical basis of seedling establishment and seed vigour will be uncovered.Enhancing Brassica seed vigour will increase both crop yields and food security during this period of rapid climate change. The findings in this project may in turn may in turn be extended to other crop species.

种子是绝大多数人类农业的起点和终点。每年的全球种子贸易目前价值超过340亿英镑，高质量种子的生产和销售是这个行业的基础，这些种子发芽均匀、迅速。在作物形成之前，种子在田间经历了一系列的胁迫。这些包括低水应力和来自致密土壤的机械阻抗。种子活力是指种子在广泛的环境条件下发芽和成苗的能力，它决定了作物在田间的成功成苗。这是产量的一个关键决定因素，因为没有植物导致没有最终产品可以收获。改善作物的这一特性是农业工业的主要目标，然而，对活力的潜在机制仍然知之甚少。植物细胞的生长是一个由内部胀压推动周围细胞壁的机械过程。当周围的细胞壁被削弱时，细胞就会变大，并因内部膨胀而屈服。已经确定了编码分泌到细胞壁并改变其结构组成和强度的蛋白质的基因。一旦这种蛋白质被命名为扩张蛋白，它的作用是放松细胞壁结构，允许细胞生长。在没有细胞分裂的情况下，种子到幼苗的过渡完全通过细胞扩增来驱动。产生足够的机械力来抵消外部应力的能力决定了幼苗在各种环境条件下生长的能力，从而具有旺盛的生命力。增加膨胀素的表达可以使幼苗在通常限制这一过程的胁迫条件下建立。因此，种子活力可以被认为是一种机械驱动的农艺性状，而膨胀素表达的控制是一个目标。本项目采用跨学科的方法来揭示种子到幼苗转变和种子活力的遗传因素和机械基础。我们以前鉴定的蛋白质代表高可信度的候选调节膨胀蛋白基因表达。增加扩增基因的表达可以提高种子活力，使这些遗传靶点成为增强种子活力的靶点。这些基因将在拟南芥模式植物系统中进行探索。这些发现将扩展到提高作物品种甘蓝的种子活力。新鉴定的活力基因突变将在不同的芸苔属植物中鉴定。与工业合作伙伴先正达一起，这些新的芸苔种子的活力将被表征。这将导致品种的鉴定，这些品种可以直接用于育种计划，以提高幼苗的建立，田间作物的性能和产量。我们之前已经证明，细胞的大小、形状和排列可以影响种子萌发的早期阶段，以响应生长促进基因的表达，如膨胀蛋白。这一观察结果突出了植物生长受到机械约束的存在。然而，这些限制因素如何影响幼苗的生长仍然未知。了解种子到幼苗转变的机械基础，对于了解作物在田间的建立和种子的活力至关重要。利用三维图像分析和力学建模相结合的方法，建立促生长基因表达与幼苗生长之间的关系。通过这种方式，将揭示幼苗建立和种子活力的机械基础。在这个气候快速变化的时期，增强芸苔种子活力将提高作物产量和粮食安全。这个项目的发现可能反过来又可以推广到其他作物物种。