Genetic Analysis of Natural Variation in the Control of Water Use Efficiency and Response to Drought Stress in Brassica rapa

油菜水分利用效率控制和干旱胁迫响应自然变异的遗传分析

• 批准号: 1025965
• 负责人: C. Robertson McClung
• 金额: $ 386.79万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2018-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1025965&HistoricalAwards=false
• 关键词: Genetic; Analysis; Natural; Variation; Control

PI: C. Robertson McClung (Dartmouth College)CoPIs: Cynthia Weinig and Brent E. Ewers (University of Wyoming), Richard M. Amasino (University of Wisconsin - Madison), and Todd C. Mockler (Oregon State University)This project investigates the genetic underpinnings of plant water use in the crop species Brassica rapa. Water-use efficiency is a critical determinant of yield in crops and fitness in wild species. The match between a plant's endogenous circadian rhythm and external abiotic conditions, including water stress, can dramatically affect physiological functions such as chlorophyll production, carbon fixation, and water loss through transpiration. Brassica rapa exhibits a strong association between circadian rhythms and both transpiration and water-use efficiency. Preliminary studies exploiting the genetic diversity present in two parental genotypes have identified at least ten genetically defined regions that affect water-use efficiency. Of these, six co-localize with genes affecting circadian clock function. This project will clone and characterize the gene or genes of one region, on Chromosome A7, that explains more than one-quarter of the variation in water-use efficiency. Identifying the underlying locus will be facilitated by experiments where water stress is imposed at the atmospheric and soil levels, and plant measurements quantify the connection between water supply and demand as well as plant carbon fixation and utilization. This project also will characterize the gene expression response to water stress and the influence of time of day on the magnitude of that response. This project will develop genetic resources akin to the maize Nested Association Mapping (NAM) lines that will explore the genetic diversity present in ~20 diverse parents. This should allow the identification of more genetic loci that contribute to water-use efficiency. These in turn will be fine-mapped and cloned, thus enhancing our understanding of the genetic basis of water-use efficiency in crop species. Enhanced understanding of the architecture of water-use efficiency in this crop species should facilitate efforts to breed for enhanced water-use efficiency in a wide range of crop species.Given the profound implications to society of even small changes in crop water use on global hydrology, a thorough understanding of the genetic controls on and natural variation in plant water use and gas exchange is warranted to feed a rapidly growing global population with increasingly limited fresh water supplies. This project offers innovative educational opportunities at the high school, undergraduate, predoctoral and postdoctoral levels in quantitative molecular and classical genetic analysis and plant physiology. The project will train middle and high school teachers and develop educational modules that permit K-16 students to do hands on studies in classical and molecular genetics using a rapid-cycling strain of B. rapa. Annual summer institutes at University of Wisconsin - Madison will enhance the value of a resource to teach classical, molecular, and biochemical genetics at the K-12 and undergraduate levels that has already gained widespread acceptance in the classroom. Thus, the outreach aspects of this project should be manifest on a national level. All data, biological materials, and teaching materials will be freely available through the DIURNAL website (http://diurnal.cgrb.oregonstate.edu/diurnal_about.html), public databases [NCBI Short Read Archive (SRA) (http://www.ncbi.nlm.nih.gov/Traces/sra/sra.cgi?), Gene Expression Omnibus (GEO) (http://www.ncbi.nlm.nih.gov/geo/), Brassica.info (www.brassica.info)] and/or repositories [Arabidopsis Biological Resource Center (ABRC) (http://abrc.osu.edu/) and the Wisconsin Fast Plants Program (WFPP) (http://www.fastplants.org/)].

PI：C。罗伯逊·麦克朗（达特茅斯学院）CoPI：辛西娅·维尼和布伦特E。Ewers（怀俄明州大学），Richard M. Amasino（威斯康星州-麦迪逊大学）和托德C. Mockler（俄勒冈州州立大学）该项目调查了作物物种芜菁中植物水分利用的遗传基础。 水分利用效率是作物产量和野生物种适合度的关键决定因素。 植物的内源性昼夜节律和外部非生物条件（包括水分胁迫）之间的匹配可以显著影响生理功能，如叶绿素产生、碳固定和通过蒸腾作用的水分损失。芜菁表现出强烈的昼夜节律之间的关联和蒸腾和水分利用效率。 利用两个亲本基因型中存在的遗传多样性的初步研究已经确定了至少十个影响水利用效率的遗传定义区域。 其中，6个与影响生物钟功能的基因共定位。该项目将克隆和表征染色体A7上一个区域的基因，该区域解释了水利用效率的四分之一以上的变化。 通过在大气和土壤水平上施加水分胁迫的实验，以及对植物的测量，将水的供应和需求以及植物的碳固定和利用之间的联系量化，将有助于确定潜在的地点。该项目还将描述基因表达对水分胁迫的反应以及一天中的时间对这种反应的影响。该项目将开发类似于玉米巢式关联作图（NAM）系的遗传资源，探索约20种不同亲本的遗传多样性。 这将使更多的基因位点，有助于水的利用效率的确定。这些基因又将被精细绘制和克隆，从而提高我们对作物物种水分利用效率的遗传基础的理解。 提高对这一作物品种水分利用效率结构的理解，应有助于努力培育提高大范围作物品种水分利用效率的品种。鉴于作物水分利用对全球水文的影响即使很小，对植物水分利用和气体交换的遗传控制和自然变异的透彻理解，对于养活快速增长的全球农业来说，淡水供应日益有限。该项目提供了创新的教育机会，在高中，本科，博士前和博士后水平的定量分子和经典遗传分析和植物生理学。该项目将培训初中和高中教师，并开发教育模块，使K-16学生能够使用快速循环的B菌株进行经典和分子遗传学研究。拉帕。威斯康星州-麦迪逊大学的年度暑期研究所将提高K-12和本科水平的经典，分子和生物化学遗传学教学资源的价值，这些资源已经在课堂上获得了广泛的接受。因此，该项目的外联工作应体现在国家一级。所有数据、生物材料和教学材料都将通过DIURNAL网站（http：//diurnal.cgrb.oregonstate.edu/diurnal_about.html）、公共数据库[NCBI短读档案（SRA）（http：//www.ncbi.nlm.nih.gov/Traces/sra/sra.cgi？），gov/geo/）、www.example.com（www.brassica.info）]和/或储存库[拟南芥生物资源中心（ABRC）（http：//abrc.osu.edu/）和威斯康星州快速植物计划（WFPP）（http：//www.fastplants.org/）]。Brassica.info