Evolutionary and Functional Analysis of Plant Adaptation to Salinity

非生物胁迫，如土壤盐碱化，导致全球农业年产量大幅下降。据估计，仅在美国，土壤盐分每年就会使灌溉作物的产量减少20-30%。除了少数例外，农作物无法适应土壤中盐分升高引起的离子和渗透胁迫。虽然植物生长的耐盐性存在遗传变异，但对这种变异的基因和途径知之甚少。本项目将使用：1)对芸苔科（芥菜科）物种进行进化分析，以了解驱动植物适应土壤盐度的机制；2)对芸苔科中具有极端耐盐性差异的亲缘物种拟南芥（Arabidopsis thaliana）和Eutrema salsugineum （Thellungiella halophila）进行分子遗传比较，以了解是否蛋白质或基因调控序列的变化驱动了这种适应进化；3)分析拟南芥种质资源的自然变异，揭示遗传变异与植物盐度适应的关系。这些研究的结果将确定在盐水环境中提高作物生长和产量所需的基因、途径和修改。该项目还将通过以下方式加强研究、培训和外联的基础设施：1)继续在亚利桑那大学指导本科生和研究生，并培养博士后研究人员；2)与亚利桑那大学K-12教育研究生、生物技术项目和KEYS暑期实习项目合作，制作综合教学模块，介绍进化、遗传、为教师和高中生提供研究经验；3)参加南亚利桑那数学、科学和技术趣味项目（6000名4 -8年级学生）和亚利桑那大学植物科学家庭之夜。

Abiotic stresses such as soil salinity cause major reductions in annual agricultural yields worldwide. It has been estimated that, in the United States alone, soil salinity reduces irrigated crop yields by 20-30% annually. With few exceptions, crop plants are unable to adapt to the ionic and osmotic stresses induced by elevated levels of salt in the soil. While genetic variation for plant growth in salinity (salt tolerance) exists, little is known about the genes and pathways underlying this variation. This project will use: 1) evolutionary analyses of species within the Brassicaceae (the mustard family) to understand mechanisms that drive plant adaptation to soil salinity, 2) molecular genetic comparisons of Arabidopsis thaliana and Eutrema salsugineum (Thellungiella halophila), related species within the Brassicaceae with extreme differences in salt tolerance, to understand if changes in proteins or gene regulatory sequences drive this adaptive evolution and, 3) analyses of natural variation within Arabidopsis accessions to uncover the relationship between genetic variants and plant adaptation to salinity. Results from these studies will identify the genes, pathways, and modifications needed to enhance crop growth and yield in saline environments.This project will also be used to enhance the infrastructure of research, training, and outreach through: 1) continued instruction of undergraduate and graduate students and training of postdoctoral researchers at the University of Arizona, 2) collaboration with the University of Arizona Graduate Fellows in K-12 Education, the BIOTECH Project, and the KEYS Summer Internship Program, to produce integrated teaching modules to introduce evolutionary, genetic, and genomic approaches for investigating plant adaptation in K-12 classrooms and to provide teachers and high school students with research experiences and, 3) participation in the Southern Arizona Math, Science, and Technology Funfest program (6,000 4th-8th graders) and the University of Arizona Plant Science Family Nights.