Community Genomics of Local Adaptation in Medicago Truncatula

主持：Sergey Nuzhdin，南加州大学主持：Eric von Wettberg，加州大学戴维斯豆科植物，包括农业上重要的物种大豆、苜蓿、豌豆和豆类，与根瘤菌合作，将大气中的氮转化为生物可利用的氨。这一特性使豆科植物能够殖民边缘栖息地，并为研究共同进化如何促进对压力环境的适应提供了一个理想的系统。模式豆科植物紫花苜蓿是苜蓿的近亲，在北非的高盐土壤和正常土壤中都能自然生长。这个研究项目将与突尼斯和法国的研究人员合作，利用基因组资源来了解Medicago及其合作伙伴Sinorhizobium是如何适应盐碱地的。这项研究的主要目标是确定基因和遗传和生物化学网络，这些基因和遗传和生物化学网络是适应盐和非适应盐的种群之间生态差异的基础。通过测量这些基因和网络在植物所经历的自然条件下的影响，这项研究具有连接遗传学、生态学和进化的独特潜力。声明更广泛的影响土壤盐碱化是一个日益严重的问题，有可能影响到全世界三分之一的农业用地。因此，了解包括盐度在内的非生物因素如何影响共生效率对发达国家和发展中国家的农业都是一个重要的挑战。由于苜蓿是一种模式物种，因此本研究确定的基因和途径将直接适用于许多农业上重要的豆科植物的育种工作，并更广泛地应用于整个植物生物学。这个项目的跨学科和跨洲性质进一步提供了一个特殊的培训机会。这个项目将整合突尼斯和美国的团队——由公共机构（加州大学戴维斯分校）和私人机构（南加州大学）慷慨的配套资金提供支持——通过人员交流在突尼斯合作进行实地实验。突尼斯的学生和学者将被美国机构接待，在那里他们将从事研究，参加量身定制的课程，并建立有助于促进其专业发展的联系。美国本科生和研究生将受益于实践研究经验、个人指导项目以及参加北非讲习班和会议的机会。这项研究产生的所有数据将在http://nlab.usc.edu上公开提供。项目网站将公开发布数据和项目更新。基因分型阵列以及收集的基因型和表型数据将作为社区资源，为未来的Medicago工作提供支持。这项研究的结果将发表在同行评议的开放获取期刊上，供美国和非洲媒体查阅，并由该团队的初级成员在全球各地的国际会议上介绍。

PI: Sergey Nuzhdin, University of Southern CaliforniaCo-PI: Eric von Wettberg, University of California, DavisLegume plants, including the agriculturally important species soybean, alfalfa, pea, and bean, collaborate with rhizobium bacteria to convert atmospheric nitrogen to biologically available ammonia. This property has enabled legumes to colonize marginal habitats and provides an ideal system to study how coevolution promotes adaptation to stressful environments. The model legume Medicago truncatula is a close relative of alfalfa and grows naturally in both highly saline soils across North Africa as well as on normal soils. In collaboration with Tunisian and French researchers, this research project will use genomic resources to understand how Medicago and its partner Sinorhizobium have adapted to saline soil. The main goal of this research is to identify both the genes and the genetic and biochemcial networks that underlie ecological differences between saline-adapted and non-adapted populations. By measuring the effects of these genes and networks under the natural conditions that plants experience, this research has the unique potential to bridge genetics, ecology, and evolution. Statement broader impacts Soil salinisation is a growing problem with the potential to impact up to one third of agricultural land world-wide. Thus, understanding how abiotic factors, including salinity, impact symbiotic efficiency represents an important challenge for agriculture both in the developed and developing world. Since Medicago truncatula is a model species, the genes and pathways identified in this research will be directly applicable to breeding efforts to improve many agriculturally important legumes and more broadly to plant biology as a whole. The interdisciplinary and inter-continental nature of this project further provides an exceptional training opportunity. This project will integrate Tunisian and American teams-facilitated by generous matching funds from public (UC Davis) and private (USC) institutions-by cooperatively performing field experiments in Tunisia and through the exchange of personnel. Tunisian students and scholars will be hosted at the US institutions where they will engage in research, undertake individually-tailored coursework, and make contacts that will spur their professional growth. American undergraduate and graduate students will benefit via hands-on research experience, individual mentored projects, and the opportunity to participate in workshops and conferences in North Africa. All data generated by this research will be made publicly available at http://nlab.usc.edu. The project website will be publicly accessible with released data and project updates. The genotyping array, and the genotype and phenotype data collected will serve as a community resource enabling future work on Medicago. The results of this research will be published in peer-reviewed open-access journals, made accessible to the American and African media, and presented by junior members of the team at international meetings across the globe.