Coevolution and Specificity in a Legume-Rhizobium Symbiosis

这一研究项目将能够分析一年生原生豆科植物与其相关根瘤细菌之间的共同进化过程。这项工作将回答关于豆科植物-根瘤菌互惠共生中种内分化进化的三个基本问题：(1)植物和细菌是否表现出相似的种群分化模式？(2)来自每个本地种群的根瘤菌是否优先适应以促进共生植物的生长？(3)哪些约束限制了极端共生多样化或极端专业化的表型进化？这项工作的主要意义将是通过整合实验室实验、田间实验以及对宿主和细菌种群中遗传结构的联合分析，为植物和微生物如何在自然群落中相互影响生态和进化提供新的见解。

This research project will allow the analysis of, the process of coevolution between a native annual legume and its associated root-nodule bacteria. This work will answer three basic questions about the evolution of intraspecific divergence in symbiotic compatibility in legume-Rhizobium mutualisms: (1) Do plants and bacteria exhibit similar patterns of population differentiation? (2) Are Rhizobium genotypes from each local population preferentially adapted to enhance the growth of co-occurring plant genotypes? (3) What constraints limit the evolution of phenotypes with either extreme symbiotic diversification or extreme specialization? The major significance of this work will be to provide new insights about how plants and microbes influence each other's ecology and evolution within natural communities by integrating laboratory experiments, field experiments, and joint analyses of genetic structure in host and bacterial populations.