期刊
JOURNAL OF BIOGEOGRAPHY
卷 31, 期 3, 页码 425-434出版社
BLACKWELL PUBLISHING LTD
DOI: 10.1046/j.0305-0270.2003.01030.x
关键词
Amphicarpaea; biogeography; coevolution; phylogenetic congruence; symbiosis
Aim Relationships of eastern Asian and eastern North American populations of legumes in the genus Amphicarpaea Elliot ex. Nuttall (Phaseoleae-Glycininae) and their root nodule bacteria (Bradyrhizobium Jordan) were analysed to test whether both organisms share an identical biogeographic history. Location Japan and eastern North America (New York and Illinois). Methods Sequences of three plant genes (chloroplast trnL region, nuclear ribosomal ITS, and histone H3-D) and a segment of the bacterial ribosomal region (partial 16S rRNA and 23S rRNA genes, and the 16S rRNA-23S rRNA ITS) were used to analyse phylogenetic relationships. Results For plants, Japanese populations formed a sister group to a well-supported clade of all North American genotypes. For nodule bacteria associated with Amphicarpaea, isolates from North America did not form a single clade relative to Asian genotypes. Japanese Bradyrhizobium isolates were closely related to particular sub-groups of North American bacteria (lineages 'B' and 'C'), with other American bacteria branching earlier. Main conclusions Plants and bacteria showed clear deviations from a pattern of parallel cladogenesis. The most basal Amphicarpaea lineage was associated with a recently-diverged bacterial group, while one recently-diverged plant lineage had symbionts that branched in a basal position relative to the other Amphicarpaea bacteria. When analysed with data on symbiotic compatibility from inoculation experiments, the molecular phylogenies suggested that for plants, at least one transition has occurred toward more promiscuous nodulation behaviour. Among bacteria, strains with narrow host range on Amphicarpaea appear to be ancestral to symbiotic generalists.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据