Natural diversity of Frankia strains in actinorhizal root nodules from promiscuous hosts in the family Myricaceae.

ABSTRACT: Actinorhizal plants invade nitrogen-poor soils because of their ability to form root nodule symbioses with N(2)-fixing actinomycetes known as Frankia. Frankia strains are difficult to isolate, so the diversity of strains inhabiting nodules in nature is not known. To address this problem, we have used the variability in bacterial 16S rRNA gene sequences amplified from root nodules as a means to estimate molecular diversity. Nodules were collected from 96 sites primarily in northeastern North America; each site contained one of three species of the family Myricaceae. Plants in this family are considered to be promiscuous hosts because several species are effectively nodulated by most isolated strains of Frankia in the greenhouse. We found that strain evenness varies greatly between the plant

SUBMITTER: Clawson ML 

PROVIDER: S-EPMC91602 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature