The diversity of two populations of rhizobia isolated from (30 strains) and (49 strains) growing in northern regions of Quebec, Canada, was determined on the basis of phenotypic characteristics, multilocus enzyme electrophoresis, DNA-DNA homology, and 16S ribosomal DNA sequencing. According to numerical analysis of phenotypic characteristics, strains were divided into four groups. Strains isolated from fell in groups I to III; the latter included reference strains of . All strains isolated from were included in group IV. All strains had nodulation characteristics similar to those of bv. viciae. Strains isolated from originating from an arctic region were usually able to grow at 5°C and were more likely to be tolerant to copper (CuCI · HO, 100 μg/ml) and lead [Pb(CHCOO), 500 μg/ml] than strains isolated from from a boreal zone. However, both populations of strains were adapted to the cold in comparison to reference strains from temperate regions. Each population had similar genetic diversity ( = 0.45), determined by multilocus enzyme electrophoresis of the loci encoding eight enzymes, but the diversity obtained by analyzing all strains including the reference strains ( = 0.58) was higher. Representative strains of both populations showed high levels of DNA homology among themselves and with . Partial sequences of the 16S ribosomal RNA genes were similar to those reported for bv. viciae. We conclude that the strains isolated from and belong to bv. viciae but are distinguishable by growth at 5°C, which is a characteristic related to their geographic origin.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error