Diversity of Frankia strains nodulating Hippophae salicifolia D. Don using FAME profiling as chemotaxonomic markers.

Twelve Frankia strains isolated from Hippophae salicifolia D. Don or Alnus glutinosa or Comptonia peregrine, showed the significant variation in fatty acid composition viz. palmitic acid (16:0), oleic acid (18:1), linoleic acid (18:2), linolenic acid (18:3), arachidic acid (20:0) and erucic acid (22:1) suggesting the strain specific variability among the Frankia strains. Presence of Erucic acid (22:1), a major component of the oil obtained from the seeds of Brassica sp., albeit in lesser amount in the few studied frankial strains, is the first report. Cluster analysis on the basis of fatty acid composition suggests the presence of two distinct clusters with similitude coefficient ranging from 0.75 to 1.00. Cluster I with HsIi2 showed great divergence from other 11 frankial strains (Cluster II). The two sub groups were distinguished in cluster II: IIa contained five strains isolated from H. salicifolia and these strains are distantly related to the strains of cluster IIb isolated from different host. There is high degree of similarity among the frankial strains of Cluster IIb which suggests that the frankial strains might be evolved from the same ancestor. FAME profiling might be useful tool in the study of polyphasic approach based taxonomy and phylogenetic relationship. Copyright 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim