PHYLOGENETIC STUDIES ON UNCULTURED FRANKIA POPULATIONS IN NODULES OF DATISCA-CANNABINA

Part of the 16S rRNA gene was amplified directly from uncultured endop hyte populations within the root nodules of Datisca cannabina and thre e strains isolated from nodules of Alnus glutinosa (AgKG'84/4), Coriar ia nepalensis (Cn3), and D. cannabina (Dc2). Sequence comparison based on 930 nucleotides indicated that the endophyte of D. cannnbina nodul es belongs to the genus Frankia and is highly related to the endophyte of C. nepalensis root nodules. The relatedness of the endophytes of C . nepalensis and D. cannabina nodules was also reflected by closely re lated nifH sequences amplified from the nodules. 16S rRNA sequence ana lysis of the noninfective strains obtained from both D. cannnbina (Dc2 ) and C. nepalensis (Cn3) nodules also revealed the close relationship of these strains to the genus Frankia.