Open AccessTransconjugants of Agrobacterium radiobacter harbouring sym genes of Rhizobium galegae can form an effective symbiosis with Medicago sativa
Author(s) -
Novikova Natalie,
Safronova Vera
Publication year - 1992
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1992.tb05107.x
Subject(s) - biology , agrobacterium , complementation , rhizobiaceae , medicago sativa , symbiosis , sinorhizobium meliloti , rhizobium , nod , microbiology and biotechnology , rhizobia , mutant , botany , gene , genetics , bacteria , transformation (genetics)
It is known that the Rhizobium galegae genomes contain megaplasmids. The suicide vector pSUP2111 with nifH geene of R. meliloti was introduced into the strains CIAM 0703 and CIAM 0711 of R. galegae inducing effective nodules on Galega orientalis plants. The formation of self‐transmissible megaplasmids was observed. The megaplasmid transfer into non‐nodulating R. meliloti mutants resulted in partial complementation of the nodulation defect in recipient strains though only one transconjugant showed the nitrogen‐fixing activity in symbiosis with alfalfa and another one in symbiosis with G. orientalis plants. Among the Agrobacterium strains harbouring R. galegae megaplasmids there were four classes of transconjugants: (1) Nod + Fix − in symbiosis with goat's rue plants (three strains); (2) Nod + Fix − on Medicago sativa (two strains); (3) Nod + Fix + on M. sativa (five strains); (4) Nod − with both plant hosts (11 strains).