Behaviour of a sym plasmid from Rhizobium ‘hedysari’ in different Rhizobium species

The symbiotic plasmid pRHc1J of Rhizobium ‘hedysari’ has been transferred to different Rhizobium species. It expression and incompatibility with the recipient resident plasmids as well as the effect of the host plants on the selection of Rhizobium symbiotic information has been studied. When the symbiotic plasmid pRHc1J was transferred to Nod +Fix + Rhizobium species, it underwent specific deletions, either spontaneously or after the passage of transconjugants through plants, leading to the loss of some essential nod genes.