PHASEOLUS-VULGARIS IS A NONSELECTIVE HOST FOR NODULATION

A systematic analysis of the symbiotic phenotype on Phaseolus vulgaris of tropical rhizobia isolated from a variety of leguminous plant spec ies and of classified type strains from the genera Rhizobium, Sinorhiz obium, Mesorhizobium, Bradyrhizobium and Azorhizobium was performed. D epending on the bean cultivar, between 80 and 90% of the tested rhizob ia were able to nodulate. A minority of these nodules were also nitrog en-fixing. A detailed microscopic analysis of the induced nodules or n odular structures revealed that the interaction between these strains and P. vulgaris was arrested at different stages of the interaction. O ur results show that P. vulgaris is able to perceive signals for nodul ation from many rhizobia although most of the interactions are not eff ective. (C) 1995 Federation of European Microbiological Societies. Pub lished by Elsevier Science B.V. All rights reserved.