Efficacy and competition between effective and ineffective strains of Pigeonpea Rhizobium

The main criteria used in selection of Rhizobium strains for legume inoculant production is the ability to compete with native rhizobia. Efficacy and competition are known to very from strain to strain and host to host. Effective and ineffective isogenic mutants of Rhizobium were examined for their acceptance by the host. Competition beetween effective and ineffective mutants will indicate whether the host exercices selection towards effective strains or whether effective strains are more competitive.