Isolation and Authentication of Local Rhizobia Nodulating Common Bean (Phaseolus vulgaris L.) in Different Agro-Ecological Zones of Côte d’Ivoire

Abstract

Legumes such as common bean (Phaseolus vulgaris L.) have been introduced into cropping systems for sustainable soil management. Consequently, the loss of fertility of the latter remains a major constraint to bean production because this legume is rarely fertilized, yet it is considered to be a poor nitrogen fixer in the absence of inoculation. To overcome this, this study was undertaken with the objective of seeking efficient local rhizobia in order to pro-pose a bean inoculum formulation. To do this, soil samples taken from twelve localities in the Centre, North and West areas of Côte d’Ivoire were used to trap bean nodulating rhizobia. The ROBA1 bean accession used was sown in pots containing the sampled soils. Seedlings were uprooted at the start of flowering and nodulation was assessed. The isolates obtained were purified and then characterized phenotypically. The infectivity and symbiotic efficacy of these isolates were determined in vitro by the authentication test in which the