Organomineral Fertilization Associated with Inoculation of Rhizobium tropici and Co-Inoculation of Azospirillum brasilense in Common Bean

Abstract

The use of organomineral fertilizers can serve as a nutritional source for crops, ensuring sustainability in the production system. Another alternative approach is through the inoculation and co-inoculation of microorganisms. The objective of this study was to evaluate the development, nutrition, and agronomic yield of common beans through fertilization with the organomineral formula “OMF”, derived from sewage sludge biosolids, combined with Rhizobium tropici inoculation and co-inoculation with Azospirillum brasilense techniques. Three bean cultivars from different commercial groups, Pérola, BRS Esteio, and BRS Pitanga, were tested. They underwent OMF application; OMF application combined with seed inoculation with Rhizobium tropici and re-inoculation; seed co-inoculation with Rhizobium tropici + Azospirillum brasilense prior to sowing; and foliar re-inoculation with Rhizobium tropici + Azospirillum brasilense. The results indicated that seed inoculation, combined with leaf re-inoculation at the V4 stage, resulted in greater bean productivity. The combination of Rhizobium tropici with co-inoculation with Azospirillum brasilense generally led to increased productivity compared to mineral nitrogen fertilization. The exclusive use of OMF enabled development and productivity gains. The Pérola bean cultivar showed better adaptation to the applied treatments. In conclusion, this research suggests that there are benefits to using OMF with symbiotic bacteria and growth promoters.