Co-inoculation of rhizobia, azospirilla and cyanobacteria for increasing common bean production

Abstract

The combined inoculation of Rhizobium (R. tropici+R. freirei), Azospirillum brasilense, and Anabaena cylindrica, a diazotrophic cyanobacterium, is a technology that has not yet been tested and established in the production of the common bean (Phaseolus vulgaris). The inoculation may be a promising strategy for increasing crop productivity by combining the benefits of biological nitrogen fixation with the production of plant growth phytohormones. Therefore, the objective of this study was to evaluate the co-inoculation of Rhizobium, Azospirillum brasilense, and Anabaena cylindrica as an alternative method for optimizing the symbiotic performance and development of the common bean at greenhouse conditions. The treatments were as follows: (T1) control without N and inoculation, (T2) N addition (100 kg N ha-1), (T3) Riz (addition of R. tropici+R. freirei), (T4) Azo (Azospirillum brasilense addition), (T5) Ana (Anabaena cylindrical addition), (T6) Riz+Azo, (T7) Riz+Ana, (T8) Azo+Ana, (T9) Riz+Azo+Ana. We used a completely randomized experimental design with four replications. The co-inoculation of Riz+Azo+Ana promoted plant height, root length and volume, shoot dry matter, accumulated shoot N, number and dry matter of nodules at flowering, number of grains per pod, hundred seed weight, and grain production of the common bean, contributing to increased yield per plant. We observed an increase in common bean grain yield ranging from 62 to 84% after double and triple co-inoculation of rhizobia with azospirilla and/or cyanobacteria, with the highest yield observed in the plants inoculated with Riz+Azo+Ana (84%), similar to those observed in plants after N addition. However, field experiments are necessary to elucidate the performances of the inoculated beneficial microorganisms.

Design and validation of cyanobacteria-rhizobacteria consortia for tomato seedlings growth promotion

“…Actually, both partners can produce plant growth promote biomolecules 53,54 . Recently, Horácio et al 55 evaluated the effects of co-inoculation with cyanobacteria and bacteria, getting an increase in nodulation, plant growth and production of the common bean, comparing with the untreated controls. This effect is indicative that N fertilization could be replaced by the use of previously selected microbial consortia.…”

Potential of Algae–Bacteria Synergistic Effects on Vegetable Production

“…Recently, Horácio et al (2020) evaluated the effects of coinoculation with a diazotrophic cyanobacterium (Anabaena cylindrica, Ana), Rhizobium (R. tropici + R. freirei, Riz), and A. brasilense (Azo) on the development of the common bean under greenhouse conditions. Grain production in the plants co-inoculated with Ana + Riz + Azo and fertilized with N (100 kg N ha −1 ) was 84.4% and 86.3% higher than that of untreated controls, respectively.…”

“…Grain production in the plants co-inoculated with Ana + Riz + Azo and fertilized with N (100 kg N ha −1 ) was 84.4% and 86.3% higher than that of untreated controls, respectively. This indicates that N fertilization can be replaced by co-inoculation with selected cyanobacterialbacterial strains (Horácio et al, 2020). In addition, Gavilanes et al (2020) conducted two field experiments to assess the efficacy of co-inoculation of A. cylindrica with A. brasilense on the yield performance of four maize cultivars in two locations (Londrina and Faxinal in Paraná, Brazil).…”

Photoautotrophs–Bacteria Co-Cultures: Advances, Challenges and Applications

“…Moreover, the data pointed out that the photosynthetic compounds produced by algae, such as carotenoids, could improve the plant crops in terms of quality and quantity, and furnish support in stress conditions as can be present during the summer season. Analogues results, related to growth promotion, productivity and quality of the plants, were reported also for common bean, maize and onion by administering on crops a preparation of algae and bacteria [105][106][107]. For all these reasons, it is reasonable to suppose that co-cultures systems can be more effective in enhancing microbial diversity in the soil, resistance to plant diseases and productivity of vegetable crops.…”