Co-Inoculations with Plant Growth-Promoting Bacteria in the Common Bean to Increase Efficiency of NPK Fertilization

Abstract

Given the hypothesis that co-inoculation with plant growth-promoting bacteria (PGPB) enhances the beneficial effects of Rhizobium tropici with greater mineral nutrition, optimizes biological nitrogen fixation and reduces use of fertilizers in bean plants, the objective of this research was to evaluate the synergistic effects of Rhizobium tropici associated with Azospirillum brasilense, Bacillus subtilis, Pseudomonas fluorescens and their combinations, on increasing the efficiency of NPK fertilization to obtain high winter yields of the (irrigated) common bean in the Cerrado region. The experiment was carried out in the field over two years in a Rhodic Hapludox under a no-till system in Selvíria, Brazil. The experimental design comprised complete randomized blocks with four replications in a 3 × 7 factorial scheme. The treatments consisted of three doses of NPK fertilizer (control—0 kg ha−1 (control); 50% of the recommended dose; 100% of the recommended dose in two parts) and seven doses of inoculation or co-inoculation (control; Rhizobium tropici; R. tropici + Azospirillum brasilense; R. tropici + Bacillus subtilis; R. tropici + Pseudomonas fluorescens; R. tropici + A. brasilense + B. subtilis; R. tropici + A. brasilense + P. fluorescens). The PGPB in the co-inoculations increased the hundred-grain weight, the grain pod−1, the grain plant−1 and the grain yield following the NPK doses. The grain yield of the common bean was increased by co-inoculation with R. tropici + A. brasilense + P. fluorescens without NPK treatments, co-inoculation with R. tropici + P. fluorescens and R. tropici + A. brasilense + B. subtilis with the 50% dose of NPK and co-inoculation with R. tropici + B. subtilis with the recommended dose of NPK fertilizer (100%).

Effect of Azospirillum brasilense Addition and Organic Matter on Irrigation Efficiency, NPK Availability and Wheat Yield (Triticum aestivum L.)

“…The results in Table 5 indicated that the bio-fertilizer application had a significant effect on the soil potassium content, as the F1 bio-fertilizer application recorded the highest average, achieving an increase of 12.85% compared to The F0 no-bio-fertilizer treatment was the lowest average. This may be attributed to the fact that the bio-bacterial fertilizer contributes to increasing the readiness and solubility of some nutrients, including potassium, because of its secretion of organic acids, which leads to a decrease in soil pH [36]. The results also showed that there were significant differences between the treatments of adding organic fertilizers in this Adjective.…”

Contribution of Biofertilizers to Pulse Crops: From Single-Strain Inoculants to New Technologies Based on Microbiomes Strategies

“…The recent literature cites the co-inoculation of common beans with rhizobia and several other bacteria, such as Azospirillum , Bacillus , Paenibacillus , Pseudomonas , Cyanobacteria , and Burkholderia , among others [ 133 , 181 , 182 , 183 , 184 ]. A classic example is the co-inoculation with Rhizobium and Azospirillum , which has been reported to increase yields with return rates between 90% and 114% in commercial farming [ 181 ].…”

Scopping review: use of biofertilizers and humic substances in Phaseolus vulgaris (Fabaceae) for dry zones

“…Regarding the strains that have been used as inoculants to promote the growth of common beans, rhizobia were identified as individual active ingredients: Rhizobium etli and Rhizobium sp. (Suárez et al 2008;Cantaro-Segura et al, 2019), Rhizobium leguminosarum b.v. phaseoli (Mortinho et al, 2022) (Dardanelli et al, 2008;Remans et al, 2008;Yadav et al, 2013;Ferreira et al, 2018) Unlike Colombia, where there is a low supply of commercial inoculants for common beans, in Brazil, 51 registered inoculants based on rhizobia were found.…”