Physiological and agronomic characteristics of the common bean as affected by multifunctional microorganisms

Abstract

Multifunctional microorganisms (MMs) can have beneficial effects on plants through direct and indirect mechanisms. This study aimed to determine the effect of MMs on shoot and root biomass production; gas exchange; content of macronutrients in the shoots, roots and grains; yield components; and grain yield of common bean plants. A completely randomized design with twenty-six treatments and three replications was used under controlled conditions. Treatments consisted of the application of MMs and their combinations in pairs, with the nine rhizobacteria isolates BRM 32109, BRM 32110 and 1301 (Bacillus sp.), BRM 32111 and BRM 32112 (Pseudomonas sp.), BRM 32113 (Burkholderia sp.), BRM 32114 (Serratia sp.), 1381 (Azospirillum sp.) and Ab-V5 (Azospirillum brasilense); an edaphic fungal isolate T-26 (Trichoderma koningiopsis); and a control (without MMs). These MMs were applied at three time points: microbiolization of the seeds, watering the soil seven days after sowing (DAS) and spraying the plants with 21 DAS. In comparison to the control plants, the isolates 1301 and T-26, in addition to the combinations Ab-V5 + T-26, BRM 32114 + BRM 32110 and 1381 + T-26, provided better results, with an increase of 36.5% in the grain yield, a higher accumulation of biomass (78.0%) and a higher content of N, P and K (42.6, 67.8 and 25.7%, respectively) in the shoots of common bean plants. Therefore, the results allow us to infer that the use of MMs is a good strategy for increasing common bean grain yields.