Water deficit is one of the main factors limiting soybean productivity, impairing plant growth and reducing crop yield potential. In this context, the use of plant growth-promoting rhizobacteria (PGPR) has emerged as a promising strategy to enhance plant tolerance to abiotic stresses and improve crop development. This study aimed to evaluate the effects of soybean seed inoculation with Bacillus aryabhattai on seed physiological performance during germination and plant growth under water-deficit conditions. Two experiments were conducted. In the first experiment, a completely randomized design was adopted in a factorial arrangement, evaluating seed inoculation (with or without aryabhattai) and water availability (with or without water deficit). Shoot and root length, as well as shoot and root fresh and dry biomass, were determined. In the second experiment, the seed physiological performance during germination of inoculated and non-inoculated seeds was evaluated by assessing seedling biomass accumulation. Seed inoculation significantly promoted shoot and root growth under both well-watered and water-deficit conditions. Inoculated plants subjected to water restriction exhibited greater length and biomass accumulation than non-inoculated plants, demonstrating enhanced tolerance to drought stress. In addition, inoculation increased shoot biomass accumulation during the seedling stage, indicating greater early vigor. Overall, the results demonstrate that Bacillus aryabhattai has considerable potential as a soybean seed inoculant, promoting plant growth and contributing to improved crop resilience under water-deficit conditions.
Jean Roberto Ruaro, Sérgio Miguel Mazaro, Maira Cristina Schuster Russiano et al.· REMUNOM· 0 citations
Drought is one of the major abiotic stresses limiting productivity worldwide, highlighting the need for sustainable strategies to improve crop resilience under water-limited conditions. This study evaluated the effects of the plant growth-promoting bacteria Bacillus aryabhattai and Pseudomonas fluorescens, applied individually or in combination, on soybean growth under well-watered and water-deficit conditions. The experiment was conducted in a completely randomized design arranged in a 2 × 4 factorial scheme, consisting of two irrigation regimes (well-watered and water deficit) and four biological treatments (control, B. aryabhattai, P. fluorescens, and co-inoculation with both bacteria). Plant growth variables, including shoot and root length, root volume, fresh biomass, and dry biomass, were evaluated after the stress period. Under well-watered conditions, co-inoculation promoted the greatest fresh root biomass and consistently increased shoot biomass compared with the untreated control. Under water-deficit conditions, B. aryabhattai alone produced the highest fresh root biomass and root volume, demonstrating superior performance in promoting root development during drought stress. Although most variables did not differ significantly among treatments, inoculated plants consistently exhibited greater vegetative growth than non-inoculated plants. These findings demonstrate the potential of B. aryabhattai and P. fluorescens as plant growth-promoting bacteria capable of enhancing soybean development, with B. aryabhattai showing particular promise for improving plant performance under water-limited conditions.
Thiago Ghedin Cappellesso, Sérgio Miguel Mazaro, Maira Cristina Schuster Russiano et al.· REMUNOM· 0 citations