The effects of early probiotic supplementation on the germination of Arabidopsis thaliana

The agricultural industry uses fertilizer to produce enough food for the world’s robust and growing population. However, the use of fertilizers is associated with an increase in soil degradation, which will lead to a decrease in crop production within the next decade. This soil degradation is due, at least in part, to the long-term use of oil-based synthetic fertilizers. These fertilizers deplete the soil of nutrients and bacteria essential to plant growth. It is critical to find solutions to support crop production to sustain the robust global population. As a result, this study was conducted to investigate how probiotic bacteria, like Rhizobium leguminosarum, Bacillus subtilis and Pseudomonas fluorescens, can impact the growth of Arabidopsis thaliana when applied to the seeds. The effect of multiple probiotic genera on early root growth was evaluated through the generation of various bacterial solutions composed of different quantities and combinations of probiotic bacteria, treating Arabidopsis seeds with these probiotic solutions and placing the seeds on agar plates to germinate with the evaluation of early root growth. We hypothesized that solutions with multiple bacterial species compared to those with only a single bacterial species would promote seed germination more effectively. The results suggest that there was no statistically significant difference in the total root lengths of each group, but there was a statistically significant difference in the number of root branches. Overall, treatment groups with probiotic species of bacteria promoted root branching more than treatment groups with no bacteria. Multiple species of these bacteria, especially the groups containing R. leguminosarum, stimulated more root branching than treatment groups with one species of bacteria. Further research on how different bacterial genera affect root characteristics may support the development of alternative and sustainable bacteria-based fertilizers, which can aid in reversing the effects of soil degradation.