Electrical and biological stimulation of blueberry production using semihydroponic system

Blueberries ( Vaccinium corymbosum ) are a good model for evaluating the effects of electrical and biological stimulation on field production; however, the synergistic effect of these stimulations remains unexplored. In this work, we evaluate electrical stimulation (application of an electric field to the semi-hydroponic system to stimulate seeds or plants), biological stimulation (plant growth-promoting bacteria), and the synergistic effect on AtlasBlue ® ‘FMC12-045’ blueberry plants. Field stimulation was carried out at each stage of blueberry development using electrical stimulation (ES), biological stimulation (BSbs), ES + BS, BS + ES, and control (C). During this evaluation, physiological growth parameters, fruit quality, and yields were measured and analyzed using nonparametric tests and one-way ANOVA. For chlorophyll index, L (lightness), Hue angle, and chromatic index (CI), the ES and combined stimulations showed the highest values, with significant differences in Hue angle ( p < 0.05). For total fruit, brix grades, and firmness of blueberries, the CI had numerically higher values than the various stimulations tested in this study, but the differences were not statistically significant ( p > 0.05). Meanwhile, ES + BS stimulation had significantly higher values ( p < 0.05), apparent increases in yields ( p > 0.05), and larger fruits in size than the C. The ES and BS treatments, and their combination, improved certain fruit colorimetric characteristics, thereby enhancing quality. Because the potential synergistic mechanisms between electric fields and bacterial inoculants remain largely unexplored in berry crops, this study establishes a novel baseline for future optimization prior to their possible field application in sustainable agricultural practices.