Increasing Concentrations of Arthrospira maxima Sonicated Biomass Yields Enhanced Growth in Basil (Ocimum basilicum, Lamiaceae) Seedlings

Abstract

The continued increase in human populations and use of chemical fertilizers remain a threat to the health and stability of human–ecological systems worldwide. To ameliorate this problem and achieve long-term food security, a variety of ecofriendly technologies have been developed, including the production of cyanobacteria-based biofertilizers. This technology can be optimized through experiments that assess how plant growth is enhanced under different biofertilizer concentrations (g L−1). In this study, the biofertilizer capabilities of various concentrations of sonicated biomass (0, 2.5, 5, 10, 20, and 40 g L−1) derived from the cyanobacteria Arthrospira maxima on the growth of basil (Ocimum basilicum, Lamiaceae) were assessed, comparing their effectiveness with that of a positive control, a commercial biofertilizer (OptiMar Algas Marinas®) administered at 4 mL L−1. Generally, increased concentrations led to enhanced growth parameters; however, discernible differences from the negative control (0 g L−1) were often observed only when concentrations exceeded 5 g L−1. Surprisingly, the negative and positive controls often yielded similar results. A chemical composition analysis of A. maxima revealed high concentrations of the phytohormones, macronutrients, and essential amino acids that likely explain how our A. maxima sample enhanced growth in basil. Further research is required to determine how other crop plants respond to different concentrations of A. maxima. Additionally, assessing the feasibility of creating an economically accessible product with a higher concentration of A. maxima is crucial for practical applications.