The biofertilizer and biostimulant properties of a mixture of Spirulina sp. and Chlorella vulgaris biomass in Musa AAA Cavendish variety Valery seedlings
The agricultural sector is a major contributor to environmental pollution, including greenhouse gas emissions. Banana cultivation also significantly impacts these conditions due to the intensive use of commercial fertilizers. These fertilizers not only disrupt ecosystems and pollute water sources but also underscore the urgent need for sustainable alternatives. This research evaluated the potential of a biomass mixture comprised of the microalga Chlorella vulgaris and the cyanobacterium Spirulina sp. as a biofertilizer and biostimulant for Musa AAA Cavendish var. Valery seedlings grown under greenhouse conditions. The biomass was produced using cost-effective, large-scale methods and subsequently harvested, dried, and characterized for its physicochemical properties, which revealed a high organic matter content. Eight comparative treatments were applied as dry soil amendments at varying concentrations and were evaluated against a commercial fertilizer. During the study, various morphological traits of plants, pigment content, and soil properties were measured both before and after treatment. The results showed that biomass applications at 2 g/kg and 4 g/kg (T3 and T4) matched or surpassed the effectiveness of the commercial fertilizer in promoting pseudostem length, dry weight, leaf area, chlorophyll concentration, photosynthetic efficiency, nitrogen uptake, and CO₂ assimilation for banana growth and yield. Additionally, the microalgal biomass improved soil quality by increasing organic matter and the availability of essential micronutrients. These findings suggest that microalgal biomass can effectively replace chemical fertilizers, fostering a more sustainable banana cultivation system with a reduced carbon footprint. The study’s results recommend a phased application strategy: using T3 during the vegetative stage to stimulate early growth and T4 during the reproductive stage to support fruit development. This approach may optimize nutrient uptake and enhance overall crop productivity in an environmentally friendly manner
