Application of <i>Sargassum muticum</i> as a nature-based fertilizer to enhance the growth of <i>Capsicum annuum</i> L. plants

Macroalgae, based on their content in bioactive molecules, are solicited for sustainable crop production. This study explores the use of Sargassum muticum from Moroccan coasts, as a biofertilizer for Capsicum annuum L. The biochemicals and mineralogical characterization of S. muticum confirmed its richness in protein, sugar, nitrogen, macro- and micro-elements. Thus, biomass analysis revealed the presence of indole-3-butyric acid (IBA) at 0.14 mg. g−1. C. annuum were exposed to 5, 20, and 30 g. kg−1 of S. muticum and were compared to controls. Results showed improvements in plant growth parameters. Photosynthetic activity, minerals, protein, and total sugar content, were also enhanced mainly with 20 g. kg−1. The fruits nutritional yield was significantly improved. Nitrogen, phosphorus, and potassium contents were of 95.2, 136.8, and 639.2 mg·g−1 dry weight. The obtained results encourage the application of S. muticum as an environmentally friendly biofertilizer for promoting sustainable crops, and reducing the adverse effects of conventional chemical fertilizers.