Seaweed-derived biostimulants for sustainable crop production. A review

The increasing concerns over climate changes and environmental impacts of synthetic agrochemicals have led to a growing interest in natural alternatives such as seaweed-based biostimulants. These extracts contain diverse bioactive compounds, including phytohormones, polysaccharides, proteins, polyphenols, and vitamins, which contribute to enhanced plant growth, stress tolerance, and soil health. Seaweed biostimulants have demonstrated their ability to improve germination, growth, and yield under both optimal and stressful conditions. Additionally, seaweed-derived compounds influence microbial communities, promoting beneficial interactions that enhance soil structure and fertility. Their different mode of applications further expands their utility in modern agriculture. Despite their numerous advantages, challenges remain regarding cultivation, large-scale production, and regulatory frameworks. Further research is needed to optimize extraction methods, elucidate mechanisms of action, and explore economic feasibility. This systematic review brings focus to the potential of seaweed-based biostimulants as sustainable agricultural inputs, discussing their chemical composition, mechanisms of action, techniques of extraction, application strategies, challenges and future perspectives for improving crop productivity and resilience.