Influence of Sargassum Extract and Mineral Fertilizer on the Yield of Pinto Bean (Phaseolus vulgaris L.) cv. San Rafael

Abstract

Bean seeds are of significant global importance due to their high nutritional value. Mineral fertilizers are commonly used to enhance crop productivity; however, their excessive application can be detrimental to the environment. An alternative is the use of sargassum extracts, which both reduce the demand for mineral fertilizers and help mitigate the environmental and economic problems caused by massive sargassum accumulations on coastal areas. This study evaluated the ef ficacy of combining organic fertilization based on sargassum extract (S) with mineral fertilizer (M) at dif ferent doses in pinto bean cultivation. The experiment was conducted over two cropping cycles using three concentration levels of Sargassum (S1, S2, S3), three of mineral fertilizer (M1, M2, M3), their combinations (S/M), and an unfertilized control (C-), in a randomized experimental design. Application of either M or S fertilizers increased yield compared with the control. The S2/M2 and S3/M2 combinations increased seed weight by 5% and 10%, respectively, relative to M3 alone, while S1/M2 and S2/M1 produced seed weights comparable to M3. In contrast, S3/M1 resulted in a 7% reduction in seed weight compared with M3. Neither the DPPH radical scavenging activity nor the anthocyanin content of the seeds was af fected by fertilizer treatments. These findings indicate that the combined use of sargassum extract and mineral fertilizer is a promising strategy to reduce mineral fertilizer inputs without compromising yield, while also valorizing sargassum—a low-cost material that poses environmental challenges but contains beneficial compounds for plants.