Microbial extracellular polymeric substances (EPS) have been shown to enhance soil structure, nutrient availability, microbial activity, and plant root development. It was therefore hypothesized that they could serve as a valuable natural resource for increasing agricultural productivity. This study investigated the effects of Rhizobium tropici-derived EPS on the growth and yield of sweet corn (Preaches and Cream) on soil freshly amended with EPS and in rotation following the cultivation of Black-eyed peas (BEP) on EPS-amended soil. Microbial EPS without BEP increased available soil phosphorus (avP), soil pH, Nitrate-N, and cation exchange capacity (CEC). Moreover, EPS increased sweet corn plant height, fresh and dry biomass, and improved ear formation and seed yield. Fresh EPS application boosted seed yield by 18.4%, while the residual effects of EPS and BEP increased sweet corn yield by 22.8%. The residual effects of EPS and BEP alone raised seed yield by 7.0% and 15.8%, respectively. We conclude that microbial-derived EPS can serve as a biofertilizer to promote the growth of BEP and sweet corn in crop rotation, offering a sustainable alternative to chemical fertilizers. This study emphasizes the potential role of microbial EPS in environmentally friendly agriculture.
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