Fuente: WIPO "tomato" The present disclosure provides methods and systems for production of biostimulants that promote nitrogen use efficiency in plants. Embodiments described include methods of making a biostimulant composition in a bioreactor system that includes two or more containers arranged in series. The bioreactor system may include an established population of a nitrogen use efficiency-promoting microbial strain. The method may include operating the bioreactor system by transferring into the system an aqueous feedstock that comprises a microbial consortium, transferring working fluid between containers of the system, and collecting a product. The method may further include maintaining a concentration of a nitrogen use efficiency-promoting microbial strain in the system.