Doubling soybean grain yield by enhancing biotic interactions and plant nutrition using beneficial mi-crobes and plant bioactive materials for the benefit of farmers and sustainability of agro-ecosystems in sub-Saharan Africa

Soybean plays vital roles in food and nutrition security while generating income for many smallholder farmers in sub-Saharan Africa (SSA). Nevertheless, production is partly constraint by poor and declining soil fertility. Chemical fertilizers are commonly used to mitigate this challenge, however, these chemicals are not readily accessible for many smallholder farmers, and their improper and continuous use increase production costs and may be harmful to biotic interactions in the rhizosphere that enable important plant functions. Sustainable management strategies are encouraged but understanding their role in soil biotic processes is vital for the proper functioning of soil ecosystems. Thus, field studies were conducted in two alternate seasons in Cameroon (August 2021 and March 2022) to evaluate the implications of 13 farm management strategies involving agrochemicals, beneficial microbes and plant bioactive materials on soil biotic interactions and soybean grain yield. The experiment was established as a Randomized Com-plete Block Design with thirteen treatments and four replications. Interestingly, soybean grain yield of plots treated with beneficial microbes, plant bioactive materials and agrochemicals doubled, beneficial microbes and plant bioac-tive materials significantly increased soil microbial biomass total root bacteria, and enzyme activities over the chem-ical and the untreated control treatments. The soil microbial biomass content was significantly harmed by agrochem-icals when compared to the untreated control. These results highlight the importance of beneficial microbes and plant bioactive materials as sustainable management options to increase soybean grain yield, and integrating them in agro-ecosystems could be a holistic approach that is economically viable, resource-conserving, socio-culturally adaptable, and environmentally friendly. Keywords: Beneficial microbes, Plant bioactive materials, Soybean, Sustainability, Yield