Evaluating black soldier fly frass as a biofertilizer for soybean cultivation in Mwanza, Tanzania

The adoption of sustainable, locally available biofertilizers presents a promising strategy to address soil fertility constraints in Sub-Saharan Africa, particularly for resource-limited smallholder farmers. This study assessed the effectiveness of Black Soldier Fly Frass (BSFF) as a biofertilizer in enhancing the growth and yield of soybean (Glycine max) under controlled screen house conditions at MATI-Ukiriguru, Mwanza, Tanzania. A Completely Randomized Design (CRD) was employed with seven treatments, five BSFF application rates (0.2–1.0 kg/pot), a chitosan treatment and a control, each replicated six times. Growth and yield parameters, including germination rate, leaf number, flowering time, pod number, and pod weight, were recorded. While germination and early vegetative growth showed no significant response, BSFF application significantly increased pod number and pod weight. The results demonstrate the potential of BSFF as an environmentally sustainable biofertilizer that enhances soybean productivity and contributes to soil health, thereby supporting long-term agricultural sustainability in low-input systems.