IMPACT OF BIO-FERTILIZER AND PHOSPHORUS FERTILIZER ON GROWTH AND YIELD OF BAMBARA GROUNDNUT [Vigna subterranea (L.) Verdc]

The use of inorganic fertilizer has become unsustainable due to high cost and environmental pollution caused by its continuous application and there is a need to formulate a sustainable and ecofriendly method of crop yield improvement. A field experiment was carried out to evaluate the effect of biofertilizer and inorganic phosphorous on the growth and yield of Bambara groundnut during the rainy seasons of 2021 and 2022 at the Teaching and Research farm, University of Ilorin, Nigeria. The experiment was laid in a randomized complete block design, replicated thrice and treatments consisted of three bio-fertilizer (Aspergillus niger (PSF3), Aspergillus flavus (PSF4), Penicillium sp. (PSF5); combination of bio-fertilizer and single super phosphate (PSF3+ P2O5 at 30 kg/ha, PSF4+ P2O5 at 30kg/ha, PSF5+ P2O5 at 30 kg/ha); P2O5 at 30 kg/ha; P2O5 at 60 kg/ha and control (zero fertilizer). Data were collected on growth parameters (petiole length, number of leaves, crop growth rate and net assimilation rate) and yield per hectare. Data collected were subjected to analysis of variance (ANOVA) and means were separated using Duncan new multiple range test at 5% probability level. The result indicated that there was significant effect (Ρ < 0.05) on vegetative growth of plots treated with the combination of bio-fertilizers and 30 kg ha-1 single super phosphate. The maximum yield obtained was 1582.8 kgha-1 produced by soil applied with P2O5 60 kg ha-1 and this was closely followed by plot applied with Aspergillus flavus (PSF4). Farmers are therefore encouraged to apply (PSF4) for the yield improvement of Bambara groundnut in this zone when there is scarcity of phosphate fertilizer.