Soil Augmentation with Moringa oleifera Lam. Leaf Materials for Assessment of Pod Yield, Nitrate Reductase Activity and Proximate Fractions of Bambara Groundnut (Vigna subterranea (L.) Verdc.

Application of dry ground leaves of Moringa oleifera (Lam.) as soil nutrient augment for the productive assessment of seven accessions of bambara groundnut (Vigna subterranea (L.) Verdc.) was studied. The experimental pots (containing 4 kg of soil) were treated with 0 g (control), 10 g, 20 g and 35 g of dry powdered leaves in three replicates, arranged as completely randomised block design. Data collected include percent germination, number of days to flower bud formation, number of flower buds and flowers formed, number of pods produced per plant and 100-pod fresh and dry weights. Other parameters analyzed were acid phosphatase activity, nitrate reductase activity and proximate contents of harvested pods. One hundred percent germination was recorded for bambara seeds sown in soils augmented with M. oleifera in all accessions assessed. Early flower bud formation was observed in five accessions. Fresh and dry weights of 100-pod had no significant difference among the treatments in all the accessions studied. Higher numbers of pods were recorded for plants grown in the augmented soils with M. oleifera. Significantly lower values of acid phosphatase activity (µmol/min/g), and higher values of nitrate reductase activity (µmol/min/g) were observed in accessions grown in augmented soils. Values for proximate content were observed to increase with the proportions of M. oleifera employed. Furthermore, an increase in pod size was observed in accession (TVSU-466) grown in soil amended with 35 g dry ground powdered leaves of M. oleifera. The result obtained in this study demonstrated that using dry ground leaves of M. oleifera as soil augment is a good soil enhancer and has the capacity to boost plant yield.