Effect of Bio-Stimulants Extracted from Moringa, Neem, Papaya and Bitter Leaves on the Nutritional and Bio-Active Composition of Aerial Yam (Dioscorea Bulbifera) Mini-Setts

The use of chemical agents or plant extracts on the exposed surfaces of the minisett to retard fungal, nematode and insect attack is a common practice amongst farmers. As a result, it is important to investigate the effects of these extract on the nutritional composition of yam crop, as they can negatively impact it. Therefore, the objective of this paper was to evaluate the effect of bio-stimulants extracted from Moringa (MT), Neem (NT), papaya (PT) and bitter leaves (BT) on the nutritional and bio-active composition of aerial yam (Dioscorea bulbifera) mini-setts using appropriate standard techniques. Data obtained show that some of the bioactive components in the Dioscorea bulbifera mature leaves grown with different treatments at 12 weeks were amino acids (essential): histidine 2.34- 6.26,% valine 2.63- 7.04% isoleucine 2.76- 7.3%, (non-essential): serine 1.26-3.36%, glycine 1.82-4.87%, alanine 3.62- 9.68%, vitamins: vitamin A 8.92- 27.59ppm, vitamin B12 0.46-1.44ppm, vitamin C 0.16-0.52ppm, minerals (macro): Phosphorus 0.37-5.92ppm, Calcium 0.31-5-09ppm, Magnesium 0.41-1.28ppm, (micro): Iron 8.47-135.02ppm/g, Zinc 5.21-83.09ppm/g, Manganese 5.65-90.01ppm/g and proximate composition; carbohydrate 56.67-85.82%, protein 6.80-21.05%, ash 2.28-7.06%, fibre 4.56-14.12%, fats 0.91-2.82% respectively. Results reveal that control plants had higher amino acid content and vitamin content whereas Neem extract treated plants had the highest mineral content. Pawpaw treatment was observed to selectively increase carbohydrate content of treated plants but did not increase other proximate constituents.