EFFECT OF BIOSYNTHESIZED ZNO NANOPARTICLES DERIVED FROM Jatropha tajonensis ON THE YIELD OF BAMBARA GROUNDNUT (Vigna subterranean L.)

Bambara groundnut is a resilient crop to poor and acidic soils and it is a significant underutilized crop with vital nutritional content. This study explores the impact of biosynthesized Zinc Oxide (ZnO) nanoparticles derived from Jatropha tajonensis leaf extract on the growth and yield of two Bambara groundnut (Vigna subterranean L.) varieties, SUAN and SOKOTO. The biosynthesized ZnO nanoparticles were characterized using UV/VIS, FTIR, SEM, and XRD methods. Seeds sourced from the Botany Department of Joseph Sarwuan Tarka University, Makurdi, Benue State, were treated with ZnO nanoparticles at varying concentrations (20ppm, 40ppm, 60ppm, 80ppm, and 100ppm), alongside control treatments of salt and NPK fertilizer. Significant improvements (p<0.05) were observed in growth parameters such as plant height, number of leaves, leaf width, and stem diameter, though leaf length decreased significantly (p<0.05). The yield of the crop was not significantly affected (p>0.05). Optimal growth for SUAN was observed at different concentrations for various parameters, while SOKOTO showed peak improvements at 60ppm for plant height and 100ppm for other parameters. Yield parameters, including the number of flowers, pods per plant, pod length, pod weight, and seed weight, were maximized at 80ppm and 100ppm for both varieties. Consistency in the number of days to flowering and seeds per pod was noted across treatments. This study concludes that ZnO nanoparticles treatments significantly enhance most growth and yield parameters of Bambara groundnut compared to salt and fertilizer controls, recommending their use for improved cultivation outcomes.