Effect of green-synthesized silver nanoparticles (AgNPs) on the growth performance and chlorophyll content of cowpea (Vigna unguiculata L. Walp.)

Silver nanoparticles (AgNPs) have been studied for their potential effects on various plant varieties including cowpea. This study investigates the impact of different concentrations of green-synthesized AgNPs on the growth parameters such as leaf length, leaf area, shoot height, and chlorophyll accumulation of Vigna unguiculata L. Walp. In this study, seeds of cowpea variety 10K-843-2 were planted in soil pre-treated with bio synthesized AgNPs at 25%, 50%, and 75% while water served as control. Result showed that plants exposed to 75% concentration of AgNPs gave the highest (p≤0.05) leaf width, shoot height, leaf length and leaf area, numbers of pods and relative water content which was statistically different from other plants treated with 25%, and 50% AgNPs respectively at (p≤0.05). The highest chlorophyll accumulation was observed in cowpea exposed to 50% green- synthesized AgNPs. The lowest result for all the parameters was however observed in the plants treated with no AgNPs (i.e. control 0%). These findings provide insight into the effects of AgNPs on cowpea morphology and its photosynthetic pigments accumulation.