Green biosynthesized silver nanoparticles using Acalypha wilkesiana extract control root-knot nematode

Nanoparticles nowadays are an effective control agent against most phytopathogens. However, there are many reports on their antimicrobial activity and little as a nematicide. In this study, green biosynthesis of silver nanoparticles (Ag NPs) using Acalypha wilkesiana aqueous leaf extract was achieved. X-ray diffraction patterns confirmed the crystalline structure with face-centred cubic (fcc), where is the size was nearly 20 nm. SEM images of the Ag NPs show the spherical shape and in the range from 10 to 30 nm. Various functional groups, capping, and stability agents were identified using Fourier transmission infrared spectroscopy (FTIR). The nematicidal activity of biosynthesized Ag NPs conc. 25, 50, and 100 mg/mL were evaluated in vitro against root-knot nematode (Meloidogyne incognita), egg hatching (6 days after) and movement after 24 and 48 h. The Ag NPs (100 mg/ml) application after 48 h was the most effective treatment that showed 53.3% of nematode mortality. Overall, the efficiency of bio-Ag NPs reduced the nematode activity, mortality, egg hatching, and movement of larvae. To our knowledge, this is the first report of nematicidal action of biosynthesized Ag NPs using A. wilkesiana aqueous extract, and it could be recommended to manage the plant-parasitic nematode as it is simple, stable, cost-effective and keep the environment safe. (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.