Work

Harnessing Walnut-Based Zinc Oxide Nanoparticles: A Sustainable Approach to Combat the Disease Complex of Meloidogyne arenaria and Macrophomina phaseolina in Cowpea

Year: 2024

Type: article

Abstract: The development of biosynthesized nanoparticles for effective management of plant diseases is a game changer in agriculture. This study focused on the nematicidal and antifungal capabilities of walnut leaf-based biosynthesized Zinc oxide nanoparticles (ZnO NPs) as sustainable choices for farmers while minimizing their environmental footprint. Due to their unique structure and properties, zinc oxide nanoparticles exhibit diverse applications, including antimicrobial, UV-blocking, and catalytic properties. The biosynthesized ZnO NPs were characterized and applied to mitigate the impact of simultaneous infection by Meloidogyne arenaria (root-knot nematode) and Macrophomina phaseolina (root-rot fungus) in cowpea plants. The characterization of ZnO NPs was carried out through various analytical techniques, including UV-visible spectrophotometry, powder-X ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX). The study confirmed the successful synthesis of ZnO NPs with a hexagonal wurtzite structure and exceptional purity. During in vitro treatment, ZnO NPs showed significant nematicidal and antifungal action. The mortality rate of M. arenaria juveniles and mycelial growth inhibition of M. phaseolina increased with rising ZnO NP concentration. SEM studies revealed physical damage to nematodes and structural distortions in fungal hyphae due to ZnO NP treatment. In infected cowpea plants, ZnO NPs significantly improved plant growth parameters, including plant length, fresh mass, and dry mass, especially at higher concentrations. Leghemoglobin content and the number of root nodules also increased after ZnO NP treatment. Additionally, ZnO NPs reduced gall formation and egg mass production by M. arenaria nematodes and effectively inhibited the growth of M. phaseolina in the roots. Furthermore, histochemical analyses demonstrated a reduction in oxidative stress, as indicated by decreased reactive oxygen species (ROS) and lipid peroxidation levels in ZnO NP-treated plants. These findings highlight the potential of green-synthesized ZnO NPs to manage disease complex in cowpea caused by simultaneous nematode and fungal infections.

Source: Plants

DOI: 10.3390/plants13131743

Authors: Mir Hussain, Ghazala Parveen, Aashaq Bhat, Zubair Reshi, Farid Ataya, Zaffar Handoo