Harnessing walnut-based zinc oxide nanoparticles: a sustainable approach to combat disease complex of Meloidogyne arenaria and Macrophomina phaseolina in Cowpea

Authors: HUSSAIN, AKHTAR - Aligarh Muslim University; PARVEEN, GHAZALA - Aligarh Muslim University; BHAT, AASHAQ - Saveetha Institute Of Medical And Technical Sciences; RESHI, ZUBAIR - Aligarh Muslim University; ATAYA, FARID - King Saud University; Handoo, Zafar

Submitted to: Plants
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/21/2024
Publication Date: 6/24/2024
Citation: Hussain, A.M., Parveen, G., Bhat, A.H., Reshi, Z.A., Ataya, F.S., Handoo, Z.A. 2024. Harnessing walnut-based zinc oxide nanoparticles: a sustainable approach to combat disease complex of Meloidogyne arenaria and Macrophomina phaseolina in Cowpea. Plants. 13(13):1743. https://doi.org/10.3390/plants13131743.
DOI: https://doi.org/10.3390/plants13131743

Interpretive Summary: Plant-parasitic nematodes are microscopic worms that feed on plants and cause an estimated ten billion dollars of crop losses each year in the United States and 100 billion dollars globally. Root-knot nematodes are an economically important group of plant-parasitic nematodes worldwide. Cowpea plants, an important food and forage crop, are susceptible to damage from root-knot-nematodes as well certain species of fungi. Chemicals originally found in walnuts were made in the laboratory and tested for their effect on these organisms. Application of these chemical significantly improved plant growth. These findings highlight the potential of green-synthesized chemicals as an eco-friendly and effective solution to manage diseases in cowpea caused by simultaneous nematode and fungal infections. This research will be used by scientists,diagnosticians, growers, action agencies, and extension agencies involved in nematode research and control.

Technical Abstract: Zinc oxide nanoparticles (ZnO NPs) exhibit diverse applications, including antimicrobial, UV-blocking, and catalytic properties, due to their unique structure and properties. This study focused on the characterization of zinc oxide nanoparticles (ZnO NPs) synthesized from Juglans regia leaves and their application in mitigating 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-XRD analysis, FT-IR spectroscopy, SEM-EDX analysis. The study confirmed the successful synthesis of ZnO NPs with a hexagonal wurtzite structure and exceptional purity. Under in vitro conditions, ZnO NPs exhibited significant nematicidal and antifungal activities. The mortality of M. arenaria juveniles increased with rising ZnO NP concentrations, and a similar trend was observed in the inhibition of M. phaseolina mycelial growth. SEM studies revealed physical d mage 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 levels of reactive oxygen species (ROS) and lipid peroxidation in ZnO NP-treated plants. These findings highlight the potential of green-synthesized ZnO NPs as an eco-friendly and effective solution to manage complex diseases in cowpea caused by simultaneous nematode and fungal infections.