Grass-Shaped Zinc Oxide Nanoparticles Synthesized by the Sol-Gel Process and Their Antagonistic Properties towards the Biotrophic Parasite, Meloidogyne incognita

Abstract

The presence of Meloidogyne spp., also known as root-knot nematodes, presents a significant danger to global agricultural progress. Since chemical nematicides have high levels of toxicity, it is imperative to develop environmentally friendly methods to manage root-knot nematodes. Nanotechnology is now the most progressive way to attract researchers due to its innovative quality in combating plant diseases. Our study focused on the sol-gel process to synthesize grass-shaped zinc oxide nanoparticles (G-ZnO NPs) and assess its nematicidal behavior against Meloidogyne incognita. Various concentrations (250, 500, 750, and 1000 ppm) of G-ZnO NPs were utilized to expose both the infectious stage (J2s) and egg masses of M. incognita. Laboratory results revealed that G-ZnO NPs showed toxicity to J2s with LC50 values of 1352.96, 969.64, and 621.53 ppm at 12, 24, and 36 hours, respectively, and the result was the inhibition of egg hatching in M. incognita. All three exposure periods were reported linked with the concentration strength of G-ZnO NPs. The pot experiment results exhibited that G-ZnO NPs significantly reduced the root-gall infection of chickpea plants under M. incognita attack. Compared with the untreated control, there was a significant improvement in plant growth attributes and physiological parameters as well, when distinct G-ZnO NP doses (250, 500, 750, and 1000 ppm) were applied. In the pot study, we noticed a reduction in the root-gall index with an increase in the concentration of G-ZnO NPs. The results confirmed that G-ZnO NPs have enormous potential in sustainable agriculture for controlling the root-knot nematode, M. incognita, in chickpea production.

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

“…The current study aimed to characterize and assess the effects of walnut-based greensynthesized ZnO NPs on cowpea plants that were artificially inoculated with the root-knot nematode, M. arenaria, and the root-rot fungus, M. phaseolina, concurrently. Although the antifungal and nematicidal activity of both chemically and biosynthesized ZnO nanoparticles has already been studied by various researchers [13,[27][28][29], the objective of this study is to promote environmentally friendly approaches that use fewer chemicals, are cost-effective, and manage diseases without harming the environment [30]. In the current study, various characterization procedures were applied to validate the purity and authenticity of the synthesized ZnO NPs.…”

“…The J2s showing movement or twisting were considered alive [68], while those that remained motionless and straight, even after being exposed to tap water and pricked with a needle, were considered dead [69]. Probit analysis was employed to determine the LC50 value for each treatment based on the concentration and percent mortality data [13]. The formula for calculating percent mortality is as follows:…”

“…The popularity of ZnO NPs can be attributed to their unique attributes, including precise targeting capabilities, heightened bioavailability owing to increased solubility and permeability, reduced required dosages, minimized dose-dependent toxicity, and controlled release mechanisms [7]. Several researchers have studied the antifungal activity of ZnO NPs synthesized through green synthesis [8][9][10], and it has become evident that ZnO NPs possess potential antifungal and nematicidal properties [11][12][13].…”