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Sustainable agriculture necessitates the exploration of eco friendly materials to eradicate the pathogenic menace without causing any adverse and residual impact on the environment. Nanotechnology proposes the prodigious aptitude by developing the nanometric-materials to change the pathological scenario of seeds. In this study, zinc carbonate nanoparticles (NPs) of varying sizes (ZnC-1 NPs, ZnC-2 NPs and ZnC-3 NPs) were prepared in aqueous media under sonochemical conditions to visualize the size-dependedant antifungal potential of ZnC NP. Topo-morphological parametric details were achieved by TEM, SEM-EDS, XRD, IR and UV-visible spectroscopic techniques. In vitro suppression of pathogenic fungi of rice seeds by ZnC NPs revealed the size-dependent inhibition of mycelial growth of Fusarium fujikuroi. The nanopriming of rice seeds with ZnC-3 NPs at 150 µg/ml for 6 h caused significant reduction in seedling blight (82 ± 2%) and seed rot (81 ± 4%) relative to control, while seeds nanoprimed for 8 h resulted in augmentated percent germination (90 ± 2%), root length (13 ± 1.0 cm), shoot length (9.9 ± 0.6 cm), dry weight (0.076 ± 0.003 g) and overall vigor index (6.84 ± 0.5) when comparad to control. The enhanced internalization of zinc in ZnC-3 NPs primed seedlings, compared to hydroprimed seeds, provides the evidence for the role of nano zinc in promoting growth of nanoprimed seedlings. Inclusively, by conducting extensive field trials on rice, ZnC nanoforms can be endorsed as environmentally friendly antifungal agents and classified as “nanofungicides” in the agricultural sector.

Surface-modified zinc sulfide nanoparticles (ZnS NPs) were prepared and their zeta potentials modulated by the topological adsorption of Zn2+and S2−ions viathe common ion adsorption property of colloids to visualize the effect of surface charge on their antifungal potential. The in vitrosuppression of Fusarium verticillioidesby ZnS©-6 NPs (ζ= +20.04 mV) revealed the charge-dependent enhancement in their antifungal potential, indicating that electrostatic interactions are their interactive mode. Specifically, the variation in the zeta potential of the fungal hyphae was measured to range from ζ= −13.20 mV to ζ= −5.34 mV during contact with the positively charged ZnS NPs. The SEM-EDS analysis and staining of the treated hyphae confirmed the association of the nanoparticles on the external surface of the hyphae, disrupting their external structure, which resulted in the leakage of their intercellular proteins, and finally their death. Nanopriming of rice seeds with ZnS©-6 NPs at 48 μg mL−1for 8 h significantly reduced the seed rot (66.62%) and seedling blight (75.27%) to the maximum extent compared to carbendazim as the standard fungicide. The enhancement in seed invigorating factors, i.e., germination (47.82%), shoot length (68.03%), root length (51.46%), dry weight (39.86%) and vigor index (68.63%), was maximum at this concentration with respect to the hydroprimed seeds (control). The positively charged ZnS©-6 NPs supported 2.5-times higher nutritional Zn modulation in the treated seedlings compared to the hydroprimed rice seeds serving as the control. Overall, these results suggest that ZnS©-6 NPs are potential dual-targeting bio-assimilative and agro-compatible nanoplatforms for constraining the growth of F. verticillioidesin rice seeds with health invigorating effects.