Foliar Application of Low Concentrations of Titanium Dioxide and Zinc Oxide Nanoparticles to the Common Sunflower under Field Conditions

Abstract

Nano-fertilisers have only recently been introduced to intensify plant production, and there still remains inadequate scientific knowledge on their plant-related effects. This paper therefore compares the effects of two nano-fertilisers on common sunflower production under field conditions. The benefits arising from the foliar application of micronutrient-based zinc oxide fertiliser were compared with those from the titanium dioxide plant-growth enhancer. Both the zinc oxide (ZnO) and titanium dioxide (TiO2) were delivered by foliar application in nano-size at a concentration of 2.6 mg·L−1. The foliar-applied nanoparticles (NPs) had good crystallinity and a mean size distribution under 30 nm. There were significant differences between these two experimental treatments in the leaf surfaces’ trichomes diversity, ratio, width, and length at the flower-bud development stage. Somewhat surprisingly, our results established that the ZnO-NPs treatment induced generally better sunflower physiological responses, while the TiO2-NPs primarily affected quantitative and nutritional parameters such as oil content and changed sunflower physiology to early maturation. There were no differences detected in titanium or zinc translocation or accumulation in the fully ripe sunflower seeds compared to the experimental controls, and our positive results therefore encourage further nano-fertiliser research.

Nanotechnology in plants: recent advances and challenges

“…92,105 Among recent examples, ZnO NPs and TiO 2 NPs were delivered by foliar application under field conditions in sunflower. 106 ZnO NP (17.3 nm mean size) treatment induced better physiological responses and conferred greater resistance to both drought and water-logging, while TiO 2 NPs (20-30 nm size) positively affected quantitative and nutritional parameters such as oil content and changed sunflower physiology to promote early maturation. 106 Soil and foliar application of ZnO NPs (30 nm mean size) and Fe www.soci.org DF Fiol et al…”

Biotemplated Synthesis of Titanium Oxide Nanoparticles in the Presence of Root Extract of Kniphofia schemperi and Its Application for Dye Sensitized Solar Cells

“…International Journal of Photoenergy with scan wavelength of 200 to 800 nm [14][15][16]. The morphology and microstructure of biosynthesized TiO 2 NPs were observed using field emission SEM-EDS (FE-SEM, JEOL-JSM 6500F, Japan) and high-resolution TEM (HRTEM, Tecnai F20 G2, Philips, Netherlands).…”

“…Compared to the very low absorption of the reference TiO 2 NPs, our TiO 2 NPs biosynthesized at different volume ratios exhibited a slight shift of the absorption edge towards the visible region due to their smaller size. The energy bandgaps of the biosynthesized TiO 2 NPs were estimated using the Tauc's plot method technique [15]. With the Tauc plot in terms of the ðαhνÞ 2 versus hν in Figure 9(b), the energy bandgaps (E g )f TiO 2 NPs were determined to be 3.35, 3.33, and 3.36 eV for the different volume ratios of TiO 2 synthesized within a volume ratio of 2 : 3, 1 : 1, and 3 : 2, respectively.…”

Green Synthesis of Zinc Oxide Nanoparticles: Fortification for Rice Grain Yield and Nutrients Uptake Enhancement

“…The micronutrients assessed in fertilizers are increasingly efficient in the agro-sector both quantitatively and qualitatively through the use of nanoparticles (less than 100 nm). Via these modifications, it is expected to produce positive results in terms of both plant growth and the micronutrients assessed in fertilizers, which are increasingly quantitatively and qualitatively efficient in the agro-sector [ 16 , 17 ]. In particular, foliar treatment with Zn fertilizers as ZnO NPs achieved promising results in improving the nutritional efficiency of the grain under both natural and stress conditions [ 18 ], increasing the yield of grains, the amount of spikelets per spike, the number of tillers per hill, and the weight of 1000 grains [ 19 , 20 ].…”