The Effect of Treated Seeds with Normal and Dye-sensitized TiO2 Nanoparticles on the Elements Absorption and the Enzymatic Activity

Increasing the production rate became considerable for farmers in various ways. Modern technologies, such as biotechnology and nanotechnology could play an important role in increasing the production and improving the quality of agricultural products. Research into the direct application of nanotechnology into agriculture is set to increase in the future. One of the most remarkable plant growth factors is its nutrition. Titanium plays a beneficial role in increasing and stimulating plants growth. Titanium's usage in nutrition solution or spraying on the plant will increase the biomass and growth of different plant species. With respect to Nano technology enhancement in recent years the application of nano-particles is increasing. All the positive effects of titanium dioxide depend on its ability to absorb light and the main disadvantages of this combination are the low ability to absorb visible light from the sun and absorbing more UV light.  It is possible to improve its effectiveness due to the high proportion of sunlight in the visible range by absorbing the visible light of nano-particles. To achieve this goal a layer of color will be added on the surface of the nanoparticles, which is called the nanoparticle sensitization by color. Due to the absorption of light by titanium dioxide nano-particles, especially ultraviolet radiation, it is assumed that the creation of a color layer on these nano-particles increases the antibacterial and fungal properties of these nanoparticles. As a result, the goal of this experiment is to investigate the possible increase in light absorption and increase the yield of the sorghum plant by titanium dioxide nano-particles of Dye-Sensitized, which, some of the parameters were investigated by treating the seeds of the plant with both nanoparticles. This research was performed in three replications in a completely randomized design with factorial arrangement and with 12 treatments containing 6 concentrations of titanium dioxide nano-particles (0, 1, 10, 50, 100 and 500 mg.L-1), 6 concentration of titanium dioxide nanoparticles of Dye-Sensitized (0, 1, 10, 50, 100 and 500 mg.L-1). Fresh and dry weight of plants, plant nutrients content (Phosphorus, Potassium, Manganese, and Zinc), activity of ascorbate peroxidase and guaiacol peroxidase and chlorophyll content parameters  have been measured. The saffron compounds have significant peaks in the UV-Vis spectrum. The spectrum of titanium dioxide nanoparticles has a specific peak in the ultraviolet range (Area between wavelengths of 200-400 nm) however there is no trace of absorption in visible areas. The spectrum of the saffron solution has two identifiable peaks at 328 and 258 nm, and a double peak at 466 and 442 nm. The observed peak at 258 nm is related to the combination of Picrocrocin, which is the same colorless bitter substance found in saffron. The dual peaks range between 400-500 nm and the peak appearing at 328 nm are related to the carotenoids found in saffron. Crocin also has similar peaks which are likely to be overlapping with trans-isomeric peaks and not separable. The Spectrum of titanium dioxide nano-particles covered with saffron color also represents two peaks at 322 and 260 nm, and a peak at 430 nm with a specific shoulder at 458 nm. What comes from the comparison of two saffron peaks alone and saffron coated on titanium dioxide nano-particles is that the Crocin molecules contained in saffron are attached to nano-particles. According to the results, dry weight and enzymatic activity of Guaiacol peroxide and Ascorbate peroxide showed a significant increase compared to the control and had the highest performance respectively at concentrations of 10, 100 and 500 mg.L-1of titanium dioxide nano-particles of Dye-Sensitized, and showed 1.25, 2.7 and 3.28 fold. The amount of plant nutrients such as phosphorus, potassium, manganese, and zinc at concentrations of 10, 100, 500 and 50 mg.L-1titanium dioxide nanoparticles of Dye-Sensitized had a 72.34, 42.85, 73.95 and 28.17 percent increase, except fresh weight and chlorophyll a. Chlorophyll a at a concentration of 500 mg.L-1of both nano-particles showed the highest amount, but the fresh weight, unlike other parameters, showed the best performance with normal nanoparticles. It seems that these nano-particles, by coloring, intensify light-related reactions compared to normal nano-particles, which results in better performance.