Journal of Plant Process and Function

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Nanomaterials are considered as one of the most important innovations of modern science. Nanoparticles are highly reactive. These property are largely due to their size (from 1 to 100 nm), large surface area and high solubility. Among all the micronutrients, iron has the largest amount in plants. Iron is the catalytic component of many oxidization and redox enzymes and is needed for chlorophyll synthesis. In this study, iron oxide nanoparticles in six different concentrations (0, 5, 10, 20, 30 and 40 micromolar) and compelte Hogland nutrient medium (include fe-chelate) as control environment was given to Catharanthus roseus plant for 70 days. The results have shown that iron oxide nanoparticles significantly increased the leaf growth parameters and carbohydrate contents in comparison with control plants, but it had no effects on the amount of proline, antioxidants and the stomatal density of leaf. The highest amounts of leaf growth parameters was obtained in 30μl iron oxide nanoparticles and the lowest values of these parameters was found with 0μl iron oxide nanoparticles. The highest values of proline and antioxidants activity were measured in 0μl iron, since this concentration is considered as stress for plant. Therefore use of iron oxide nanoparticles fertilizer is recommended, because it reduce the harmful effects of chemical fertilizers into the environment.

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Sports grass is a suitable mixture of premium and resistant varieties of grass that has been widely accepted in many countries of the world for lawn work in parks and sports fields. Considering the role of nanotechnology in the production of plants, it is very important to investigate the effect of nanoparticles on the growth processes of grass. In this research, the effect of iron oxide nanoparticles on some morpho-physiological characteristics of sport grass was investigated. The iron element is very important due to its placement in the electron transport chain and its role in photosynthesis. This research was carried out in a completely randomized design with three replications in fully controlled conditions. Foliar spraying of iron oxide nanoparticles was investigated in three stages with different concentrations (zero, 50, 100, 200, and 400 ppm). The results of variance analysis showed that the effect of iron oxide nanoparticle foliar application on some morphological characteristics such as root length, plant dry weight, and plant density per unit area was significant. The results of the comparison of the average effect of different concentrations of iron oxide nanoparticles on the dry weight of sport grass plants indicated that the concentration of 100 ppm of this nanoparticle accounted for the highest amount of dry weight of the plant with 0.080 grams, also the effect of foliar spraying of this nanoparticle. All physiological traits (chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, anthocyanin, catalase antioxidant enzyme, guaiacol peroxidase antioxidant enzyme, and free radical inhibition percentage) were significant at the 1% level. Based on the results of this research, the application of different concentrations of iron nanoparticles had a favorable effect on the amounts of photosynthetic pigments and antioxidant enzymes, which can be suggested as a suitable elicitor to increase the growth of morphological parameters and increase the quality of physiological parameters in sport grass.