Aims: In this work we assessed Fe2O3 nanoparticles with bulk Fe2O3 for possible phytotoxicity and stimulative effects on wheat seed germination and early growth stage. Methodology: The treatments in the experiment were five concentrations of bulk (100, 500, 1000, 5000 and 10000 ppm) and five concentrations of nanosized Fe2O3 (100, 500, 1000, 5000 and 10000 ppm) and an untreated control. Germination tests were performed according to the rule issued by ISTA. Analysis of variance (ANOVA) was performed between treatment samples. The information was analyzed using MSTAT-C computer software. Means compared by multiple range Duncan test and a 95% significance level (p < 0.05) was employed for all comparisons. Results: Results showed that exposure of seeds to 100 ppm iron oxide nanoparticles indicated the greatest germination rate (by 41% more than control group) related to other treatments. Increasing nanoparticles concentration above 100 ppm reduced seed germination rate. It has not found any significant effects by bulk and nanoparticles on elongation of shoot, root and seedling of wheat. Application of 100 ppm concentration of nanosized Fe2O3 reduced mean germination time (MGT) by 38.5% in comparison to the control, while 100 ppm concentration of bulk Fe2O3 did not decrease MGT in comparison with the control. The highest root biomass was achieved from concentration of 100 ppm nano- Fe2O3, but an increased concentrations of nanoparticles Fe2O3 significantly reduced root weight. Nevertheless, on the basis of these results it is highly recommended that the influence of low dose nanomaterial be assessed in order to encourage seed germination and seedling growth.

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