Investigation of relative expression of some genes related to iron-induced toxicity in two varieties of Rice (Oryza sativa)

Iron toxicity lead to increasing of free oxygen radicals, oxidative stresses and sever yield reduction of Rice. One of the plant responses for physiochemical and biochemical regulation to stresses is change of antioxidant enzyme contents. In this study the effect of five treatments of iron (Fe-EDTA) (0, 100, 250, 400 and 500 mg/li-1) on relative expression of glutaredoxin (GRX), thioredoxin (TRX), peroxiredoxin (PRX) and catalase (CAT) genes of IR64 (susceptible) and Pokkali (tolerant) genotypes of Rice in Yoshida hydroponic media by Real time-PCR technique investigated. The results showed that the relative expression level of CAT gene in different levels of iron in Pokkali genotype was higher than IR64 genotype. The relative expression level of PRX in IR64 genotype in all of the levels was similar. The relative expression level of TRX in Pokkali genotype was not significant. The relative expression level of GRX in the most of stress levels in Pokkali genotype was higher than IR64 genotype. Low level iron result in increasing of relative expression level of CAT, GRX and TRX in IR64 genotype. But with increasing level of iron was not significant change in expression of genes. Also in the most of the iron level relative expression of genes in Pokkali was higher than IR64. Probably lose of change in gene expression levels in high level iron and low gene expression in IR64 is one of the reasons of its susceptibility to iron stress.