فهرست نشریات علمی دسترسی آزاد ایران

The effect of cholorate different concentrations between 0 to 100 µM on high affinity transport system activity using Arabidopsis thaliana mutants atnrt2.1, atnrt2.4 and chl1-5 and transformants in NRT2.1 gene in two research sections was studied. In the first section, two pH 6 and 6.5 were used in a medium of free nitrate. 3 different nitrate and cholorate concentrations including 0, 25 and 50 µM with pH 6.5 were selected during second section. All seeds were cultured on solid medium and maintained in a controlled-environment condition. After 7 days, in order to gain further insight into the role of nitrate high affinity transport system, percentage of full expanded leaflets as indicator of high affinity transport system activity was investigated. The results showed the superiority of atnrt2.1 mutant in comparison with the other genotypes, especially on higher concentrations of cholorate, either with nitrate or without nitrate. Deregulation of AtNRT2.4 and AtCHL1 genes was not conducive to significant resistance. On the other hand, upregulation of NpNRT2.1 gene in atnrt2.1 mutant decreased percentage of full expanded leaflets. Based on these results, it was confirmed that AtNRT2.1 gene had key and important role in nitrate uptake by high affinity transport system.