expression analysis of k^+ transporter genes associated with salinity tolerance in grape

Molecular information of k^+ accumulation in grapes is strongly required. under salinity condition potassium transporters are inhibited by na^+. the aim of this study was to investigate the effects of salinity on the expression of k+ transporter genes in grape. based on the previous screening study on 18 grape genotypes, ‘h6’ and ‘gharashani’ (tolerant) and ‘shirazi’ and ‘ghezeluzum’ (sensitive) were selected. plants were treated with 50 mm nacl as a critical concentration that was not lethal for grapevine plants. interestingly, the expression of vvkup1, vvkup2 and vvk1.1 genes highly increased in leaves of sensitive genotypes compared to tolerant ones. also the expression of vvkup1 and vvkup2 genes were similar in the leaves of sensitive genotypes. there was a significant positive correlation (p<0.05) between the expression of k^+ transporters –vvkup1 and vvkup2- and the accumulation of na^+ in the leaves of sensitive genotypes. roots of all genotypes showed increase in expression of vvk1.1 under salinity. the findings highlighted a strong relationship between the accumulation of specific transcripts and the degree of stress tolerance.