Table 1

Primer sequences"

Table 2

Maize NHX gene information"

Fig. 1

Phylogenetic tree of NHX gene family in Arabidopsis thaliana and maize (A) and ZmNHX7 branched protein structure (B)"

Fig. 2

Expression analysis of ZmNHX7 gene in different tissues of maize by real-time fluorescence quantitative PCR V1: the first leaf of maize was fully expanded; V7: the seventh leaf of maize was fully expanded; R2: grain formation period. The error bar shows the standard deviation of three biological replicates, the relative expression level in root (V1) was used as the control."

Fig. 3

Induced expression of ZmNHX7 gene A: analysis of the expression level of ZmNHX7 after treatment with different concentrations of LiCl for 5 hours; B: analysis of the expression level of ZmNHX7 after treatment with different concentrations of NaCl for 5 hours. error bars represent standard errors of three independent repetitions; * and **: the relative expression of ZmNHX7 under different concentrations of ion stress is significantly different from the content at the 0.05 and 0.01 probability levels, respectively."

Fig. 4

Subcellular localization of ZmNHX7 A: localization of YFP fluorescence in tobacco leaves; B: localization of ZmNHX7-YFP fluorescence in tobacco leaves; C: localization of ZmNHX7-YFP and marker fluorescence in tobacco leaves."

Fig. 5

Identification of the transfer and expression of ZmNHX7 by PCR A: RT-PCR was used to verify the transcription of AtNHX8 gene in WT and nhx8; B: expression of ZmNHX7 gene in different Arabidopsis lines; C: transcriptional expression of ZmNHX7 gene in different Arabidopsis lines. M: D2000 plus DNA marker."

Fig. 6

Phenotype and fresh weight of different Arabidopsis strains A: germination and subsequent growth of wild type, nhx8 and COM1-COM4 plants under MS agar medium and MS medium containing 5 or 15 mmol L-1 LiCl, or 75 mmol L-1 NaCl. B: the fresh weight of wild type, nhx8 and COM1-COM4 after seven days of growth on medium containing ionic stress (the data are shown as mean ± SD, n = 20. Bars superscripted by different capitals are significantly different at P < 0.01 within a treatment)."

Fig. 7

Arabidopsis root length and data statistics A: root length phenotype of WT, nhx8, COM1, and COM4 on MS medium containing 0, 5, 10 mmol L-1 LiCl, and 50, 100 mmol L-1 NaCl. B: the root length of WT, nhx8, COM1, and COM4 after seven days of growth on medium containing ionic stress (The data are shown as mean ± SD, n = 10. Bars superscripted by different capitals are significantly different at the P < 0.01 within a treatment)."