Table 4 Analysis of variance and mean comparisons for the expression of four genes (ZmSOS1,ZmHKT1,ZmNHX1, andZmSKOR) responsible for Na⁺and/or K⁺uptake, transport and compartmentalization in the shoots and roots of maize plants grown under two salinity levels and treated with DCPTA at four rates of application

Source of variation	Relative expression (RQ) in shoots				Relative expression (RQ) in roots
Source of variation	ZmSOS1	ZmNHX1	ZmHKT1	ZmSKOR	ZmSOS1	ZmNHX1	ZmHKT1	ZmSKOR
NaCl (mM) (N)
0	1.94 ± 0.80b	2.10 ± 0.85b	1.62 ± 0.50b	1.61 ± 0.45a	1.70 ± 0.50b	1.17 ± 0.14b	0.95 ± 0.13b	1.38 ± 0.21a
150	4.72 ± 0.31a	6.20 ± 1.85a	3.27 ± 1.39a	1.51 ± 0.53a	2.88 ± 0.37a	2.35 ± 0.19a	2.09 ± 0.74a	0.98 ± 0.25b
DCPTA (μM) (D)
0	2.81 ± 1.86a	2.47 ± 1.58b	1.33 ± 0.37b	0.95 ± 0.14b	1.77 ± 0.78b	1.69 ± 0.68a	2.06 ± 1.05a	0.90 ± 0.25b
20	3.78 ± 1.01a	4.67 ± 2.03a	2.73 ± 0.90a	1.82 ± 0.26a	2.58 ± 0.45a	1.77 ± 0.58a	1.37 ± 0.53b	1.32 ± 0.27a
100	3.41 ± 1.60a	5.31 ± 2.97a	3.28 ± 1.58a	1.91 ± 0.19a	2.53 ± 0.70a	1.82 ± 0.66a	1.15 ± 0.29b	1.33 ± 0.17a
Significance
NaCl (mM) (N)	***	***	***	ns	***	***	***	***
DCPTA (μM) (D)	***	***	***	***	***	***	***	***
N × D	**	***	***	ns	*	ns	***	ns

ns, *, **, and ***: Not significant or significant atP ≤ 0.05, 0.01, and 0.001, respectively. The different letters within each column indicate significant differences according to Duncan’s multiple-range test (P = 0.05)