Fig 1.
(A) Germination phenotype of oat seeds in the control (water), CaCl2 (10 mM), NaCl (150 mM), and NaCl (150 mM) + CaCl2 (10 mM) treatments on day 7 day after NaCl stress. (B) The morphological changes of oat plants in the control (nutrient solution), CaCl2 (10 mM), NaCl (300 mM), and NaCl (300 mM) + CaCl2 (10 mM) treatments on the day of NaCl stress (1) and on days 3 (2), 6 (3), 9 (4), 12 (5), and 15 (6) after NaCl stress. Each treatment of the pictures is the 3 replicates.
Table 1.
Germination rate, electrolytic leakages of oat seedlings in the control (water), CaCl2 (10 mM), NaCl (150 mM), and NaCl (150 mM) + CaCl2 (10 mM) treatments on day 7 after NaCl stress and aboveground dry weight, Na+ and Cl- content, and electrolytic leakages of oat leaves in the control (nutrient solution), CaCl2 (10 mM), NaCl (300 mM), and NaCl (300 mM) + CaCl2 (10 mM) treatments on day 15 after NaCl stress.
Fig 2.
The curves of PF transients of oat leaves in the NaCl treatment and the NaCl treatment with CaCl2 amendment on the day of NaCl stress and on days 3, 6, 9, 12, and 15 of NaCl stress.
(A, B, C) PF intensity (rel.u.), normalized transients and ΔVt curves in single NaCl treatment. (D, E, F) PF intensity (rel.u.), normalized transients and ΔVt curves in the NaCl treatment with CaCl2 amendment. The signals were plotted on a logarithmic time scale (JIP Time). Each value of the curves is the average of 3 replicates.
Fig 3.
The curves of the K and L band in NaCl treatment and NaCl treatment with CaCl2 amendment on the day of NaCl stress and on days 3, 6, 9, 12, and 15 of NaCl stress.
(A, B, E, F) the curves of the K-band and L-band in NaCl treatment. (C, D, G, H) the curves of the K-band and L-band in NaCl treatment added CaCl2. The signals were plotted on a logarithmic time scale (JIP Time). Each value of the curves is the average of 3 replicates.
Fig 4.
T The parameters of PF OJIP transients of oat leaves in the NaCl treatment and NaCl treatment with CaCl2 amendment on the day of NaCl stress and on days 3, 6, 9, 12, and 15 of NaCl stress.
(A) PIABS, performance index. (B) ABS/RC, absorption of antenna chlorophyll per PSII reaction center. (C) FV/FM, potential maximum photosynthetic capacity. (D) ETO/TRO, efficiency of electron movement. Each parameter is the average of 3 replicates.
Fig 5.
DF induction curves of oat leaves in the NaCl treatment and NaCl treatment with CaCl2 amendment on the day of NaCl stress and on days 3, 6, 9, 12, and 15 of NaCl stress.
(A, B) The absolute values in NaCl treatment and NaCl treatment added CaCl2. (C, D) The normalized curves in the NaCl treatment and NaCl treatment with CaCl2 amendment. The D0 was the initial value, the peak I1 was the value at 3 ms, the I2 was the value at 100ms, the D2 was the final value of plateau. The signals were plotted on a logarithmic time scale (JIP Time). Each value of the curves is the average of 3 replicates.
Fig 6.
The modulated 820-nm reflection kinetics (MR/MRO) of oat leaves in NaCl treatment and NaCl treatment with CaCl2 amendment on the day of NaCl stress and on days 3, 6, 9, 12, and 15 of NaCl stress.
(A)The MR/MRO curves in the NaCl treatment. (B) The MR/MRO curves in NaCl treatment added CaCl2. The signals were plotted on a logarithmic time scale (JIP Time). Each value of the curves is the average of 3 replicates.