Table II.

Contribution of Pro and K+ to the altered solute content of lwr1 and lwr2

Agar
Benlwr1 ψwlwr2
−0.25−0.75−0.25−0.75−0.25−0.75
MPa
ψs100 (MPa)−0.428−0.661−0.502−0.803−0.396−0.503
Solute content (mm)a175270205328162206
Solute difference (mm)b3058−13−64
Pro100 (mm)c0.313.200.763.860.492.03
Pro difference (mm)0.450.660.18−1.17
% Solute differenced2102
K+100, (mm)e59108611365586
K+ difference (mm)229−4−22
% Solute differencef7502634
  • ψs100 (Fig. 5) was converted to solute concentration (mm) and used to calculate the difference in solute concentration between mutants and wild type at −0.25 and −0.75 MPa. Pro (Fig. 4) and K+ (Fig. 6) contents were adjusted to 100% RWC and used to calculate the difference in content of Pro and K+ relative to wild type. These values were then compared to the total difference in solute content between mutant and wild type to estimate the contributions of Pro and K+ to the altered solute content of the mutants.

  • a Total solute content at 100% RWC calculated using the equation: ψs = −RTC.

  • b Difference in total solute content at 100% RWC between the mutant and wild type (Ben); negative values for lwr2 indicate that wild-type solute content was greater than that of lwr2.

  • c Pro content at 100% RWC calculated from data in Figures 4 and 5; a correction for percent dry weight (≤4%) was applied to the Pro data.

  • d Percent of the total difference in solute content at 100% RWC that can be accounted for by altered Pro content.

  • e K+ content at 100% RWC calculated from data in Figures 5 and 6.

  • f Percent of the total difference in solute content at 100% RWC that can be accounted for by altered K+ content.