Table 2.
Contribution of inorganic anions to equimolarity with cations in the leaf
| Ionic concentration (mmol g–1 DW) | Equimolarity (%) | Contribution to equimolarity (%) | |||||
|---|---|---|---|---|---|---|---|
| Cations | Anions | Inorganic anions | Organic moleculesa | SO4 2–+PO4 3– | NO– | Cl– | |
| BS | 1.76±0.05 b | 0.58±0.09 b | 32.6±4.4 b | 67.4±4.4 a | 14.3±0.9 b | 17.1±3.4 a | 1.1±0.2 b |
| SP | 1.96±0.08 ab | 0.65±0.08 b | 32.7±3.6 b | 67.3±3.6 a | 24.3±1.9 a | 7.7±2.2 b | 0.7±0.05 b |
| N | 2.10±0.05 a | 0.72±0.06 b | 34.4±3.0 b | 65.6±3.0 a | 8.9±0.3 b | 25.0±2.9 a | 0.5±0.02 b |
| CL | 2.02±0.07 a | 1.49±0.04 a | 74.3±2.0 a | 25.7±2.0 b | 10.6±0.4 b | 0.8±0.1 b | 62.9±2.0 a |
| P-value | * | *** | *** | *** | *** | *** | *** |
Treatments consisted of the basal nutrient solution (BS) alone or supplemented with 5mM nitrate (N) or the sulphate+phosphate (SP) salt mixture containing the same cationic balance as in the CL and N treatments.
Anions and cations measured to calculate the data in the respective columns were: Cl–, NO3 –, SO4 2–, and PO4 3–anions; and K+, Ca2+, and Mg2+ cations.
Mean values ± SE, n=4–6. Levels of significance: *P≤0.05 and ***P<0.001. ‘Homogeneous group’ statistics was calculated through ANOVA test.
a Not measured: deduced from quantification of inorganic ions.