Table V.
A comparative HPLC separation of organic acid (based on identical retention time to standard references) and concentration in the fractions with molecular mass ≤10 kD of Ni-S and Ni-D foliage from young pecan seedling trees
| Organic Acids
|
Retention Time
|
Concentration X ± sda
|
|
|---|---|---|---|
| Ni-D | Ni-S | ||
| min | μm/mL | ||
| Oxalic acid | 1.18 | 6.56 ± 0.94a | 2.68 ± 0.26b |
| Tartaric acid | 1.32 | ≤0.50a | ≤0.50a |
| Formic acid | 1.45 | ≤0.50a | ≤0.50a |
| Malic acid | 1.86 | ≤0.50a | ≤0.50a |
| Lactic acid | 2.25 | 29.80 ± 0.22a | 9.27 ± 1.77b |
| Acetic acid | 2.60 | ≤0.50a | ≤0.50a |
| Diglycolic acid | 2.86 | 2.33 ± 0.88a | 2.16 ± 0.44a |
| Maleic acid | 3.74 | ≤0.50b | 1.83 ± 0.33a |
| Citric acid | 3.95 | ≤0.50b | 3.33 ± 0.33a |
a
Means (±sd) followed by the same letter are not significantly different (t test; P ≤ 0.05).