Table II.
Relative contents of Al and selected mineral nutrients in cell walls of maize root tips (0–1.5 mm)
| Exposure Time | Al Treatment | Relative Contents
|
|||||
|---|---|---|---|---|---|---|---|
| Al | P | S | K | Ca | Zn | ||
| h | μm | counts s−1 | |||||
| 0 | 0 | NDa | 17 ± 2 | 12 ± 2 | 0.4 ± 0.0 | 1.2 ± 0.5 | 1.2 ± 0.6 |
| 4 | 0 | ND | 22 ± 4 | 11 ± 1 | ND | 1.3 ± 0.1 | ND |
| 4 | 20 | 2.8 ± 1.8 | 12 ± 7 | 5.4 ± 2.4 | 3.2 ± 1.1 | 1.3 ± 0.5 | 0.7 ± 0.2 |
| 24 | 0 | ND | 18 ± 3 | 8.1 ± 2.9 | ND | 3.7 ± 0.1 | ND |
| 24 | 20 | ND | 7.1 ± 4.2 | 9.2 ± 4.2 | ND | ND | ND |
| 24b | 20 | ND | 13 ± 6 | 7.5 ± 3.8 | 23 ± 8 | 2.5 ± 1.0 | ND |
| 24c | 20 | ND | 16 ± 10 | 11 ± 6 | 105 ± 52 | 6.0 ± 2.8 | ND |
Plants were exposed for different times to nutrient solutions containing 0 (control) or 20 μm Al. If not indicated otherwise, the values are from glutaraldehyde-fixed samples. Values are given as means ± sd; n ≥ 4 for control and n ≥ 9 for Al-treated plants.
a
ND, Not detected.
b
Samples prepared by freeze-substitution.
c
Samples prepared by pyroantimoniate staining.