Table 2.
Root type | Root zone | Conductivity |
||
Control | HgCl2 | HgCl2/DTT | ||
Seminal | Transition | 100a (6.1 ± 3.3) | 4.5 ± 0.8b | 91.9 ± 25.1a |
Mature | 100a (1.2 ± 0.6) | 16.6 ± 3.0c | 111.2 ± 27.3a | |
Lateral root | 100a (8.4 ± 3.3) | 10.3 ± 3.5c | 106.6 ± 14.7a | |
Adventitious | Transition | 100a (21.1 ± 13.3) | 5.6 ± 2.0b | 46.9 ± 13.3d |
Conductivity was determined through the cell pressure probe. Cortical cells were analysed in three zones of seminal roots and in the transition zone of adventitious roots. Roots were analysed in normal growth medium (‘control’) and after transient (5 min) exposure to 50 μM HgCl2, without (‘HgCl2’) or with subsequent recovery (15 min) in 5 mM DTT (‘HgCl2/DTT’). Results are means ±SD of 5–14 cell analyses expressed as a percentage of the control. Hydraulic conductivity (10−5 m s−1 MPa−1) of cells of control plants is given in parenthesis; for statistical analysis of these values see Fig. 2D. Different superscripts indicate significant differences between treatments (P<0.05).