Table II.
Effects of microtubule-depolymerizing compounds on blue light-dependent H+ pumping in Vicia guard cell protoplasts
Trifluralin, oryzalin, and propyzamide were added to guard cell protoplasts at the indicated concentrations 30 min before illumination with a pulse of blue light. FC was added at 10 μm. Experiments repeated three times on different occasions gave similar inhibitions.
| Concentration | Magnitude | Rate | Rate (+FC) | |
|---|---|---|---|---|
| μm | nmol H+μg protein−1 | nmol H+ h−1μg protein−1 | ||
| Trifluralin | 0 | 0.192 (100) | 2.39 (100) | 3.87 (100) |
| 1 | 0.166 (86.5) | 2.18 (91.2) | 3.60 (93.0) | |
| 10 | 0.119 (62.0) | 1.63 (68.2) | 3.57 (92.2) | |
| Oryzalin | 0 | 0.129 (100) | 1.38 (100) | 3.08 (100) |
| 1 | 0.120 (93.0) | 1.33 (96.4) | 3.08 (100) | |
| 10 | 0.070 (54.1) | 0.72 (52.2) | 3.07 (99.7) | |
| Propyzamide | 0 | 0.130 (100) | 1.70 (100) | 2.01 (100) |
| 20 | 0.122 (93.8) | 1.60 (94.1) | 2.27 (112.9) | |
| 100 | 0.114 (87.7) | 1.33 (78.2) | 2.61 (129.9) |