4.2. Water relations
A rapid decrease of water uptake was found and a less rapid decrease in transpiration. This resulted in net water loss from the flowering stem. The net water loss was virtually limited to the stem, with some stem segments losing more water than others. In experiments carried out in summer, stem bending was related to the net loss of water from the parts of the stem where bending occurred (about 12 cm below the floral head). Bending was prevented by covering the stems with a plastic bag, which prevented the loss of water from the stems. These data strongly suggest that water loss in specific stem segments is one of the causes of stem bending.