Articles
POST-HARVEST WATER RELATIONS OF LEUCADENDRON CV. SILVAN RED
Silvan Red (Ld. laureolum x Ld. salignum) fell from six to four and a half weeks, after exposure to a transient water stress, in the form of strong drying conditions for 30 hr, during which leaf water potentials fell to -3200 kPa.
Vase life was identified by the appearance of localised desiccation of leaves, starting from the tips and extending towards the leaf-base.
Ion leakage from the leaves, as a whole, was not detected, but localised leakage of solutes within leaves may have occurred and not been detected.
Leaf water relations, were similar for both treatments, with turgor declining from 1300 kPa, initially, to zero by about day 37, and solute potential increasing from -1450 kPa, initially, to -1150 kPa by day 37, indicating loss of solutes.
The latter was consistent with loss of dry weight.
Transpiration of stressed stems fluctuated in the experiment but fell to a level, similar to the controls and after 45 days had fallen steadily to one fifth of the initial value.
Leaf turgor in cv.
Silvan Red can be expected to respond to various treatments e.g. pulsing solutions, to improve food supply, but it is not known whether such treatments will alleviate the effects of severe transient stresses on vase life.