|Author: ||A. H. Halevy|
Wilting and lack of full opening, which are indications of water stress, are the most common reasons for termination of vase life of cut flowers.
Water potential of cut flowers declines with time as well as water uptake, water loss and water conductivity in the flower stem.
The decline in water conductivity is one of the main reasons for impaired water balance.
The reason for this phenomenon is not yet known.
Bacterial contamination contributes to, but is not the sole reason for this decline.
Both cytokinins and abscisic acid improve water balance of cut flowers, the first by promoting water uptake and the second by reducing water loss.
Sucrose at high concentration (5–40%) supplied as a short term treatment to cut flowers accumulates in the cells, increasing the osmotic potential of the petals.
This enables the treated flowers to absorb much more water compared to untreated flowers.
This osmotic adjustment is greater in the petals than in the foliage leaves of the same stem.
Leaves of various species and even cultivars differ greatly in their ability to adjust osmotically.
Several metabolic sugars are equally effective in this response but the non-metabolic sugar manitol is not effective.
Osmotic adjustment has also been observed with several mineral salts like KCl, KNO3 and NH4NO3.
Download Adobe Acrobat Reader (free software to read PDF files)
URL www.actahort.org Hosted by KU Leuven