TRANSIENT WATER-STRESS AND PHOSPHOLIPID TURNOVER IN CARNATION FLOWERS

Transient water stress, followed by a recovery period, resulted in a decline in the longevity of cut carnation (Dianthus caryophyllus L., cv. White Sim) flowers. This was accompanied by a sharp decrease in the phospholipid content of the petal membranes. The content of 1,2-diacylglycerol in a plasma membrane enriched fraction, expressed as a fraction of total phospholipids, increased with water stress and decreased during recovery, as did the concentration of inositol 1,4,5-trisphosphate in the tissue water. These results suggest that water stress in carnation flowers causes the release of both of these putative secondary messengers. This may in turn lead to the induction of processes associated with accelerated senescence.