Definition of indicators of senescence in the rose: effect of the application of plant hormones.
Barthe, P.; Vaillant, V.; Gudin, S.;
Acta Horticulturae Year: 1991 Issue: No. 298 Pages: 61-68 Ref: 13 ref.
1991
บทคัดย่อ
Greenhouse-grown roses (Rosa hybrida, cv. Royalty) were harvested at the pre-opening stage and kept at 4 deg C for 24 h. The stems were then cut to a uniform length, each with the same number of leaves and placed in tap water. The 5 external petals were discarded and the water content, water potential and pH, osmolarity and conductivity of the cell sap of the following 5 petals were measured. In a further experiment, stems were either fed during their vase life with ABA or cytokinin (10-5M) or sprayed with ABA (10-5 or 10-3M) or cytokinin (10-3M) before placing in a vase. During the first 3 days of vase life, the FW/DW ratio increased sharply, water potential increased, osmolarity decreased markedly and conductivity decreased gradually. After 3 days, the FW/DW ratio decreased rapidly, water potential decreased gradually and osmolarity and conductivity increased sharply. The pH of the cell sap increased continuously during vase life reaching a steady state in late senescence. These 2 stages are related to (1) flower bud growth and development to full aging (first 3 days) followed by (2) maturation, senescence and wilting (from 3 days onwards). The presence of ABA or cytokinin in the holding water shortened the vase life of cut roses and resulted in a lower FW/DW ratio and higher pH, osmolarity and conductivity at the end of 9 or 10 days compared with untreated control roses. Foliar spraying with ABA or cytokinin delayed wilting and senescence, increased the vase life and resulted in higher FW/DW ratio and lower pH, osmolarity and conductivity after 10 days compared with control roses. It is concluded that the measured parameters are good indicators of senescence.