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Are gibberellins capable of replacing the environmental flowering signal?
- , YOSSI BEN-TAL
- Israel journal of plant sciences 2000 v.48 no.3 pp. 205-215
- Aster (Asteraceae), Hypericum, Limonium, Phlox, Solidago, cut flowers, flowering, gibberellins, light intensity, photoperiod, temperature
- Flowering is a complex cascade of processes that occurs in response to environmental signals such as photoperiod, temperature, light intensity, and spectrum. Gibberellins (GAs) are known to be able to replace some of these signals and induce flowering. The degree of substitution is not consistent, and sometimes the same GA is very effective in one species and inhibitory in another. A group of scientists constructed synthetic, custom-made GAs that promoted flowering and did not affect elongation in a few species. These synthetic GAs were tried on several long-day (LD) commercial cut flowers in order to enhance blooming. It was found that inaster, phlox, and limonium, all quantitative LD plants, endo-16,17-dihydro-GA<SUB>5</SUB> wasable to enhance flowering. In solidago and hypericum, mandatory LD plants, this compound could not replace the LD requirement and blooming date was similar to control plants in solidago and marginally enhanced in hypericum. On the other hand, GA<SUB>3</SUB> enhanced flowering in solidago but delayed blooming in hypericum. The reasons for different patterns of influence in different species are discussed.