FLOWER FORMATION IN EUCHARIS AMAZONICA LINDEN EX PLANCHON

Flower formation in Eucharis amazonica Linden ex Planchon is induced when plants are exposed to 4 weeks at 27°C followed by 21°C. Eighty to 100% of the plants flower after 90 to 95 days at 21°C.

The bulb has one terminal growing tip.
At 21°C it changes from vegetative to generative, and a vegetative lateral growing tip is being formed.
All flowers of the inflorescence (two helicoid cymes) are completed after 28 days at 21°C. The vegetative lateral growing tip is morphologically complete after 19 days at 21°C. After 56 days at 21°C it can be induced to flower formation, if plants are exposed again to 4 weeks at 27°C, followed by 21°C. After 90 to 95 days at 21°C the plants will then flower again.
Generally, a temperature drop of about 6°C is a prerequisite for floral induction.
The low temperature should, however, not be too low (13°C), to avoid growth arrest.
Temperature-controlled flower formation in Eucharis amazonica allows the production of 4 cut flowers per plant per one year.

Flower formation is also induced after drying out to wilting and then rewatering the plants.
As a result, only 25% of the plants flower, 95 days after withholding water.
Stress is thought to be the common cause for the induction of flower formation after a change in temperature or after wilting.

IV International Symposium on Flower Bulbs

J. van Bragt, W. Luiten, P.A. Sprenkels, C.J. Keijzer

https://doi.org/10.17660/ActaHortic.1986.177.21