THE INFLUENCE OF STORAGE TEMPERATURE AND 2-CHLOROETHYL-PHOSPHONIC ACID (ETHEPHON) ON SHOOT ELONGATION AND FLOWERING IN TULIPS

Five-degree precooling of bulbs of "Paul Richter" and "Apeldoorn" in dry and wet storage conditions was compared.
No significant difference in shoot growth and flowering date was obtained after dry and wet precooling.

Some days (3–6) high temperature treatment (15 or 21°C) during or after precooling promoted shoot growth and reduced the forcing time, while prolonged high-temperature treatment retarded shoot growth, induced bud blasting and formation of flowers with white/green tips of the perianths. "Paul Richter" was more sensitive to high-temperature treatment than "Apeldoorn".

Treatment of bulbs with ethephon before planting reduced shoot growth and promoted bud blast.
At 250–500 ppm many flowers had white/green perianths (especially "Paul Richter") and abnormal leaves.
At 1000–2000 ppm ethephon the shoots were almost entirely without flowers (bud blast)

II International Symposium on Flower Bulbs

R. Moe, A. Koller Hagness

https://doi.org/10.17660/ActaHortic.1975.47.44