EFFECTS OF COLD TREATMENT ON ANTHESIS OF TULIP WITH SPECIAL REFERENCE TO POLLEN DEVELOPMENT

Bulbs of Tulipa gesneriana ‘Queen of Night’ at stage G3 were treated with low temperature at 4°C or 8°C for 0 to 10 weeks and then grown under forcing conditions in a greenhouse.
The developmental process of microspores with different low temperature treatments follows a similar developmental pattern, irrespective of the duration of low temperature.
Pollen remained at the uninucleate stage for a long time after planting, then rapidly developed into the binuclear stage about one week before anthesis and then into mature pollen.
Generally, the days from planting to anthesis decreased, while the percentage of stainable pollen and the floral stalk length increased with increasing chilling duration.
However, the flowering percentage declined in the bulbs treated at 4°C for 8 and 10 weeks.
Stainable pollen in all treatments ranged 70-90% at anthesis.
Treatment of the bulbs with a higher stainable pollen percentage at the time of anthesis resulted in longer floral stalks too.
This positive correlation suggests that the elongation of floral stalk induced by chilling probably affects the development of pollen and vice versa.

IX International Symposium on Flower Bulbs

R.Y. Xu, Y. Niimi, D.-S. Han, S. Kuwayama

elongation, flower stalk, blasting, uninucleate stage, chilling duration, Tulipa gesneriana

https://doi.org/10.17660/ActaHortic.2005.673.49