ISHS Acta Horticulturae 325: VI International Symposium on Flower Bulbs
EFFECTS OF ENVIRONMENTAL CONDITIONS ON FLOWER INITIATION AND DEVELOPMENT OF ALLIUM SPHAEROCEPHALON L. |
| Authors: | J. Berghoef, A.P. Zevenbergen |
| Abstract:
Flower initiation of Allium sphaerocephalon is not taking place during dry storage of the bulbs at temperatures ranging from 2–21°C. Storage for a minimum of 8 weeks at 2–13°C accelerates flowering after planting irrespective of growth conditions. Planting the bulbs in autumn requires a low temperature of 9–13°C and a daylength of 16–24 hours for flower initiation. Higher temperatures and/or a daylength of 8 hours keep the plants in the vegetative stage, the apex continues to initiate leaves. Elongation of the inflorescence stalk is enhanced by increasing the temperature to 17–20°C after the inflorescence has become visible outside the leaf sheath. A long day of 16 hours at that time accelerates flowering and improves inflorescence quality by increasing the size. Bulbs can be stored at 0.5°C until early July giving an acceptable percentage of flowering plants, provided that it is preceded by a storage for 12 weeks at 20–23°C. The flowering period of Allium sphaerocephalon can be extended from April till September with a high percentage of flowering plants and reasonable flower quality. For further improvement of inflorescence quality research for optimization of growth conditions is required. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
