THE INFLUENCE OF TEMPERATURE ON PHENOLOGICAL DATING OF ORNITHOGALUM THYRSOIDES JACQ. AS A COMMERCIAL CUT FLOWER

P.J. Jansen van Vuuren, L.C. Holtzhausen
O. thyrsoides has a qualitative temperature requirement. Initiation of the inflorescence can be retarded or advanced by temperature manipulation. According to the results of this study there is a negative correlation between storage temperature and developmental rate, resulting in flowering date retardation as storage temperature increases.

Storage of the flower bulbs at 5°C for 14 weeks resulted in the earliest flowering date. With every 5°C increase in storage temperature to a maximum of 30°C the flowering date was progressively retarded a number of days. There are no meaningful statistical differences between the results of the 30°C - and 35°C treatments.

Flower bulbs of O.thyrsoides can be kept in storage for prolonged periods (6 months) at 35°C, without detrimental effects on the flowering characteristics.

The flowering date is the most important part of phenological dating. This date can now be manipulated, without any detrimental effects on the flowering characteristics. Data from the experiments on the influence of temperature on the flowering date were used to compile a phenological model. This extrapolated model were compiled to determine the storage periods and planting date for the production of cut flowers according to a predetermined flowering date. The model is now being tested for validity.

Jansen van Vuuren, P.J. and Holtzhausen, L.C. (1992). THE INFLUENCE OF TEMPERATURE ON PHENOLOGICAL DATING OF ORNITHOGALUM THYRSOIDES JACQ. AS A COMMERCIAL CUT FLOWER. Acta Hortic. 325, 119-130
DOI: 10.17660/ActaHortic.1992.325.13
https://doi.org/10.17660/ActaHortic.1992.325.13

Acta Horticulturae