P.M. Boonekamp, J.C.M. Beijersbergen, J.M. Franssen
In order to identify parameters that are indicative for a successful cold treatment of tulip bulbs, a joint project of the Bulb Research Centre, four Dutch universities and ATO (Institute of Agrotechnological Research) has been started. The initial aim is to collect fundamental knowledge on physiological changes in tulip bulbs during the special precooling as described by De Hertogh (1985). Parameters that are being studied include:
  • the plant growth regulators gibberellins (HPLC coupled to GC-MS detection), abscisic acid, and indole-3-acetic acid (ELISA); in addition changes in sensitivity of particular bulb organs to these growth regulators will be studied;
  • mineral contents, metabolism and mineral transport from the bulb scales to the sprout;
  • storage and newly synthesized proteins (SDS-PAGE and 2D gel electrophoresis) and isoenzyme activities;
  • membrane characteristics of the microsomal fractions and of mitochondria (fluidity, (phospho) lipid content, enzyme activities);
  • respiratory characteristics of isolated mitochondria and ethylene production of whole tulip bulbs.

The latter parameters will be presented in more detail during this symposium (W. Kanneworff).

If cold-dependent parameters are found that are strongly related both to a proper cold treatment and to subsequent flowering, a practical assay will be developed. The aim of this assay is to predict whether a particular bulb has received the right cold treatment to have the capacity to produce an optimal flower later on. If this succeeds quality control of bulbs with respect to flower production will be possible.

Boonekamp, P.M., Beijersbergen, J.C.M. and Franssen, J.M. (1990). THE DEVELOPMENT OF FLOWERING ASSAYS FOR COLD-TREATED TULIP BULBS. Acta Hortic. 266, 177-182
DOI: 10.17660/ActaHortic.1990.266.22

Acta Horticulturae