FACTORS INFLUENCING THE RESPONSE TO PHOTOPERIOD (LD TREATMENT) DURING THE WINTER IN AN AUTUMN-PLANTED CARNATION CROP

L.D. Sparnaaij, J.F. Demmink, H.J.J. Koehorst-van Putten
In an autumn-planted crop, varietal differences in response to LD treatments are analysed. Long days (24 hours per day) are given for 2 or 3 weeks in December and/or January. Average flowering date of the first flush is used as the main parameter. LD does not induce flowering in all shoots. LD effect may be better expressed as percentage shoots induced to early flowering.

Reaction of individual shoots appears to depend on:

  • position of the shoot on the main stem
  • number of leaf pairs of the shoot at the start of the LD treatment
  • speed of development of the shoot (in terms of leaf pairs unfolded per unit of time)
Sparnaaij, L.D., Demmink, J.F. and Koehorst-van Putten, H.J.J. (1987). FACTORS INFLUENCING THE RESPONSE TO PHOTOPERIOD (LD TREATMENT) DURING THE WINTER IN AN AUTUMN-PLANTED CARNATION CROP. Acta Hortic. 216, 303-312
DOI: 10.17660/ActaHortic.1987.216.40
https://doi.org/10.17660/ActaHortic.1987.216.40

Acta Horticulturae