THE ROLE OF EXTERNAL FACTORS IN GROWTH AND DEVELOPMENT OF FLOWER BULBS AND BULB-FLOWERS: AN UPDATE SINCE 1992

To review the role of external factors in growth and development seems a challenging but impossible task as it concerns every phase in the life-cycle of flower bulbs and bulb-flowers.
I decided not to try covering everything but to: a) refer only to new ‘high lights’ in the production chain ‘starting material – flower quality’, for which criteria are arbitrary and consequently personal; b) discuss only processes in which hormones are involved; c) focus, if possible, on sink – source processes; d) take 1992 as the starting point.

There were two good reasons for taking 1992 as a landmark: 1. De Hertogh and Le Nard were finishing their excellent handbook in which all relevant data are very well reviewed, (De Hertogh and Le Nard, 1993); 2. The 6th International Symposium on Flower Bulbs was organized in Skierniewice, Poland, revealing new data.

In the next paragraphs I will mention the state of the art in 1992 of each phase of the production chain starting material – flower quality, together with questions raised at Skierniewice.
Almost all references in the text refer to contributions to the 6th International Symposium as published in Acta Horticulturae vol. 235, 1992, (first author and page numbers will be indicated). Then I will discuss whether answers to these questions were generated during the 7th Symposium held at Herzliya, Israel in 1996.

VII International Symposium on Flowerbulbs

P.M. Boonekamp

https://doi.org/10.17660/ActaHortic.1997.430.3