CONTROL OF FLOWERING IN BROMELIADS
In the fourties, Clark & Kerns (1942), Cooper (1942) and van Overbeek (1945, 1946) published their results with napthalene-acetic acid (NAA), and dichlorophenoxyacetic acid (2,4-D) in flower induction in pineapples and in 1955 Gowing & Leeper found flower initiation after treatment with beta-hydroxyethylhydrazine (BOH). In the following years, these two authors found about 100 active compounds which induce flowering in pineapple.
Before 1960 only a few publications about flower induction in other bromeliads than pineapple are available. In the specification of his patent, Kerns (1936) mentioned acetylene-treatment at Billbergia, and Foster (1943) reported successful treatments of some Aechmea's with acetylene and ethylene.
A few years ago - in 1960 and 1962 - research on this problem started in The Netherlands and in Germany. Results of these investigations lead to an increase in production of bromeliads as is shown in table 1.