Programmed flower induction of Calathea crocata Morr. et Joris is possible under the controlled environmental conditions of a multilayer growing room. A photoperiod of 10 hours for 9 weeks, growth at 18C, and a photosynthetic photon flux density (PPFD) of 71 mumol.s-1.m-2 induced flowering in more than 95 % of the plants and in 50 % to 80% of the shoots. In the meantime, none of the plants under natural conditions was induced. Significantly more flowers were induced when PPFD during the short-day treatment was 71 rather than 56 mumol.s-1.m-2. Flowers became visible 14 to 16 weeks after the start of the inductive treatment. Moreover, raising the CO2 concentration to 900 ppm for 5 months increased the leaf area and dry weight by 40 and resulted in darker leaf color, longer flower stalks, and significantly accelerated flowering (10 days).
|Status||Gepubliceerd - 1993|