The natural flowering of pineapple, besides
being influenced by climatic factors, undergoes the
effects of the rate of development of the plant, being
necessary that the plant reaches an appropriate size
– the ontogenetic maturity, to answer to the
environmental stimuli (LACOEUILHE, 1975; BARTHOLOMEW
and KADZIMIN, 1977), as it was also observed in
ornamental Bromeliaceae by MEKERS and DE PROFT
(1983). The referred minimum size is reached in
shorter periods under favorable conditions, than
where the growth is retarded by lack of nutrients and
water and by low temperature (BARTHOLOMEW and
MALÉZIEUX, 1994). In practice, however, it has been
observed that even small plants present some capacity
to be induced under favorable floral stimuli, either
natural or artificial (CUNHA, 1989b). Plant maturity for
flowering is always correlated with the capacity of the
plant in converting the exogenous 1-
aminociclopropane-1-carboxílic acid (ACC) into
ethylene (DE GREEF et al., 1983). SANEWSKI et al. (1998)
observed that the rate of ACC (precursor of ethylene)
increased about 40% in the winter, when the low
average temperature reached 14.5 oC. Plants that had
already formed the inflorescence exhibited a much
higher ACC oxidase activity in leaves and in the stem
than plants in vegetative stage (MIN, 1995). In that
case, the ethylene production in leaves was also
higher.