Is the pollination efficiency of the long-lived flowers of orchids affected by age?
Palavras-chave:
floral biology, fructification, Orchidaceae, stigma receptivityResumo
The long-lived flowers of orchids increase the chances of pollination and thus the reproductive success of thespecies. However, a question arises: does the efficiency of pollination, expressed by fruit set, vary with the flower
age? The objective of this study was to verify whether the flower age of Corymborkis flava (Sw.) Kuntze affects
pollination efficiency. The following hypotheses were tested: 1) the fruit set of older flowers is lower than that of
younger ones; 2) morphological observations (perianth and stigmatic area), stigma receptivity test by using a solution
of hydrogen peroxide and hand-pollination tests are equally effective in defining the period of stigmatic receptivity.
Flowers were found to be receptive from the first to the fourth day of anthesis. Fruit set of older flowers (third and
fourth day) was lower than that of younger flowers. Morphological observations, the stigma receptivity test and
hand-pollinations were equally effective in defining the period of stigmatic receptivity. However, to evaluate the
maximum degree of stigma receptivity of orchid species with long-lived flowers, we recommend hand-pollinations,
beyond the period of receptivity.
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