Floral biology of a population of <em>Mirabilis jalapa</em> L. (Nyctaginaceae) from Southern Brazil

Abstract

The reproductive pattern of a cultivated population of Mirabilis jalapa in the Southern region of Brazil was investigated. Flowers of M. jalapa opened for one night, in the early evening at 17h00 and closed early the next morning from 4h30 to 6h00. Anther dehiscence occurred from about 19h30 to 20h30. The presence of pollen grains on the stigma surface was recorded in flowers in which the anther lay at the same level as the stigma or higher. Absence of pollen grains was observed in flowers in which the anther was below the stigma and in previously emasculated flowers. One moth was reported to be the only visitor and possible pollinator of M. jalapa flowers throughout the experimental period. Self-pollination was the predominant mode of reproduction in the M. jalapa population cultured in the garden of the State University of Maringá