Phenology and reproductive aspects of <I>Paepalanthus Polyanthus</I> (Bong.) Kunth (Eriocaulaceae) in a sand dune slack, Joaquina Beach, Ilha de Santa Catarina, SC, Brazil

Abstract

All reproductive individuals of Paepalanthus polyanthus present in 300 m2 (n=120) in 1989 and in 450 m2 (n=123) in 1990 were accompanied in a sand dune slack in Joaquina Beach. The average number of umbels produced per plant was 10,09 (±3,98) in 1989 and 8,03 (±3,42) in 1990. The average diameter of foliar rosette of reproductive plants was 22,98 cm (± 4,66) and 21,15 cm ((3,76) in these respective years. A minimum size to initiate flowering and a positive correlation between size and number of umbels produced per plant were detected. In both years, the highest frequency of individuals in flower occured in November and the frutification peak in December. A great synchronism in flowering was observed between the umbels of an individual. The most frequent sequence of flower maturation was: male flowers first, femate second, and again male. The sex expression was variable. Most plants were hermafrodites, some matured only male flowers and others only femate flowers. The length of reproductive period per plant was 91 days in average, considering the time from bud formation to the begining of capitula dispersion. The plants died after reproduction.