Harvest times of Comanthera elegans, a worldwide traded Brazilian species of everlasting flower: implications on seed production, germination, and on species management

Abstract

Comanthera elegans (Bong.) L.R. Parra & Giul (“sempre-viva-pé-de-ouro”) is one of the most economically important species among the Eriocaulaceae in Brazil. Its inflorescences are used to make handicrafts and have long been exported to all over the world. The collection period usually begins in the second half of April and extends to May, occasionally until the first half of June. We assessed seed production and germinability throughout the 2006 harvest season: April–November, as well as the variation in morphology and anatomy of inflorescences along this period. In the evaluated flowering, seeds still had not yet been completely formed by early April, the onset month of commercial collection. Instead, germinable seeds were first observed in May, while seed dispersal was already in progress in early June. Collection in June resulted in plant uprooting, due to the tighter attachment of the scape to the rosette. The beginning and peak of germination occurred earlier for seeds from the most delayed collections, and the highest germinability was presented by seeds collected in September. We showed that the best period for the plant sexual reproduction surpasses the best period for commercial collection. Due to the onset of germinable seeds only as late as at the second half of the harvesting period, encouraging the delayed beginning of inflorescence collection may well represent a management strategy. Furthermore, the reservation of non-harvesting areas, which would secure the maintenance of plant populations in the wild and thus guarantee seed production and dispersal; maintaining remnants of inflorescences in collected areas; and encouraging cultivation should be considered.