Germina??o de sementes e emergência de plantulas de Tabebuia rosea (Bertoloni) a.p. de Candolle (Bignoniaceae), uma espécie exótica com potencial invasor

摘要

The objective of the present work was to analyze temperature and light effects on seed germination of Tabebuia rosea, as well as to evaluate the influence of sun and shade environments on seedlings emergence and recruitment. Constant temperatures from 10 to 45oC, with 5oC intervals, under white light and dark regimes were tested. The optimum temperature range for seed germination was between 20 and 40oC under white light and 20 to 35oC under dark. High synchronization index of seed germination was obtained at 25oC under white light and 30oC in dark. Our results indicate that seeds of Tabebuia rosea can germinate in a wide range of temperature in open environments and in places where light do not reach, buried in the soil or beneath the forest canopy. The seed germination and recruitment percentage under both direct sun light and canopy indicate the invasion potential of the species.