Resumo

MACIEL, N  e  BRICENO, A. Effect of fruit ripening, seed scarification and temperature on seedling emergence of Syagrus stenopetala Burret. Rev. Fac. Agron. [online]. 2009, vol.26, n.2, pp.196-211. ISSN 0378-7818.

Syagrus stenopetala Burret is an endemic palm of the Venezuelan flora that displays morphologic attributes of appreciable ornamental value. Considering its horticultural potential and that palms are characterized themselves by a variable germination with the species, the effect of factors related to the fruit and seed on the seedlings emergence were studied. Seeds were sowed into a coconut and sand sawdust (1:1 v:v) mixing, under greenhouse conditions (80% shadow), temperature of 26 ± 5ºC and 70% of relative moisture. It was evaluated under a factorial arrangement of 2x3 (with 4 replications of 50 seeds each), the seeds use effects from fruits at different maturity degrees (fruits at the beginning of maturity and complete maturity) and its scarification (with pericarp, without pericarp and without pericarp+sulphuric acid). The higher values for the emergence final percentage (% E) in seeds of mature fruits with and without pericarp (87 and 91.5%) were obtained. The sulphuric acid use in both maturity stages, affected the E percentage in a negative way. In a second test, the seeds without pericarp were put under three temperature treatments: 26ºC (average), 30ºC constant and 30/20ºC. The variance analysis did not detected significant differences between the evaluated treatments, probably to use of immature seeds. Nevertheless, greater emergence percentage (38%) was observed in seeds under constant temperature of 30ºC. It is conclude that the S. stenopetala emergence was affected by the fruit maturity degree.

Palavras-chave : germination; palm; seedling; propagation by seed.