Métodos de superação da dormência na emergência de Cuspidaria pulchra, Cham., L.G.Lohmann, BIGNONIACEAE

Cuspidaria pulchra (Cham.) L.G.Lohmann (Bignoniaceae), popularly known as the cipó da mata, which has aroused the interest of the scientific community by the presence of ursolic acid, a pentacyclic triterpenoid compound, isolated from their leaves and stems. It has been reported that ursolic acid possesses a wide range of biological activities, such as anti-inflammatory and anti-carcinogenic activities, sedative, analgesic and trypanosomicide. Despite the above characteristics, little is known about the species, especially as regards their spread. The objective of this study was to identify an effective method to overcome dormancy in C. pulchra seeds. The experiment was conducted in CRD with four treatments: T1-control; T2-seeds soaked in distilled water for 20 minutes; T3-seeds soaked in distilled water for 40 minutes and with a winged edge removed; T4-soaking into distilled water for 40 minutes and with whole extension winged removed. At the end of 30 days seedling emergence was counted, and, the speed of emergence index (SEI) and the mean emergence time (MET) were calculated. The results show no statistical differences regarding emergency %. The T4 treatment had the lowest TME; As the IVE in T2 and T4 were higher than the control treatment. T4 provided a greater uniformity among the treatments.Cuspidaria pulchra (Cham.) L.G.Lohmann, conhecida popularmente como cipó da mata, é uma liana da família Bignoniaceae, que tem despertado interesse da comunidade científica pela presença do ácido ursólico em suas folhas e caules. Esse ácido possui atividades antiinflamatórias, hepatoprotetoras, analgésicas, cardiotônicas, sedativas, tônicas e tripanossomicidas. Apesar das características mencionadas pouco se sabe sobre a espécie, principalmente no que diz respeito a sua propagação. O objetivo deste trabalho foi estabelecer diferentes métodos de superação da dormência na emergência de C. pulchra. O experimento foi realizado em DIC com 4 tratamentos: T1 (Controle); T2 (Sementes embebidas com água destilada por 20 min.); T3 (Sementes embebidas com água destilada por 40 minutos e com uma extremidade alada removida); T4 (Sementes embebidas com água destilada por 40 minutos e com toda extensão alada removida). Ao término de 30 dias foram avaliadas a percentagem de emergência (% de Emergência); Tempo médio de emergência (TME) e índice de velocidade de emergência (IVE). Os resultados mostram que não houve diferenças estatísticas quanto à % de emergência. O tratamento T4 apresentou o menor TME; Quanto ao IVE os tratamentos T2 e T4 foram superiores ao tratamento controle. O T4 proporcionou maior uniformidade entre os tratamentos estudados

Effect of salt stress on the growth of Lippia gracilis Schauer and on the quality of its essential oil

This study evaluated the effect of salt stress on the growth of Lippia gracilis Schauer, a species native to the caatinga (shrublands) of Brazil and rich in essential oils, as well as on the quality of its oil. We exposed individuals of L. gracilis to NaCl, in the following concentrations, for a period of 40 days: 25 mM; 50 mM; 75 mM; and 100 mM. An additional group of plants was not exposed to NaCl (controls). Data were collected on days 20 and 40. We evaluated relative growth rate; shoot and root dry weight; relative water content; proline concentration in leaves; and chemical composition of the essential oil. At all concentrations, NaCl reduced the relative growth rate in comparison with that observed for the controls. No significant difference in relative water content was observed among treatments. In all treatments, the proline concentration in leaves was highest on day 40. Salt stress did not affect the yield or the concentrations of the constituents of the essential oil of L. gracilis, carvacrol and thymol showing the highest concentrations in all treatments