Qualidade fisiológica de sementes de acacia farnesiana (l.) willd. após tratamentos pré-germinativos

Abstract

The Acacia farnesiana (L.) Willd., popularly known as corona, aromita, clorana, cassie, espinilho, sponge, sweet acacia, among others is a shrub or small tree, much branched, thorny, extensive crown and foliage bi-stroke, occurring from Mexico to the Northeast of Brazil, usually associated with dry areas with strongly seasonal climate. The aim of this study was to evaluate methods for overcoming seed dormancy of A. farnesiana, as well as the effect of different temperatures in conducting germination test. To overcome seed dormancy treatments used were: immersion in water at a temperature of 60, 70, 80, 90 and 100 °C for one minute (T1, T2, T3, T4, T5, respectively), immersion in sulfuric acid (H2SO4) for 10 and 20 minutes (T6 and T7, respectively), immersion in sulfuric acid for 10 minutes, with subsequent soaking in water for 12 and 24 hours (T8 and T9 respectively), immersion in sulfuric acid for 20 minutes with subsequent soaking in water at room temperature for 12 and 24 hours (T10 and T11, respectively), scarification sandpaper n°. 80 (T12), scarification followed by soaking in water at room temperature for 12 and 24 hours (T13 and T14, respectively) and control - intact seeds (T15), and the germination test conducted at temperatures of 20-30 °C and 25 alternating and 30 °C constant. The most effective treatment to overcome dormancy of seeds of A. farnesiana in sandpaper scarification is soaking in water for 24 hours, when coupled with the constant 25 and 30 °C for installation of the germination test.