Tratamentos pré-germinativos na superação de dormência de sementes de Colubrina glandulosa Perk. (Rhamnaceae)

Abstract

Little is known about the use of plant extracts to break dormancy of forest seeds, so it is interesting to study the effect of aqueous extract of Cyperus rotundus as a treatment for overcoming seed dormancy. The aim of this study was to evaluate the efficiency of pre-germinative treatments in overcoming seed dormancy of Colubrina glandulosa Perk. The experiment was developed at the Forest Seed Laboratory of the Federal Rural University of Pernambuco. At the time, seeds of the species obtained from matrices located at the Carpina Sugar Cane Experimental Station were submitted to germination tests by applying 6 treatments with 4 replications. Each unit was characterized by 25 seeds packed in a polyethylene box containing a sheet of paper towels. The treatments were: (T1) without acid scarification + autoclaved distilled water; (T2) without acid scarification + aqueous extract of C. rotundus 5%; (T3) without acid scarification + aqueous extract of C. rotundus 10%; (T4) with acid scarification + aqueous extract of C. rotundus 5%; (T5) with acid scarification + 10% aqueous extract of C. rotundus; and (T6) with acid scarification + autoclaved distilled water. To evaluate the effects of aqueous extract of Cyperus rotundus on seed germination of C. glandulosa, we analyzed: IVG, VG and G%. The statistical design used was completely randomized and in a 2x3 factorial arrangement, considering 2 pre-germinative conditions and 3 types of wetting. Data were submitted to analysis of variance (ANOVA) and means compared by Tukey test at 5% probability. The G% and IVG results obtained showed that there was no significant interaction between the evaluated treatments and that there was a significant difference in the VG between the treatments in which the seeds were not scarified and those that received acid scarification submitted to moistening with same extract type of 10% concentrated thyroid. It was concluded that the interactions between conditioned pre-germination treatments for overcoming dormancy of C. glandulosa dispersion units were not significant.