EMBEBIÇÃO, OSMOCONDICIONAMENTO E VIABILIDADE DE SEMENTES DE Apuleia leiocarpa (VOGEL.) J. F. MACBR.

Abstract

The aim of this work was to characterize the imbibition and to evaluate the physiological quality of Apuleia leiocarpa seeds after priming. It was done the immersion of intact and scarified seeds in distilled water for 96 hours. In the study of priming, the scarified seeds were separate on three lots (L1, L2, L3), the first has been conditioned in distilled water only (control), the second and the third were osmoconditioned in PEG 6000, at potentials of -0.4 and -0.8 MPa, respectively, for 10 hours. Then, the seeds were placed in plastic bags and kept under controlled temperature of 3°C ± 1. Sowing was performed after 0, 30, 60, 90 and 120 days of priming. Seed quality was evaluated by: germination percentage, germination speed index, relative frequency of germination, root length, shoot length, and seedling dry weight. The seed imbibition of Apuleia leiocarpa follows the three-phase model of water absorption, starting after three hours and culminates with the primary root protrusion after 72 hours. The primed seeds in -0.8 MPa of PEG maintained the physiological quality of seeds, while seeds primed in water and -0.4 MPa of PEG linearly reduced the percentage and speed of germination, the length and the dry weight of seedlings.