Dormência e germinação de sementes de Uvaia (Eugenia pyriformis Cambess)

Abstract

South Brazil has a great diversity of alimentary fruit species. The uvaia (Eugenia pyriformis Cambess), along with other nativespecies, has great economic potential due to its fruits and as a feedstock for the food industry. However, there is little information on seed dormancy for this species and neither a defined official protocol regarding dormancy overcoming, a necessary requisite for large-scale production. This work aimed to verify the presence of dormancy in E. pyriformis seeds, also proposing a possible method to overcome it. The applied seed breaking treatments were: mechanical scarification with sandpaper, chemical scarification using concentrated sulfuric acid, thermal shock using hot water, chemically induced germination using gibberellic acid, a combination of sulfuric acid and gibberellic acid treatments, a combination of hot water and gibberellic acid treatments, and a control (seed without treatment). The seeds were kept incubated in a BOD incubator for 60 days at 25±5 °C and a photoperiod of 8:16 h (light:dark). The percentage of germination and germination speed index (GSI) were evaluated. The results indicated that mechanical scarification induced faster germination (GSI values of 0.637 for mechanical scarification and 0.187 for the control) and germination percentages of 77%, while the control treatment presented 36%. The fresh collected E. pyriformis seeds may present dormancy, which was overcome by mechanical scarification.