Efeito do fotoperíodo na germinação de sementes de Bromelia antiacantha Bertol

Abstract

Brazil has the greatest biodiversity in the world, due to its territorial extension and the different biomes that make it possible to adapt to different species, and to know the ways of knowing things about the germination of some species, especially for the conservation of species. The objective of this work was to evaluate the effect of different light periods of the seed in Bromelia antiacantha Bertol., A native species of Rio Grande do Sul, belonging to the family Bromeliaceae, occurring in high humidity soils of restinga and in degraded environments. The experiment was conducted at the Laboratory of Plant Physiology of the Federal Universidade Federal da Fronteira Sul, in Cerro Largo - RS. The seeds were collected from mature fruits of Bromelia antiacantha Bertol., From the city of Santo Cristo, RS. The seeds were cleaned in running water, dried and stored at room temperature. It was used a completely randomized design (DIC), with 4 treatments, which were related to different light addition regimes (0/24, 8/16, 12/12, 16/8 hours), with six replicates of 25 seeds , totaling 24 experimental units. The parameters evaluated were the percentage of germinated seeds, the Germination Speed Index (IVG), and the percentage of normal and abnormal seedlings. The data were compared by analysis of variance by the agricultural statistical program SASM-Agri and submitted to regression analysis, with adjustment by spreadsheet. All the light addition periods tested have an effect on the evaluated parameters. For the percentage of germinated seeds, the period of greatest exposure to light tested (16 light-days.day -1 ), presented higher percentages. With regard to the germination speed index (IVG) and seedling development, they showed maximums with 9 light hours.day -1 and 15 light.day -1 , respectively, for these parameters, the best results were found between periods between 8 and 16 hours of light.day -1 . With this, it is concluded that in the presence of light, germination and seedling development are favored.