Morfologia e germinação de sementes de Alcantarea Lahoumii (Leme) J. R. Grant (Bromeliaceae)

Abstract

Alcantarea nahoumii is a bromelic rupicol, endemic of rock environments in the Serra da Jibóia, Bahia, Brazil, with high ornamental potential, therefore little known by scientists. It has been explorer in an extractive way. The objective was to descript the morphology of fruits, seeds and the post seminal development, test the substrates and temperatures of germination and vigor of seedlings, looking for amplifying the comprehension of the reproductive strategies and possible their conservation. The morphology of the fruits, seeds and seedlings were descript and illustrated. The germination was tested at 25 ºC in BOD with 4 replications of 100 seeds in sand, paper, Plantmax® and ermiculite, where they were physical characterized. The germination was tested on the paper in darkness. The effect of the temperature was evaluated in seeds germinated at 20, 25, 30 and 35 °C. The strength of the seedlings was evaluated at the end of the experiments using the size of aerial length part and the roots and the total fresh matter. The first and last count was determinate. The fruits are septicide capsules with spontaneous dehiscence. The seeds are filiform, small and light, with the presence of a proximal and distal papus. The germination is criptoepigeial, initiated in the tenth day. The seedlings present slow development. The germination occurs, preferentially, in the presence of light and the substrates has little effect over it, affecting the strength of the seedlings. The highest growth of the seedlings was using Plantmax®, after 60 days. The germination at 35°C limited the germination process and growth of the plants. The morphology of the seeds allows it dispersion by the wind, although the slow development of the seedlings could reduce the recruitment in their natural environment. Substrates with density, total porosity and water retention capacity, could be used in germination tests with temperatures of 25°C. The first count could be done after 18 days and the final count at 54 days.