Ensaios para a validação de metodologias para germinação de diásporos de espécies arbóreas do cerrado

Abstract

The validation of methods for testing germination of diaspores of forest species requires extensive review of literature and knowledge about the morphofunctional aspects of seedlings. Therefore, the objective of this study was to define methodologies for testing germination of diaspores of Cerrado forest species from pilot tests to identify the particular classification used according to the morphofunctional classification of the seedling. As national and international institutions require validation of the methodologies for inclusion in their official rules, was also to evaluate the performance of these inter-laboratory methodologies for lots of diaspores of different quality. Pilot tests with methods described in the literature were performed with diaspores of different qualities of 22 species of Cerrado. The factors tested for germination were methods for overcoming dormancy, pre-soaking time and disinfection of the diaspores with sodium hypochlorite. Invasive methods to overcome dormancy can cause abnormalities in the seedlings, especially when the relative position of the seed is not taken into consideration. Pre-soaking seeds of Ormosia arborea (Vell.) Harms, Hymenaea stigonocarpa Mart. ex Hayne and Peltogyne confertiflora Benth. in water accelerates the development of seedlings and minimizes the incidence of fungi, but increases the number of dead seeds of Enterolobium contortisiliquum (Vell.) Morong. Sodium hypochlorite was effective in disinfestation of dormancy seeds of Copaifera langsdorffii Desf., Hymenaea stigonocarpa, Ormosia arborea, Plathymenia reticulata Benth. and Stryphnodendron polyphyllum Schott, besides being effective in non-dormant seeds, as Cariniana estrellensis (Raddi) Kuntze, Ceiba speciosa (A. St.-Hil.) Ravenna and Pseudobombax tomentosum (Mart. & Zucc.) A. Robyns. Seedlings of forest species have characteristics that are reported as abnormal for cultivated species. The morphofunctional classification of the seedlings assists in defining the indispensable and essential structures during the seedling evaluation moment according to technological criteria and, consequently, in the validation process.