42 L.L.C. DIAS, C. SANTA-CATARINA, V. SILVEIRA, F.P. PIERUZZI AND E.L.S. FLOH F O R M A T T E D P R O O F Dias, L.L.C., Santa-Catarina, C., Silveira, V., Pieruzzi, F.P. and Floh, E.L.S. (2009), Seed Sci. & Technol., 37, 42-51 Polyamines, amino acids, IAA and ABA contents during Ocotea catharinensis seed germination L.L.C. DIAS 1 , C. SANTA-CATARINA 2 *, V. SILVEIRA 3 , F.P. PIERUZZI 1 AND E.L.S. FLOH 1 1 Plant Cell Biology Laboratory, Department of Botany, IB-University of São Paulo (USP), Rua do Matão, 277, São Paulo-SP, CP 11461, CEP: 05422-970, Brazil (E-mail: enyfloh@usp.br) 2 Cellular and Tissue Research Laboratory – LBCT/CBB, North Fluminense State University (UENF), Avenida Alberto Lamego, 2000, Parque Califórnia, Campos do Goytacazes-RJ, CEP: 28013-602, Brazil (E-mail: claudete@uenf.br) 3 Biotechnology Laboratory - LBT/CBB, North Fluminense State University (UENF), Avenida Alberto Lamego, 2000, Parque Califórnia, Campos do Goytacazes-RJ, CEP: 28013-602, Brazil (E-mail: vanildo@uenf.br) (Accepted August 2008) Summary The aim of this work was to study biochemical variations of IAA (indole-3-acetic acid), ABA (abscisic acid), PAs (polyamines) and amino acids at endogenous levels, during seed germination in Ocotea catharinensis. Seeds were germinated in a vermiculite substratum (100%), samples being collected after 15, 30 and 60 days. Total amino acid levels decreased during the first 15 days, followed by an increment at the end of germination. Among amino acids, higher concentration was observed in asparagine, this being the predominant amino acid during the whole germination period. Total PAs (free + conjugated) content increased during the first 15 days, followed by a decrease and stabilization between 30 and 60 days of germination. Among the PAs, free putrescine levels rose during the first 15 days, followed by a drop and stabilization up to 60 days of germination, while spermidine and spermine (spm) contents diminished during the period. Only spm was detected in a conjugated form, with increasing concentrations starting from 30 days on. IAA levels increased during the first 15 days, followed by a decrease and stabilization until the end of germination (60 days), while ABA contents dwindled during the first 15 days, with similar values until the end of germination. Introduction Ocotea catharinensis Mez. is an endangered native forest tree species of the Brazilian Atlantic Rain Forest. Increasing pressure in the extraction of this species from the forest has drastically decreased its frequency in many areas, this having affected the tree’s natural reproduction mechanisms. The species produces flowers and seeds sporadically, seeds being of short viability, thus making natural propagation difficult. Remarkably little information is available on its reproductive biology, physiology and propagation (Viana and Mantell, 1999). Seeds of O. catharinensis are recalcitrant and desiccation-sensitive (Santa-Catarina et al., 2006), intolerant to higher dehydration during the maturation phase, * Author for correspondence