Abstract

Changes in availability of metabolites during seed deterioration might damage processes of synthesis and energy release for embryonic growth. This research aimed to determine which alterations occur in metabolic profile over storage of Araucaria angustifolia seeds and how these alterations are related to viability loss. Metabolic profile of samples stored at 60, 120, and 180 days, at ambient temperature, refrigerator (5°C), and freezer (-18°C), was analyzed by Fourier transform mid infrared (FTIR) spectroscopy. Additionally, soluble proteins of embryos and soluble carbohydrates and starch of megagametophytes were also quantified and related to dry matter and seed germination. Presence of primary and secondary metabolism compounds was identified in embryos (starch, proteins, lipids and phenolic). Both embryos and megagametophytes are composed principally of carbohydrate and starch. At 180 days of storage, only freezer-stored samples maintained a metabolic profile similar to freshly harvested samples, but seed viability was dramatically reduced. Storage in refrigerator can be an alternative to control the catabolism of reserve compounds in A. angustifolia seeds, retaining about 70% germination.

Key words: Araucaria angustifolia, germination, Fourier transform mid infrared (FTIR), metabolic profile, seed deterioration.