Physiological and morphological aspects of seed viability of a neotropical savannah tree, Eugenia dysenterica DC.

The morphology of Eugenia dysenterica DC. (Myrtaceae) seeds and post-seminal development was studied and its germination response investigated in relation to temperature, desiccation under different drying regimes and storage under three temperatures. The seeds are elliptical, varying from globose to half-globose and seedlings are cryptogeal with long and slender axial roots. High germination percentages were achieved at temperatures ranging from 15° to 30°C and the thermal optimum was about 24°C. Seeds presented high moisture contents on shedding (47-53%) and completely lost viability when moisture contents were reduced to values below 18-22%; a straight-line relationship was observed between the probit of germination and moisture content percentage. These characteristics provide evidence of a recalcitrant storage behaviour of this species. Storage at near 45% moisture content enabled seed survival for 175 days with over 50% viability, in spite the storage temperature.