Understanding the behavior of the Euterpe precatoria (Mart.) palm seeds subjected to conventional ex situ conservation methods

Abstract

The sustainable use of palm trees requires studies on various aspects of seed physiology, as seeds often serve as the primary means of natural propagation. This study aimed to evaluate the effects of desiccation and storage at different temperatures on the physiological quality of seeds and zygotic embryos of Euterpe precatoria. Seeds were artificially desiccated for seven periods (0, 24, 48, 96, 120, 168 and 216 h) and, after each period, were subjected to germination tests using both whole seeds and zygotic embryos. For conservation, pre-desiccated seeds and embryos with different water contents were stored under different conditions: − 196 ºC (liquid nitrogen), - 20 °C, 6 ºC, and 25 ºC for 30 days. Additionally, morphoanatomical and histochemical analyses of zygotic embryos from dried seeds were performed. E. precatoria seeds exhibited high sensitivity to desiccation, with critical germination and vigor thresholds observed at a water content of 16.9%. Water contents of 12.0 and 8.9% had lethal effects on germination, regardless of the germination method. The presence of phenolic compounds and vacuolated cells, identified through anatomical analysis, confirmed the species’ recalcitrant behavior and revealed physical damage in zygotic embryos with water contents below 8.9%. These findings indicate that E. precatoria seeds are desiccation-sensitive, and none of the tested storage temperatures effectively preserved their physiological quality.

Key message

Euterpe precatoria seeds are highly sensitive to desiccation, with critical germination and vigor thresholds observed at a water content of 16.9%.