Imbibition and germination of seeds of three Acacia species from Ethiopia

Abstract

Imbibition and germination of seeds of three Acacia species from Ethiopia, namely Acacia nubica, A. seyal and A. horrida, were tested in laboratory conditions. Heat treatments had a positive effect on imbibition rates for all three species. The best treatment was 60°C for two hours, a longer time of exposure having a negative effect on the seeds. A positive response to light was detected in A. nubica and A. seyal, while seeds of A. horrida responded with indifference to light. A high degree of hard-seededness— over 90%—was common in all three species. Although temperature had a positive effect on germination rates, only scarification of seeds proved to be effective in overcoming hard-seededness.