Efficiency of different methods in breaking the dormancy of Erythrina lysistemon Hutch. seeds

Abstract

Erythrina lysistemon seeds imported to Libya go through a stage of being unable to germinate; we call this phase "dormancy". The present study evaluated the efficiency of the following methods in breaking the dormancy of newly collected Erythrina lysistemon seeds from mature pods and stored for 12 months: untreated seeds (control), mechanical scarification with sandpaper, soaking treatments (tap water for 24 h, hydrochloric acid for 60 min, hydrogen peroxide for 48 h, acetone for 72 h, Clorox cleaner for 72 h, cow dung and chicken manure for 24 h, and hot water at 100° C for 30 min), scarification with soaking (distilled water for 24 h, and cow dung and chicken manure for 12 h). All treatments showed a significant increase (p<0.05) in the germination rates of newly collected E. lysistemon seeds from mature pods, except for the treatment in which seeds were soaked in tap water for 48 h, which was ineffective. The different scarification treatments were more efficient than the other treatments, recording the highest germination percentages and lowest mean germination times, while the soaking treatments led to high seed mortality. In contrast, seeds stored for 12 months showed a significant decrease in germination percentage with a delayed mean germination time compared to newly collected seeds under all tested treatments. Soaking all treatments was ineffective in breaking the dormancy of E. lysatetemon seeds stored for 12 months. The results indicate that E. lysistemon seeds have physical dormancy that can be overcome using different scarification.