Evaluation of Germination under Different Storage Conditions of Four Endemic Plant Species from Ethiopia: Implications for Ex Situ Conservation in Seed Banks

The conservation of endemic plant species is a major concern, as the species are with restricted distribution range. Since in situ conservation alone will not guarantee their maintenance, ex situ conservation measures must be undertaken to support the conservation of these species. Investigation of the impact of the storage environment of seeds gives baseline information. Therefore, this study was conducted to investigate the effect of different storage conditions (room temperature, 4 °C and −10 °C) and different storage periods over one year. Four Ethiopian endemic plant species, namely Euryops pinifolius, Kniphofia foliosa, Lobelia rhynchopetalum, and Solanecio gigas, were considered. Multivariate analyses revealed a significant (p < 0.05) effect of storage condition and period on seed germination. The storage of seeds at room temperature before drying may not be recommended for short-term storage of the studied species, except K. foliosa. After drying of seeds, E. pinifolius, K. foliosa, and L. rhynchopetalum seeds showed high germination percentage (above 80%) after storage even at sub-zero temperatures for one year. The germination percentage of S. gigas stored at room temperature before drying for thirteen months was 60% and that stored at 4 °C was 6%, which indicates that the seeds may be categorized under intermediate storage behavior. The three species can be grouped in the orthodox seed storage category. Research on desiccation screening should be undertaken to predict an optimal combination of storage moisture content and suitable storage temperature to determine storage category with certainty.