Assessing the germinability of coastal Limonium minutum (Plumbaginaceae) under different temperature and salinity conditions: implications for its conservation

Abstract

Background and aims – Limonium minutum is an endemic plant of the eastern Balearic Islands (Majorca and Minorca), where it grows in coastal rocky habitats. The effects of temperature and salinity on seed germination of Limonium minutum were evaluated in order to set a protocol for recovery of this species in this habitat.Material and methods – Experiments to determine the effect of temperature have been carried out at temperature conditions between 10 and 23°C. Tests to determine the effect of salinity have been evaluated at 18°C with concentrations of 0, 100, 200, 300, and 400 mM of MgCl2, MgSO4, NaCl, and Na2SO4.Key results – Maximum germination took place between 16 and 20°C. Based on the salinity tests, the highest germination values were obtained with distilled water. The use of saline solutions resulted in significant decreases in the germination percentage. However, in almost all treatments, seed germination was observed. The T50 increased at low temperatures and with increasing salt concentration.Conclusion – Limonium minutum has a wide germination temperature range and a high resistance to salinity. After being exposed to different saline solutions, once washed with distilled water, the seeds recover their full germination capacity; therefore, the effect of salts is an osmotic and non-toxic effect for this species. Sowing seeds in late August ensures that the species has an optimal chance to survive in coastal habitats.