Determination the threshold of salinity tolerance in Salicornia species using Persian Gulf water

Intensification salinization of water and soil resources requires more attentions to halophytes species cultivation. In this research, the effect of salt stress as varied percentage (control, 15%, 30%, 45%, 60%, 75%, 90% and 100%.) of Persian Gulf water (58 dS m-1) was examined on germination and seedling growth of different Salicornia species, in order to determine salinity tolerance threshold and threshold of 50% reduction in germination at National Salinity Research Center, Yazd in 2017. Species consisted of Salicornia europaea, S. bigelovii along with three local populations: Khor-e-Mozain (Bushehr province), Ilkhchi (East Azerbaijan province) and Markazi (Iran central regions). The results showed that the mean germination of the species were significantly reduced from 25% Persian Gulf water, however germination of all species did not stopped even at 100% Persian Gulf water. However, seedling length in Khor-e-Mozain, S. europaea and S. bigelovii was decreased as salinity was intensified, while in Ilkhchi and Markazi were increased up to 45% and 60% Persian Gulf water, respectively and then was reduced. In general, all Salicornia species had high salinity tolerance, however there were considerable variations between different species, so that salinity tolerance threshold of Khor-e-Mozain, Ilkhchi, Markazi, S. europaea and S. bigelovii were 14.36, 5.01, 14.46, 11.91 and 7.54 dS m-1 and their threshold of 50% reduction were 56.25, 51.60, 61.15, 32.69 and 27.01 dS m-1, respectively.