Effect of Phosphorus and Magnesium Treatment on Root Structure of Salicornia spp.

Due to the severe limitations of fresh water in Iran, the use of low-quality saline water resources is an inevitable necessity in development of sustainable agriculture. One of the ways to deal with climate change is to use the potential of halophyte plants such as Salicornia for the economic utilization of saline soils. In this study, two genotypes of Salicornia (Qom, sensitive to salinity and Helleh, tolerant to salinity) were hydroponically treated with salinity and different concentrations of phosphorus (P) and magnesium (Mg). The aim of this study was to investigate the role of these two elements on growth factors and morphological and anatomical characteristics in Salicornia under the salinity treatments. The results showed that at 0 mM salinity, P could stimulate growth in both genotypes. But at 200- and 800- Mm salinity, had a negative effect on growth parameters. Increasing the concentration of Mg at all three salinity levels(0, 200, 800mmol) improved growth in both genotypes. Also, the lack of P in 200-and 800-mM salinities affected the plant anatomy and caused lignification areas in the endoderm and increased diameter in the cell wall of the xylem. In addition, a 3-fold concentration of Mg at 800 mM salinity severely deformed and plasmolyzed epidermal and parenchymal cells. Overall, these studies showed that a one-fold treatment of Mg and P provides the best conditions for the growth of Salicornia.