Effect of salinity stress on chlorophyll, carotenoid content, and proline in Salicornia prostrata Pall. and Suaeda prostrata Pall. subsp prostrata (Amaranthaceae)

Salicornia prostrata Pall. and Suaeda prostrata Pall. subsp. prostrata occur together on saline soils in Kizilirmak Delta in Samsun, Turkey. The effects of salinity stress on photosynthetic pigments and proline were investigated in these two species in natural habitats. With the increasing soil salinity, a decrease in chlorophyll (Chl) and carotenoid contents was observed in both taxa. However, in Salicornia prostrata, photosynthetic pigments levels were lower than those in Suaeda prostrata. Proline contents significantly increase with increase in salinity level in both species, whereas Salicornia prostrata produced less proline than Suaeda prostrata. Proline and Chl a contents were significantly different betweesn examined species according to soil salinity. Based on obtained data, we can conclude that at in situ conditions, Salicornia prostrata is more salt tolerant compared with Suaeda prostrata.