Current knowledge about Na2SO4 effects on plants: what is different in comparison to NaCl?

In some areas of the world, high levels of sodium sulfate (Na2SO4) are found in the soil together with sodium chloride (NaCl). However, most studies on salinity are performed utilizing only NaCl as a salinizing agent. Generally, plant species have different tolerance/susceptibility responses when grown in the presence of these salts. Some studies showed that Na2SO4 seems to be more inhibitory than NaCl for the growth of species such as barley, wheat, sugar cane, beet, tomato, wild potato, and others. However, studies focusing on how Na2SO4 can affect the biochemical and physiological processes of plants are very scarce. This review provides an overview on the effects of Na2SO4 on different crops and plants species with a special emphasis on the tolerance/non-tolerance mechanisms of the halophyte Prosopis strombulifera under elevated NaCl and Na2SO4. A better understanding of the tolerance mechanisms in this particular species will help to identify cultivars of crop species that are more tolerant to Na2SO4. This knowledge could be used to extent cultivation of certain crop plants on Na2SO4 containing soils.