EFFECT OF Na₂So₄ ON THE GROWTH, WATER RELATIONS, PROLINE, TOTAL SOLUBLE SUGARS AND ION CONTENT OF <i>ATRIPLEX HALIMUS</i> SUBSP. <i>SCHWEINFURTHII</i> THROUGH <i>IN VITRO</i> CULTURE

Resumen

Atriplex halimus subsp. Schweinfurthii is a perennial halophyte, which is widely distributed in the Algerian salt steppes. This study reports the effect of sodium sulphate (Na₂SO₄) on the growth, tissue water content, proline, total soluble sugars and ion content of the species under in vitro conditions. Optimal growth was observed at 50mM Na₂SO₄ and declined with a further increase in salinity. Water potential (Ψ_w) of plants became more negative with an increase in salinity. Ca²⁺, Mg²⁺, and K⁺ concentration of plants decreased with increasing salinity, while Na⁺ and SO₄^2- increased. Both proline and total soluble sugars content of shoots and roots were highest at 250 mM Na₂SO₄. This study has demonstrated that salt tolerance in A. halimus subsp. Schweinfurthii is achieved by appropriate osmotic adjustment involving accumulation of inorganic and organic solutes. At high salinities, growth reduction probably occurs as a result of high concentrations of Na< sup>+ and SO₄^2- and their interference with other ions such as K⁺. This variety can be used locally as a fodder for livestock and could be useful in sand dune stabilization.