IONIC CONTENT AND ABSCISIC ACID RELATIONS OF ANASTATICA HIËROCHUNTICA L. UNDER ARID CONDITIONS

Abstract

Anastatica hierochuntica L. plants are exposed in their natural environment in the Negev Desert to high sodium, calcium, and chloride concentrations and to phosphate and nitrate deficiency. Their proline content is very high, especially in fruit. Abscisic acid (ABA) concentrations in tissues respond to stress weakly and inconsistently. In the xylem sap, however, ABA concentration increases drastically when a threshold of stress (ψ ≈ 0.8 MPa) is reached. ABA induces stomatal closure and inhibition of internode growth in Anastatica plants.