GERMINATION AND SEEDLING GROWTH OF <em>ACACIA</em> <em>RADDIANA</em> AND <em>ACACIA</em> <em>NILOTICA</em> AT DIFFERENT LEVELS OF SALINITY AND DROUGHT UNDER <em>IN</em> <em>VITRO</em> CONDITIONS

Abstract

An in vitro experiment was conducted to study seed germination and growth of Acacia raddiana and A. nilotica seedlings under induced water deficit and salinity conditions. Different concentrations of either sodium chloride or mannitol (0.1, 0.2, 0.3 and 0.4 M) were used to induce salt and drought stresses. In vitro seed germination of A. raddiana and A. nilotica decreased as the salinity and drought stress increased. Acacia raddiana and A. nilotica survived in vitro a concentration of 0.4 M NaCl; thus the two species could be classified as moderately salt tolerant. They also survived in vitro a high concentration of mannitol. Therefore, the two species can be classified as drought-enduring plants. Acacia raddiana was more tolerant to drought stress than A. nilotica.