Interactive Effects of Cd and NaCl on Growth and Mineral Nutrition in Hordeum vulgare L. (Var. Raihane)

In this work, we investigated the combined effect of salt and cadmium on plant nutrition and Cd accumulation in the most cultivated barley variety in Tunisia, Raihane. Seedling were hydroponically subjected to four different treatment: the control without salt and Cd, 50mM NaCl alone, 10µM Cd alone and to the combination of Cd (10 µM) and NaCl (50 mM) during 1 month. At the harvest, plant growth, Cd content in shoots and roots and tissue nutrient concentrations in shoots(Ca, Fe, Mn and Zn) were measured. 50 mM NaCl alone does not significantly affected the morphology and the biomass of plants. However, when subjected to 10 µM Cd alone, plants of barley were less developed and produced low biomass as compared to control ones. NaCl addition to the Cd-treated plants further reduces the development and biomass production. With respect to nutrient acquisition results showed that NCl alone reduced Ca2+ and Fe2+ concentration in the shoots but not affected that of Zn and Mn. But Cd, applied alone or combined with NaCl disturbed all measured element concentration in the shoots. However, the addition of salt to the Cd-containing medium reduced significantly Cd accumulation in the roots and the shoots of plants. In conclusion, salt in the water irrigation is able to reduce Cd accumulation in this barley variety but it accentuated in the same time the toxic effect of this heavy metal in barley.