Effect of aluminum on the growth of the in vitro culture tissues of the date palm (Phoenix dactylifera L.) cv. Um-Aldehin

This study was carried out to evaluate the effect of different concentrations of aluminum: (25, 50 and 100 mg l⁻¹ of aluminum chloride AlCl₃. 6H₂O) on the enhancement of shoot multiplication, phytochemicals, as well as, antioxidant enzyme activity of in vitro cultures of the date palm cv. Um-Aldehin. The addition of aluminum in a concentration of 50 mg l⁻¹ to the medium exhibited most effects on shoots regeneration and this substance also increased the number of shoots per a jar (73.34% and 8.2 shoots/jar, respectively), compared to the other concentrations, including the control treatment. A biochemical analysis of date palm shoots revealed that the high concentration of aluminum chloride (100 mg l⁻¹) led to a significant accumulation of the total proline content, and to a high activity of ascorbate peroxidase, as well as a significant reduction in nitrogen, phosphorus, calcium, magnesium and chlorophyll, compared to the concentration of 50 mg l⁻¹ for which there were recorded the highest contents of the mentioned elements, together with the highest content of chlorophyll in leaves.