Foliar behavior of olive trees (Olea europaea L.) grafted and cut under the effect of salt stress

Olive (Olea europaea L.) is an important perennial crop in many agricultural regions of the Mediterranean countries but it is planted, often in salty soils. In this context, the objective of this work is to determine the effect of salinity on the morphophysiological behavior of young olive plants in cuttings and grafted plants, including two local varieties (Chemlal and Sigoise) and two introduced varieties (Manzanilla and Arbiquina). The experiment was conducted in a laboratory and greenhouse with a well-controlled condition. The experiment was arranged in a completely randomized design of two factors (salinity and varieties) with four replications and two treatments. Not treated plants (without NaCl application) were utilized as control. The plant material (young 2-year-old olive seedlings) was selected and brought from a crop nursery. The experimentation started by the irrigation of the control plant with a nutrient solution. About the salinity treatment, the tree seedlings received a nutrient solution fortified by the addition of 100mM of NaCl. Four repetitions are being done according to the field capacity. The study covered the variation of the relative water content in leaves as well as the leaf surface, stomata density, stomatal size and the wax rate on the upper foliar epidermis. According to the achieved results, the RWC leaf area and stomatal density of the treated plants decreased compared to the control. On the other hand, the wax level increases in the case of salt stress compared to the control, both for the grafted plants and for the plants not grafted.