Changes in Water Relations and Photosynthetic Indices of Olive Self-Rooted Cuttings of Zard cv. in Response to Irrigation Water Salinity and Soil Compaction

Responses of olive self-rooted cuttings of Zard cultivar (Olea europaea L. cv. Zard) to different levels of soil compaction and irrigation water salinity at the field capacity under greenhouse condition were studied. A loamy sand soil passed through a 4.76mm sieve, was poured into the PVC cylinders with diameter of 15cm and then they were compacted to be achieved the desired compaction levels. One-year-old rooted olive cuttings were transplanted into the PVC cylinders. After stabilization of cuttings, cylinders were irrigated by waters having different electrical conductivities at three days intervals, for five months. Some morphological and physiological properties of the olive plants were measured. As the salinity levels of irrigation water increased transpiration, stomatal conductance, photosynthetic rate, relative water content, water potential of stem, temperature difference between leaf and the environment and chlorophyll index decreased, for preserving plant internal water balance. Instantaneous WUE, electrolyte leakage and Na concentration of leaves increased as the salinity levels of irrigation water increased because of the decrease in transpiration and due to the plant’s salinity tolerance mechanisms. The relative water content of leaf, water potential of stem and temperature difference between leaf and environment decreased as the soil compaction increased due to decrease in water uptake. Photosynthetic indices of olive cuttings of Zard cultivar significantly decreased beyond the EC of 8 dS m-1.