Growth, nutrient acquisition, and physiological responses of three olive cultivars to induced salt stress

ABSTRACT

Three olive (Olea europaea L.) cultivars Nabali Baladi (NB), Nabali Muhassan (NM), and Grossi Di'Espagna (GE) were evaluated under salt stress. Seedlings were treated with salinity induced by a 3:1 ratio of calcium chloride and sodium chloride to four concentration levels measured as electrical conductivity (EC) [1.2, 4.1, 7.0, and 14.0 dS/m] for 122 days. Olive seedlings varied in their response to salinity. In all treatments, NB had the highest root; stem and leaf dry weights had among the highest total plant dry weights, specific stem length (SSL) and relative water content (RWC). NB seedlings maintained the highest stomatal conductance at 7.0 dS/m and highest chlorophyll index at 14.0 dS/m. Olive seedlings that tolerated salt tolerance developed mechanisms of nutrient acquisition and distribution in the organs, by storing minimal amounts of sodium (Na⁺) and chloride (Cl⁻) in the stems and loading the most in the leaves and roots.

KEYWORDS:

• nutrient acquisition
• olive
• salt stress
• water relations

Acknowledgments

The authors highly appreciate the generous support of Jordan Ministry of Agriculture, and the National Center for Agricultural Research and Extension for providing them with the olive plants and for allowing them to use their facilities and equipment. In addition, they are thankful to Dr. Hani Ghosheh for reviewing this work.