Screening of Salt Tolerant Eucalyptus Clones Based on Physio-Morphological and Biochemical Responses Using Grey Relational Analysis

ABSTRACT The salinity of the soil affects crop productivity. Approximately 20% of the total cropland and 33% of irrigated agricultural areas are salinized worldwide. Therefore, saline barren areas require plants that are tolerant of high saline levels. The objective of the current study is to investigate Eucalyptus clones that can thrive in high saline conditions. To achieve this goal, fifty Eucalyptus clones (E. camaldulensis, E. tereticornis) were irrigated with saline water (120 mM NaCl and 50 mM Na2SO4, electrical conductivity ≥20 dS ) for 3 months. To screen salt-tolerant clones, physiological, biochemical, and growth responses of clones were measured. The best performing clones under salt stress were chosen using Grey Relational Analysis (GRA), a Multiple Attribute Decision-Making (MADM) model, which is a novel approach to deal with this kind of screening study. As a result, the rank of (tolerant, moderate, and susceptible) clones was calculated, based on Grey Relational Grade (GRG). The value of GRG was based on the physio-morphological and biochemical responses of clones, indicating their greater ability to withstand saline stress. Results of this study suggest some salt-tolerant clones for the utilization of salt-affected locations to grow Eucalyptus plants, which may help to increase forest sustainability.