Effect of Cadmium on flag leaf morpho-physiological traits in three Mediterranean hulless barley varieties

In Morocco, the use of phosphate fertilizer in farming system represents a source of cadmium that accumulates in soil and would affect negatively the growth and yield. Cadmium toxicity decreases nutrients and water translocation and absorption, it leads to an increase in oxidative harm, affects the metabolism of plants, and inhibits plant morpho-physiology as well. This experiment was conducted to examine the impacts of various concentrations of Cd (0, 15, 30 mg leg-1) in the flag leaf of three hulless barley varieties: Assiya (Morocco), Tombari (Tunisia), and Gizal30 (Egypt). Several morpho-physiological parameters were measured at vegetative stage encompassing measurements like Flag leaf length (FLL), Flag leaf area (FLA), Flag leaf width (FLW), and Flag leaf dry weight (FLDW), water relative content (RWC), total chlorophyll content (SPAD), and Fluorescence (Fv/Fm). ANOVA analysis showed that all morphological traits (except for FLDW) were primarily affected by the variety effect (>62% of total variance). In contrast, the treatment of Cd largely influenced physiological traits (>90% of total variance). Moreover, the interaction between the two factors was in general of lower importance. Comparison among varieties showed significant differences for all traits. In fact, the Moroccan variety (Assiya) displayed the highest values for physiological and morphological parameters.