MORPHOLOGICAL AND PHYSIOLOGICAL RESPONSE OF SPINACH PLANTS TO WATER STRESS

Abstract

The effects of different water stress (control, low, moderate and severe) on some morphological and physiological characteristics of spinach plants were evaluated. The results showed that water stress strongly affects spinach plant growth and metabolism. The increasing water stress decreased the leaf area, petiole length and biomass accumulation, resulting in dramatically lower spinach yields. Photosynthetic pigment contents increased in response to low and moderate level water stress; however, under severe stress conditions their content started to decrease. The increase in water stress also resulted in a higher proline accumulation as well as total phenolic and flavonoid contents. These results lead to the conclusion that spinach plants could produce protective macromolecules and antioxidants in large quantities even under severe drought conditions, suggesting that spinach can be considered a drought-tolerant plant species from a survival point of view.