Light intensity influences variations in the structural and physiological traits in the leaves of Iris pumila L

Ambient light significantly influences the structural and physiological characteristics of Iris pumila leaves. A random sample of Iris clones native to an exposed site at the Deliblato Sands, Serbia was partially covered with a neutral screen that transmitted 35% of daylight, so that each clone experienced reduced and full sunlight at the same time. The sun-exposed leaves were significantly thicker, had greater stomatal density, exhibited higher lipid peroxidation, increased activities of SOD, APX, CAT enzymes and higher contents of non-enzymatic antioxidants (anthocyanins and phenols) and water deficit relative to shade-leaves. The activities of GR, GPX, and GST enzymes was unaffected by the irradiance level.