Physiological and Biochemical Changes of Pepper Cultivars Under Combined Salt and Drought Stress

Drought and salinity have been considered as environmental problems for plant growth and productivity. This study was performed to investigate growth, biochemical and physiological response to interactive salt and drought stress in pepper seedlings with two different cultivars. We examined three different salinity levels (0, 75 and 150 mM NaCl) and three different irrigation levels (100%, 75% and 50% of the water to reach the field capacity). Drought and salt stress were imposed individually and together on Yalova cv. and Maras cv. pepper (Capsicum annuum L.). Plant growth, tissue electrolyte leakage, stoma conductivity, relative water content, and antioxidants etc. were significantly degraded by treatments. To tolerate stress conditions, pepper seedlings tried to adapt by changing their antioxidant enzyme activity, proline or sugar content. Severe drought stress caused roughly 55% fresh shoot weight loss for Maras cv. and roughly 65% yield loss for Yalova cv. However severe salt stress caused roughly 70% shoot weight loss for Maras and 78% yield loss for Yalova cv., on the other hand, when two stress factors implemented together the fresh shoot weight reduction were 85% for Maras cv. and 83% for Yalova cv.