The effect of exogenous calcium application on reducing drought stress damages in pepper grown in in vitro conditions

Capsicum annum L. used in the study is an important species for the country and world economy, especially with its use in the food and pharmaceutical industry. The seeds of Hilvan and Inan (Capsicum annuum L.) pepper cultivars were sown on MS basic medium with 3% sucrose and 0.7% agar added. Polyethylene glycol (3 g.L-1 PEG) and/or calcium (330 mg.L-1 CaCl2) at different concentrations were applied to create drought stress. It was left to germination and seedling development in the plant growth room at 16 hours light/8 hours dark photoperiod, 25±2 0C temperature, and 45% humidity conditions. At the end of the 5th week, the seedlings were harvested according to the randomized blocks trial design, morphological measurements (root-shoot length, fresh and dry weight) and physiological-biochemical analyzes (photosynthetic pigment substance, total protein, total phenolic substance, MDA, proline amounts and antioxidant activities) were performed on the seedlings. It has been determined that drought stress affects both plant varieties negatively, and this effect is alleviated by exogenous calcium applications. It suggests that especially low-concentration exogenous calcium applications can be used in plant cultivation under water deficiency conditions.