Akademik Veri Yönetim Sistemi
JOURNAL OF CROP HEALTH, sa.1, 2025 (SCI-Expanded)
With the increasing impact of global warming, drought has become one of the most critical stress factors affecting plant growth and productivity. The objective of this study was to investigate the morphological, physiological, biochemical, and molecular responses of 21 different pepper genotypes under conditions of water deficit. Water deficit treatments were applied in during the seedling period using two irrigation levels (100 and 60% of field capasity). The water deficit conditions resulted in reduction in the growth parameters such as fresh and dry weight, and leaf area. Furthermore, there was an increase in malondialdehyde (MDA) levels, while tissue water content, photosynthetic activity, transpiration, CO2 levels, stomatal conductance, and chlorophyll content decreased. The water deficit led to an increase in the levels of hydrogen peroxide (H2O2), abscisic acid, proline and sucrose content, as well as an enhancement in the activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). The expression levels of genes associated with drought response were quantified using quantitative reverse transcription polymerase chain reaction (qRT-PCR), revealing significant inter-genotypic variations. In particular, antioxidant enzyme genes CaSOD and CaCAT, responsible for scavenging reactive oxygen species (ROS), exhibited different expression levels among genotypes. Downregulation of CaDHN3 and aquaporin (AQP) gene levels and increased expression of CaDRT1 gene were observed under drought conditions. These findings underline the significant diversity in drought stress tolerance mechanisms observed in pepper genotypes. The study offers crucial insights into the morphological, physiological, biochemical, and molecular responses of pepper plants to drought, establishing a foundation for future research aimed at enhancing drought resilience in pepper plants.