Akademik Veri Yönetim Sistemi
Turkish Journal of Agriculture and Forestry, cilt.47, sa.5, ss.676-687, 2023 (SCI-Expanded)
Salinity is a major environmental stress affecting the growth and development of plants. Saline soils limit crop productivity, resulting in economic losses by compromising morpho-physiological and yield attributes of plants. However, the exogenous application of different plant growth regulators (PGRs) helps to ameliorate the negative effects of salinity. A study was carried out to explore the impact of foliar applications of different PGRs i.e. Salicylic Acid (SA) 250µM, Thiourea (TU) 10mM, dry Moringa Leaf Extract (MLE) 10% and Proline 1µM to mitigate salt stress (NaCl 120mM) in medicinally important plant, Plantago ovata. Salinity hampered shoot length, root and shoot dry matter, fresh weight as well as number of leaves. However, foliar application of PGRs helped to improve various growth attributes like total number of leaves per plant, root length, shoot length, root fresh weight, root dry weight, shoot fresh weight, and shoot dry weight. Moreover, biochemicals i.e. hydrogen peroxide (H2O2) and malondialdehyde (MDA) were substantially increased under salt stress indicating increased reactive oxygen species (ROS). In response to ROS, antioxidants were found to be upregulated when the expression of antioxidant genes like catalase (CAT), Glutathione-S-transferase (GST), and Glutathione Reductase (GR) were analyzed under salinity stress. However, the expression of GR, CAT, and GST was further enhanced after the application of PGRs. Their expression was many folds higher (GR up to 7.4, CAT up to 9.5, and GST up to 7.9 folds higher) in salt-subjected plants as compared to control, suggesting their role in salt stress tolerance. It is concluded that foliar application of PGRs particularly TU and MLE improved morphological parameters and may be recommended for improved growth of plants under salinity stress.