Potentiality of Melatonin for Reinforcing Salinity Tolerance in Sorghum Seedlings via Boosting Photosynthetic Pigments, Ionic and Osmotic Homeostasis and Reducing the Carbonyl/Oxidative Stress Markers

• DOI: 10.1007/s42729-024-01830-w
• Publication Date: 2024-06-11T09:01:56Z
• Authors: Nesma M. Helal; Hani S. Saudy; Maha M. A. Hamada; Ahmed Abou El-Yazied; Hany G. Abd El-Gawad; Soumya Mukherjee; Salem Mesfir Al-Q...; Nadi Awad Al-Harbi; Salwa M. El-Sayed; Mohamed F. M. Ibr...
• Keywords: Malondialdehyde

Abstract Salinity stress has become a major threat to worldwide crop production. Exogenous melatonin (MT) appeared as promising treatment against salt in several plant species. However, MT effect on the tolerance of sorghum plants under different saline conditions (moderate and severe) remains ambiguous. This study was carried out explore impact (0, 50, 100 200 µM) foliar application seedlings grown moderate severe using sodium chloride, NaCl (75 150 µM NaCl). treatments were applied solution sand medium pots. The results demonstrated that rising salinity level negatively affected growth, photosynthetic pigments (chlorophylls carotenoids), leaf water status ionic homeostasis (sodium, potassium, calcium ions). Applied-MT specifically at or enhanced osmotic balance, cell membrane stabilizing relative content. These effects associated with an obvious restriction hydrogen peroxide, lipid peroxidation (malondialdehyde content) methylglyoxal. Moreover, antioxidant activities peroxidase, catalase, superoxide dismutase, ascorbate peroxidase enzymes modulated by treatments. Molecular docking modeling assessment illustrated top-ranked confirmations between target enzymes. forms multiple bonds key amino acid residues for glycine (A: 162), tryptophan 41), leucine 165), tyrosine 235) active site peroxidase. alkyl interactions 37), arginine 38) cysteine 168) also contribute its high affinity. Despite is commonly moderately tolerant stress, this confirmed sensitivity wide range early growth stages. Melatonin spraying led improvements various morphological, physiological biochemical mechanisms harmonized together confer resistance salt-stressed seedlings.