Melatonin Mitigates Drought Induced Oxidative Stress in Potato Plants through Modulation of Osmolytes, Sugar Metabolism, ABA Homeostasis and Antioxidant Enzymes
Ahmed Abou El-Yazied,
Mohamed F. M. Ibrahim,
Mervat A. R. Ibrahim,
Ibrahim N. Nasef,
Salem Mesfir Al-Qahtani,
Nadi Awad Al-Harbi,
Fahad Mohammed Alzuaibr,
Abdullah Alaklabi,
Eldessoky S. Dessoky,
Nadiyah M. Alabdallah,
Mohamed M. A. Omar,
Mariam T. S. Ibrahim,
Amr A. Metwally,
Karim. M. Hassan,
Said A. Shehata
Affiliations
Ahmed Abou El-Yazied
Department of Horticulture, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
Mohamed F. M. Ibrahim
Department of Agricultural Botany, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
Mervat A. R. Ibrahim
Department of Biochemistry, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
Ibrahim N. Nasef
Department of Horticulture, Faculty of Agriculture, Suez Canal University, Ismailia 41522, Egypt
Salem Mesfir Al-Qahtani
Biology Department, University College of Tayma, Tabuk University, P.O. Box 741, Tabuk 47512, Saudi Arabia
Nadi Awad Al-Harbi
Biology Department, University College of Tayma, Tabuk University, P.O. Box 741, Tabuk 47512, Saudi Arabia
Fahad Mohammed Alzuaibr
Department of Biology, Faculty of Science, University of Tabuk, P.O. Box 741, Tabuk 71491, Saudi Arabia
Abdullah Alaklabi
Department of Biology, Faculty of Science, University of Bisha, P.O. Box 551, Bisha 61922, Saudi Arabia
Eldessoky S. Dessoky
Department of Biology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia
Nadiyah M. Alabdallah
Department of Biology, College of Science, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia
Mohamed M. A. Omar
Department of Biochemistry, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
Mariam T. S. Ibrahim
Department of Biochemistry, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
Amr A. Metwally
Department of Horticulture, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
Karim. M. Hassan
Department of Horticulture, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
Said A. Shehata
Department of Agricultural Botany, Faculty of Agriculture, Ain Shams University, Cairo 11566, Egypt
The effect of melatonin (MT) on potato plants under drought stress is still unclear in the available literature. Here, we studied the effect of MT as a foliar application at 0, 0.05, 0.1, and 0.2 mM on potato plants grown under well-watered and drought stressed conditions during the most critical period of early tuberization stage. The results indicated that under drought stress conditions, exogenous MT significantly (p ≤ 0.05) improved shoot fresh weight, shoot dry weight, chlorophyll (Chl; a, b and a + b), leaf relative water content (RWC), free amino acids (FAA), non-reducing sugars, total soluble sugars, cell membrane stability index, superoxide dismutase (SOD), catalase (CAT), guaiacol peroxidase (G-POX), and ascorbate peroxidase (APX) compared to the untreated plants. Meanwhile, carotenoids, proline, methylglyoxal (MG), H2O2, lipid peroxidation (malondialdehyde; MDA) and abscisic acid (ABA) were significantly decreased compared to the untreated plants. These responses may reveal the protective role of MT against drought induced carbonyl/oxidative stress and enhancing the antioxidative defense systems. Furthermore, tuber yield was differentially responded to MT treatments under well-watered and drought stressed conditions. Since, applied-MT led to an obvious decrease in tuber yield under well-watered conditions. In contrast, under drought conditions, tuber yield was substantially increased by MT-treatments up to 0.1 mM. These results may imply that under water deficiency, MT can regulate the tuberization process in potato plants by hindering ABA transport from the root to shoot system, on the one hand, and by increasing the non-reducing sugars on the other hand.