Melatonin Application Alleviates Stress-Induced Photosynthetic Inhibition and Oxidative Damage by Regulating Antioxidant Defense System of Maize: A Meta-Analysis

Ihsan Muhammad; Li Yang; Shakeel Ahmad; Ibrahim S M Mosaad; Abdullah Ahmed Al-Ghamdi; Arshad Mehmood Abbasi; Xun-Bo Zhou

doi:10.3390/antiox11030512

Melatonin Application Alleviates Stress-Induced Photosynthetic Inhibition and Oxidative Damage by Regulating Antioxidant Defense System of Maize: A Meta-Analysis

Antioxidants (Basel). 2022 Mar 8;11(3):512. doi: 10.3390/antiox11030512.

Authors

Ihsan Muhammad¹, Li Yang¹, Shakeel Ahmad¹, Ibrahim S M Mosaad², Abdullah Ahmed Al-Ghamdi³, Arshad Mehmood Abbasi^{4

5}, Xun-Bo Zhou¹

Affiliations

¹ Guangxi Colleges and Universities Key Laboratory of Crop Cultivation and Tillage, Agricultural College, Guangxi University, Nanning 530004, China.
² Soil Fertility and Plant Nutrition Research Department, Soil, Water and Environment Research Institute, Agricultural Research Center, Giza 12619, Egypt.
³ Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
⁴ Department of Environmental Sciences, COMSATS University Islamabad, Abbottabad Campus 22060, Pakistan.
⁵ University of Gastronomic Sciences, 12042 Pollenzo, Italy.

Abstract

Melatonin is effective in modulating metabolism and regulating growth and development in many plants under biotic and abiotic stress. However, there is no systematic quantification of melatonin effects on maize growth, gas exchange, chlorophyll content, and the antioxidant defense system. A meta-analysis was conducted on thirty-two currently available published articles to evaluate the effect of stress types, study types, and maize varieties on response ratio (lnRR₊₊) of "melatonin" to "control (no melatonin)" on plant growth, enzyme activities, gas exchange parameters, and photosynthetic pigments. Our findings revealed that melatonin application overall increased plant height, leaf area, root length, fresh and dry root weight and shoot weight, superoxide dismutase (SOD), peroxide (POD), catalase (CAT), ascorbate peroxidase (APX), soluble sugar and protein, photosynthetic rate, stomatal conductance, transpiration rate, chlorophyll, and carotenoid in maize leaf under stress conditions. In contrast, melatonin application decreased the levels of hydrogen peroxide (H₂O₂), superoxide anion (O_2^-), malondialdehyde (MDA), and electrolyte leakage. The categorical meta-analysis demonstrated that melatonin application to chilling stress resulted in higher SOD activity followed by salt stress. Melatonin application to all stress types resulted in higher POD, CAT and APX activities, except Cd stress, which had no effect on POD and decreased CAT by 38% compared to control. Compared to control, melatonin resulted in lower reactive oxygen species (ROS) and electrolyte leakage under no stress, Cd, drought, salt, lead, heat, and chilling stress in all study types (pot, growth chamber, hydroponic, and field), except O₂ content which was not affected in pot and growth chamber studies. It was concluded that melatonin alleviates oxidative damage by improving stress tolerance, regulating the antioxidant defense system, and increasing leaf chlorophyll content compared to control.

Keywords: environmental stress; heavy metals; heterogeneity; maize varieties; melatonin; meta-analysis.

Abstract

Grants and funding