Melatonin enhanced oilseed rape growth and mitigated Cd stress risk: A novel trial for reducing Cd accumulation by bioenergy crops

Saiqa Menhas; Xijia Yang; Kashif Hayat; Amjad Ali; Esmat F Ali; Muhammad Shahid; Sabry M Shaheen; Jörg Rinklebe; Sikandar Hayat; Pei Zhou

doi:10.1016/j.envpol.2022.119642

Melatonin enhanced oilseed rape growth and mitigated Cd stress risk: A novel trial for reducing Cd accumulation by bioenergy crops

Environ Pollut. 2022 Sep 1:308:119642. doi: 10.1016/j.envpol.2022.119642. Epub 2022 Jun 15.

Authors

Saiqa Menhas¹, Xijia Yang¹, Kashif Hayat¹, Amjad Ali², Esmat F Ali³, Muhammad Shahid⁴, Sabry M Shaheen⁵, Jörg Rinklebe⁶, Sikandar Hayat⁷, Pei Zhou⁸

Affiliations

¹ School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, PR China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Affairs, Shanghai, China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, 800 Dongchuan Rd, Shanghai, 200240, China.
² School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
³ Department of Biology, College of Science, Taif University, P.O. Box 11099, Taif, 21944, Saudi Arabia.
⁴ Department of Environmental Sciences, COMSATS University Islamabad, Vehari Campus, Vehari, 61100, Pakistan.
⁵ University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany; King Abdulaziz University, Faculty of Meteorology, Environment, and Arid Land Agriculture, Department of Arid Land Agriculture, Jeddah, 21589, Saudi Arabia; International Research Centre of Nanotechnology for Himalayan Sustainability (IRCNHS), Shoolini University, Solan, 173212, Himachal Pradesh, India.
⁶ University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water- and Waste-Management, Laboratory of Soil- and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany.
⁷ College of Landscape Architecture, Nanjing Forestry University, Nanjing, PR China.
⁸ School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, PR China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Affairs, Shanghai, China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, 800 Dongchuan Rd, Shanghai, 200240, China. Electronic address: peizhousjtu@163.com.

PMID: 35716896
DOI: 10.1016/j.envpol.2022.119642

Abstract

Melatonin (M) is a pleiotropic molecule that improves plant growth and increases heavy metal tolerance. The role of M for improving plant growth and tolerance under cadmium (Cd) stress, and mitigation of Cd-induced toxicity has not yet been sufficiently examined. Therefore, here we conducted a glasshouse experiment to explore the influence of various M dosages on Cd detoxification and stress-tolerance responses of Brassica napus under high Cd content (30 mg kg^-1). The effects of M on the modulation of Cd tolerance in B. napus plants have been investigated using various growth attributes, Cd accumulation and tolerance indices, and secondary metabolic parameters. We found that Cd stress inhibited root growth (by 11.9%) as well as triggered reactive oxygen species accumulation (by 31.2%) and MDA levels (by 18.7%); however, exogenous M substantially alleviated the adverse effect of oxidative stress by decreasing levels of H₂O₂ (by 38.7%), MDA (by 13.8%) and EL (by 1.8%) in the Cd-stressed plants, as compared to the M-untreated plants (control). Interestingly, exogenous M reduced Cd accumulation in roots (∼48.2-58.3-fold), stem (∼2.9-5.0-fold) and leaves (∼4.7-6.6-fold) compared to control plants, which might be due to an M-induced defense and/or detoxification response involving a battery of antioxidants. Overall, addition of the exogenous M to the Cd-stressed plants profoundly enhanced Cd tolerance in B. napus relative to control plants. These results suggested the biostimulatory role (at the physiological and molecular level) of M in improving growth, Cd tolerance, and Cd detoxification in B. napus, which indicate the potentiality of M for green remediation of Cd contaminated soils. This green trial would provide a reference for producing renewable bioenergy crops under Cd stress in contaminated soils. However, these recommendations should be verified under field conditions and the potential mechanisms for the interaction between Cd and M should be explicitly explored.

Keywords: Bioactive compounds; Plant growth and development; Rapeseed; Reducing toxic metals stress.

MeSH terms

Antioxidants / metabolism
Antioxidants / pharmacology
Brassica napus*
Cadmium / analysis
Crops, Agricultural / metabolism
Hydrogen Peroxide / metabolism
Melatonin* / metabolism
Melatonin* / pharmacology
Plant Roots / metabolism
Soil
Soil Pollutants* / metabolism

Substances

Antioxidants
Soil
Soil Pollutants
Cadmium
Hydrogen Peroxide
Melatonin