Melatonin Enhances the Tolerance and Recovery Mechanisms in Brassica juncea (L.) Czern. Under Saline Conditions

Bibliographic Details
Title: Melatonin Enhances the Tolerance and Recovery Mechanisms in Brassica juncea (L.) Czern. Under Saline Conditions
Authors: Hee-Soon Park, Elham Ahmed Kazerooni, Sang-Mo Kang, Abdullah Mohammed Al-Sadi, In-Jung Lee
Source: Frontiers in Plant Science, Vol 12 (2021)
Publisher Information: Frontiers Media S.A., 2021.
Publication Year: 2021
Collection: LCC:Plant culture
Subject Terms: salinity, melatonin, antioxidant enzymes, photosynthesis, amino acids, phytohormones, Plant culture, SB1-1110
More Details: Melatonin has been recently known to stimulate plant growth and induce protective responses against different abiotic stresses. However, the mechanisms behind exogenous melatonin pretreatment and restoration of plant vigor from salinity stress remain poorly understood. The present study aimed to understand the effects of exogenous melatonin pretreatment on salinity-damaged green mustard (Brassica juncea L. Czern.) seedlings in terms of oxidative stress regulation and endogenous phytohormone production. Screening of several melatonin concentrations (0, 0.1, 1, 5, and 10 μM) on mustard growth showed that the 1 μM concentration revealed an ameliorative increase of plant height, leaf length, and leaf width. The second study aimed at determining how melatonin application can recover salinity-damaged plants and studying its effects on physiological and biochemical parameters. Under controlled environmental conditions, mustard seedlings were irrigated with distilled water or 150 mM of NaCl for 7 days. This was followed by 1 μM of melatonin application to determine its recovery impact on the damaged plants. Furthermore, several physiological and biochemical parameters were examined in stressed and unstressed seedlings with or without melatonin application. Our results showed that plant height, leaf length/width, and stem diameter were enhanced in 38-day-old salinity-stressed plants under melatonin treatment. Melatonin application obviously attenuated salinity-induced reduction in gas exchange parameters, relative water content, and amino acid and protein levels, as well as antioxidant enzymes, such as superoxide dismutase and catalase. H2O2 accumulation in salinity-damaged plants was reduced by melatonin treatment. A decline in abscisic acid content and an increase in salicylic acid content were observed in salinity-damaged seedlings supplemented with melatonin. Additionally, chlorophyll content decreased during the recovery period in salinity-damaged plants by melatonin treatment. This study highlighted, for the first time, the recovery impact of melatonin on salinity-damaged green mustard seedlings. It demonstrated that exogenous melatonin supplementation significantly improved the physiologic and biochemical parameters in salinity-damaged green mustard seedlings.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 1664-462X
Relation: https://www.frontiersin.org/articles/10.3389/fpls.2021.593717/full; https://doaj.org/toc/1664-462X
DOI: 10.3389/fpls.2021.593717
Access URL: https://doaj.org/article/3f0240435a8e41dfa1c740ae52bb11f7
Accession Number: edsdoj.3f0240435a8e41dfa1c740ae52bb11f7
Database: Directory of Open Access Journals
More Details
ISSN:1664462X
DOI:10.3389/fpls.2021.593717
Published in:Frontiers in Plant Science
Language:English