title: γ-Aminobutyric Acid Imparts Partial Protection from Salt Stress Injury to Maize Seedlings by Improving Photosynthesis and Upregulating Osmoprotectants and Antioxidants.
abstract: γ-Aminobutyric acid (GABA) has high physiological activity in plant stress physiology. This study showed that the application of exogenous GABA by root drenching to moderately (MS, 150 mM salt concentration) and severely salt-stressed (SS, 300 mM salt concentration) plants significantly increased endogenous GABA concentration and improved maize seedling growth but decreased glutamate decarboxylase (GAD) activity compared with non-treated ones. Exogenous GABA alleviated damage to membranes, increased in proline and soluble sugar content in leaves, and reduced water loss. After the application of GABA, maize seedling leaves suffered less oxidative damage in terms of superoxide anion (O2·-) and malondialdehyde (MDA) content. GABA-treated MS and SS maize seedlings showed increased enzymatic antioxidant activity compared with that of untreated controls, and GABA-treated MS maize seedlings had a greater increase in enzymatic antioxidant activity than SS maize seedlings. Salt stress severely damaged cell function and inhibited photosynthesis, especially in SS maize seedlings. Exogenous GABA application could reduce the accumulation of harmful substances, help maintain cell morphology, and improve the function of cells during salt stress. These effects could reduce the damage to the photosynthetic system from salt stress and improve photosynthesis and chlorophyll fluorescence parameters. GABA enhanced the salt tolerance of maize seedlings.
authors.affiliation: College of Agriculture, Northeast Agricultural University, Harbin 150030, P.R. China.
authors.forename: Yongchao
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Agriculture, Northeast Agricultural University, Harbin 150030, P.R. China.|The Observation Experiment Station of Ministry of Agriculture for Crop Cultivation Science in Northeast Area, Harbin 150030, P.R. China.
authors.forename: Wanrong
authors.initials: W
authors.lastname: Gu
authors.affiliation: College of Agriculture, Northeast Agricultural University, Harbin 150030, P.R. China.|Heilongjiang Academy of Land Reclamation Sciences, Harbin 100030, P.R. China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Meng
authors.affiliation: College of Agriculture, Northeast Agricultural University, Harbin 150030, P.R. China.
authors.forename: Tenglong
authors.initials: T
authors.lastname: Xie
authors.affiliation: College of Agriculture, Northeast Agricultural University, Harbin 150030, P.R. China.
authors.forename: Lijie
authors.initials: L
authors.lastname: Li
authors.affiliation: College of Agriculture, Northeast Agricultural University, Harbin 150030, P.R. China.|The Observation Experiment Station of Ministry of Agriculture for Crop Cultivation Science in Northeast Area, Harbin 150030, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Agriculture, Northeast Agricultural University, Harbin 150030, P.R. China.|The Observation Experiment Station of Ministry of Agriculture for Crop Cultivation Science in Northeast Area, Harbin 150030, P.R. China.
authors.forename: Shi
authors.initials: S
authors.lastname: Wei
mesh_terms: D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D064587:Osmoregulation; D018384:Oxidative Stress; D010641:Phenotype; D010788:Photosynthesis / Q000187:drug effects; D018515:Plant Leaves / Q000378:metabolism; D055049:Salt Tolerance / Q000187:drug effects; D036226:Seedlings / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological / Q000187:drug effects; D003313:Zea mays / Q000187:drug effects / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D002734:Chlorophyll; D005680:gamma-Aminobutyric Acid