5-Aminolevulinic acid modulates antioxidant defense systems and mitigates drought-induced damage in Kentucky bluegrass seedlings.
Drought stress occurs frequently and severely as a result of global climate change, and it exerts serious effects on plants. 5-Aminolevulinic acid (5-ALA) plays a crucial role in conferring abiotic stress tolerance in plants. To enhance the drought tolerance of turfgrass and investigate the effects of 5-ALA on antioxidant metabolism and gene expression under drought stress conditions, exogenous 5-ALA was applied by foliar spraying before Kentucky bluegrass (Poa pratensis L.) seedlings were exposed to drought [induced by 10% polyethylene glycol (PEG)] stress for 20 days. 5-ALA pretreatment increased turf quality (TQ) and leaf relative water content (RWC) while reducing reactive oxygen species (ROS) production including H2O2content and O2•-generation rate, lipoxygenase (LOX) activity, and malondialdehyde (MDA) content under drought stress. 5-ALA pretreatment maintained ascorbate (AsA) and glutathione (GSH) contents and the ASA/DHA and GSH/GSSG ratios at high levels, and it enhanced the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione peroxidase (GPX), dehydroascorbate reductase (DHAR), and glutathione reductase (GR), which are crucial for scavenging drought-induced ROS. In addition, 5-ALA upregulated the relative expression levels of Cu/ZnSOD, APX, GPX, and DHAR but downregulated those of CAT and GR under drought stress. These results indicated that the application of 5-ALA might improve turfgrass quality and promote drought tolerance in Kentucky bluegrass through reducing oxidative damage and increasing non-enzyme antioxidant levels and antioxidant enzyme activity at transcriptional and posttranscriptional levels.
Key Laboratory of Grassland Ecosystem of Ministry of Education, College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China.
Kuiju
K
Niu
Academy of Animal Sciences and Veterinary, Qinghai University, Xining, 810016, People's Republic of China.
Xiang
X
Ma
Academy of Animal Sciences and Veterinary, Qinghai University, Xining, 810016, People's Republic of China.
Guoling
G
Liang
Key Laboratory of Grassland Ecosystem of Ministry of Education, College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China. mahl@gsau.edu.cn.
Huiling
H
Ma
Academy of Animal Sciences and Veterinary, Qinghai University, Xining, 810016, People's Republic of China.
Zhifeng
Z
Jia
Academy of Animal Sciences and Veterinary, Qinghai University, Xining, 810016, People's Republic of China.
Wenhui
W
Liu
College of Horticulture, South China Agricultural University, Guangzhou, 510642, People's Republic of China.
Qianqian
Q
Yu
D000975:Antioxidants / Q000378:metabolism; D060387:Ascorbate Peroxidases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D055864:Droughts; D005980:Glutathione Reductase / Q000378:metabolism; D007982:Levulinic Acids / Q000494:pharmacology*; D015227:Lipid Peroxidation; D018384:Oxidative Stress; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D031785:Poa / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D017382:Reactive Oxygen Species; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D000622:Aminolevulinic Acid
D000975:Antioxidants; D060387:Ascorbate Peroxidases; D002374:Catalase; D005980:Glutathione Reductase; D007982:Levulinic Acids; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D000622:Aminolevulinic Acid
5-Aminolevulinic acid; Antioxidant defense system; Drought stress; Kentucky bluegrass; Mitigation