Exogenous malic acid alleviates cadmium toxicity in Miscanthus sacchariflorus through enhancing photosynthetic capacity and restraining ROS accumulation.
Malic acid (MA) plays an important role in the regulation of plant growth, stomatal aperture, nutrition elements homeostasis and toxic metals tolerance. However, little is known about the effects of exogenous MA on physiological and biochemical responses to toxic metals in plants. To measure the alleviation roles of exogenous MA against cadmium (Cd), we determined the effects of MA on plant growth, net photosynthetic rate (Pn), reactive oxygen species (ROS) accumulation and the activities of anti-oxidant enzymes in the leaves of Miscanthus sacchariflorus (M. sacchariflorus) under Cd stress. The Cd exposure alone significantly inhibited plant growth and Pn, but increased the accumulation of ROS even though the anti-oxidant enzymes were markedly activated in the leaves of M. sacchariflorus. Treatment with MA significantly enhanced plant growth and decreased Cd accumulation accompanied by increasing Pn under Cd stress as compared to Cd stress alone, especially when treatment with high concentration of MA (200μM) was used. In addition, Cd and MA indicated synergistic effects by further increasing the activities and genes expression of partial anti-oxidant enzymes, thus resulting in higher glutathione accumulation and reduction of ROS production. The results showed that application of MA alleviated Cd-induced phytotoxicity and oxidant damage through the regulation of both enzymatic and non-enzymatic anti-oxidants under Cd stress in M. sacchariflorus.
College of Life Sciences, Zhejiang University, Hangzhou 310058, China; State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Linan, Hangzhou 311300, China.
Haipeng
H
Guo
College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
Houming
H
Chen
Academy of Agricultural Sciences of Ningbo City, Ningbo 315040, China.
Chuntao
C
Hong
College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
Dean
D
Jiang
State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Linan, Hangzhou 311300, China. Electronic address: bszheng@zafu.edu.cn.
Bingsong
B
Zheng
D000975:Antioxidants / Q000378:metabolism; D002104:Cadmium / Q000633:toxicity*; D005978:Glutathione / Q000378:metabolism; D008293:Malates / Q000494:pharmacology*; D010788:Photosynthesis / Q000187:drug effects*; D018515:Plant Leaves / Q000187:drug effects / Q000502:physiology; D018517:Plant Roots / Q000187:drug effects / Q000502:physiology; D006109:Poaceae / Q000187:drug effects* / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012989:Soil Pollutants / Q000633:toxicity*
D000975:Antioxidants; D008293:Malates; D017382:Reactive Oxygen Species; D012989:Soil Pollutants; D002104:Cadmium; C030298:malic acid; D005978:Glutathione
Antioxidant system; Cadmium; Gene expression; Malic acid; Miscanthus sacchariflorus; Reactive oxygen species