Open AccessEffects of melatonin on the sugar metabolism and antioxidative response to excess nitrate stress in lettuce seedlings
Author(s) -
Xiaoting Zhou,
Yao Zhang,
Juzhi Deng,
Zhongli Jiang,
Zhimin He,
Zhirong Zou
Publication year - 2019
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.179
H-Index - 26
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/358/2/022085
Subject(s) - sucrose , melatonin , sucrose phosphate synthase , chemistry , nitrate , sugar , metabolism , fructose , nitrate reductase , hydrogen peroxide , biochemistry , sucrose synthase , enzyme , invertase , food science , biology , endocrinology , organic chemistry
Water and soil pollution by nitrate has caused severe impact to environment, especially the inhibition of plant growth due to the excess nitrate stress. Although previous studies reported the melatonin could mitigate injury of plants in response to excess nitrate stress, the alleviation mechanism of melatonin is still unclear. In this study, lettuce seedlings were used as materials, and the main sugar content, sucrose synthesis and metabolism related enzymes as well as ROS metabolism were investigated. There were dramatic changes in sucrose, glucose and fructose content under excess nitrate stress. Exogenous melatonin further increased the sugar content mentioned above, and melatonin increased some sucrose synthesis and metabolism related enzymes under excess nitrate stress, including sucrose phosphate synthase and acid invertase, enhancing sucrose synthesis and metabolism ability. In addition, the content of malondialdehyde and hydrogen peroxide was increased by excess nitrate stress, while inhibited at presence of melatonin. The activities of SOD and POD were also increased by exogenous melatonin in response to excess nitrate stress. In a conclusion, it is suggested that there is a cross-talk between sugar and ROS scavenging pathway under excess nitrate stress, which is enhanced by melatonin, thus promoting the lettuce plants resistance to stress.