Effects of U on the growth, reactive oxygen metabolism and osmotic regulation in radish (Raphanus sativus L.)

• Published in: Environmental science and pollution research international 2022-08, Vol.29 (36), p.55081-55091
• Main Authors: Wu, Guo, Chen, Xi, Zheng, Ting, Xiao, Pi-xian, Zhong, Ning-ying, Yang, Xiu-lin, Li, Yi, Li, Wei
• Format: Article
• Language: English
• Subjects: Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Catalase; Detoxification; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Germination; Membrane permeability; Metabolism; Oxidative stress; Oxygen metabolism; Peroxidase; Poisons; Radioisotopes; Radishes; Raphanus sativus; Research Article; Roots; Seedlings; Seeds; Stress response; Sugar; Superoxide dismutase; Turgor; Uranium; Waste Water Technology; Water Management; Water Pollution Control
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-022-19803-w

Uranium (U) is a non-essential and toxic element, so it is necessary to study the physiological mechanism of plant response to U stress. The present study evaluated the growth status, reactive oxygen metabolism and osmotic regulation system in radish ( Raphanus sativus ) under U stress (0, 25, 50 and 100 μM). The results showed that U had no significant effect on the germination of radish seeds but inhibited the growth of seedlings, such as reduced root activity and increased plasma membrane permeability. U is mainly distributed in radish roots, so it poisons the roots more than the aboveground parts. When U concentration was 25 μM, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activities in radish were increased to cope with the oxidative stress caused by U stress, and the accumulation of proline and soluble sugar was increased to maintain cell turgor. However, under high concentration (100 μM), the damage of radish root was serious; thus, the SOD, CAT and soluble sugar could not respond to U stress. In conclusion, the identification and characterization of U-stress responses in genuine U-tolerant plants would improve our knowledge on the detoxification of this radionuclide.