Effect of strontium on nutrient uptake, physiological parameters, and strontium localization in lettuce

• Published in: Environmental science and pollution research international Vol. 29; no. 23; pp. 34874 - 34886
• Main Authors: Yan, Dong, Ding, Kuke, He, Yingxue, Fan, Li, Che, Yongfei, Zhao, Yingjun, Jiang, Xiaoyan
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2022; Springer Nature B.V
• Subjects: Antioxidants; Antioxidants - pharmacology; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Calcium; Calcium influx; Catalase; Cross-sections; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental science; Food chains; Hydroponics; Iron; Isotopes; Lactuca; Leaves; Localization; Mesophyll; Nutrient concentrations; Nutrient uptake; Nutrients; Peroxidase; Peroxidases; Photosynthesis; Physiological effects; Physiological responses; Physiology; Plant Leaves; Plant Roots; Plant tissues; Research Article; Sampling; Scanning electron microscopy; Sheaths; Strontium; Strontium isotopes; Sulfur; Superoxide Dismutase; Variance analysis; Vegetables; Waste Water Technology; Water Management; Water Pollution Control; Malondialdehyde (MDA); Nutrients; Antioxidant enzyme; Strontium (Sr); SEM–EDX; Glutathione (GSH)
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-021-18108-8

Human activities increase the risk of stable and radioactive strontium (Sr) isotopes entering the environment and food chain. In this study, the effects of Sr on the nutrient uptake and physiological responses of lettuce under different “Sr treatment” concentrations (0, control, 1, 2, 3, 4, and 5 mM) and “times” (7, 14, and 21 day) were studied in a hydroponic system. In addition, the distribution of Sr on the surfaces and cross-sections of lettuce leaves was revealed by scanning electron microscopy with energy-dispersive X-ray (SEM–EDX) analysis. A two-way analysis of variance (ANOVA) method was used to analyze the significance of “Sr treatment,” “time,” and their “interaction.” The results showed that an increase in Sr uptake in lettuce could significantly reduce the uptake of calcium (Ca). The contents of sulfur (S), potassium (K), and iron (Fe) in lettuce leaves showed significant differences with the sampling day. Similarly, the fresh weight of lettuce leaves and roots as well as the photosynthetic pigment contents of lettuce leaves was also significantly different with the sampling day. The activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD)) showed significant differences with the sampling day. The activities of SOD and CAT decreased significantly with the sampling day, while POD increased significantly. The MDA content increased significantly with increasing hydroponic Sr concentration on the 21st day. SEM–EDX analysis showed that the weight percentage of Sr in the vascular bundle sheath in the cross-section of lettuce leaves was relatively higher than that in the mesophyll. This study aids our understanding of the distribution of Sr in lettuce leaf tissues and the effect of Sr on lettuce physiology.