Effects of lead stress on anti-oxidative enzymes and stress-related hormones in seedlings of Excoecaria agallocha Linn

• Published in: Plant and soil 2013-06, Vol.367 (1/2), p.327-338
• Main Authors: Yan, Zhongzheng, Tam, Nora Fung Yee
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Biological and medical sciences; Biomedical and Life Sciences; Botanical research; Ecological succession; Ecology; Enzymes; Excoecaria agallocha; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Health aspects; Heavy metals; Hormones; Lead; Leaves; Life Sciences; Lipids; Mangrove plants; Nutrient dynamics; Oxidative stress; Plant biology; Plant Physiology; Plant roots; Plant Sciences; Plant-soil relationships; Plants; Regular Article; Sediments; Seedlings; Soil and water pollution; Soil science; Soil Science & Conservation; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Stress (Physiology)
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-012-1467-1

Background and Aims This study aimed to evaluate the responses of anti-oxidative enzymes and stressrelated hormones in E. agallocha to different levels of Pb stresses at different exposure time. Methods The study was carried out in greenhouse, and the pot trials were conducted to investigate the stress responses of root and leaf to Pb exposure in seedlings of E. agallocha. Results Pb stress posed higher toxic effects on root than leaf at day 49. At days 1, 7and 49, the activities of Superoxide dismutase and peroxidases increased significantly, especially in leaves. Significant increases of malondialdehyde content were also observed at day 1 but significant increases of proline were only found at day 49 in leaf. Increases of salicylic acid and jasmonic acid were mainly observed in the leaves at day 1. Conclusions E. agallocha was sensitive to Pb stress and damages, but tended to acclimate to low levels of Pb stresses by increasing and maintaining high levels of SOD and POD activities even at the later stage of exposure (day 49). Increases of endogenous SA and JA concentrations at day 1 might also involve in the plant's tolerance to Pb stress.