Differential superoxide dismutase expression in ryegrass cultivars in response to short term aluminium stress

• Published in: Plant and soil 2012-01, Vol.350 (1-2), p.353-363
• Main Authors: Cartes, Paula, McManus, Michael, Wulff-Zottele, Cristián, Leung, Susanna, Gutiérrez-Moraga, Ana, de la Luz Mora, María
• Format: Article
• Language: English
• Subjects: Acidic soils; Agronomy. Soil science and plant productions; Aluminum; Animal, plant and microbial ecology; Antioxidants; Biological and medical sciences; Biomedical and Life Sciences; Botanical research; Cultivars; Ecology; Enzymes; Fundamental and applied biological sciences. Psychology; Gene expression; General agronomy. Plant production; Genes; Genetic aspects; Genetic research; Genetics and breeding of economic plants; Grasses; Health aspects; Hydroponics; Life Sciences; Lipid peroxidation; Lipids; Mitochondria; Oxidation; Oxidative stress; Pasture; Peroxidation; Phylogeny; Physiological aspects; Plant Physiology; Plant roots; Plant Sciences; Plant-soil relationships; Plants; Protein isoforms; Regular Article; Roots; Ryegrasses; Soil; Soil Science & Conservation; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Soils (acid); Stress analysis; Superoxide; Superoxide dismutase; Superoxides; Toxicity; Zinc
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-011-0919-3

Background and aims Aluminium (Al) toxicity limits pasture production in acidic soils, and there is evidence that antioxidant enzymes such as superoxide dismutase (SOD) play a key role against Al-induced oxidative stress. We have investigated (i) the relationship between Al-toxicity and oxidative damage as well as the time-course of SOD activity and (ii) the expression profiles of two SOD isoforms in the roots of two ryegrass cultivars. Methods Jumbo (Al-sensitive) and Nui (Al-semi-tolerant) ryegrass cultivars were cultured hydroponically with 0 or 0.2 mM Al. Roots were colleted during 48 h to determine Al uptake, lipid peroxidation, SOD activity and the expression of LpCu/Zn-SOD and LpFe-SOD isolated genes. Results LpCu/Zn-SOD and LpFe-SOD were classified phylogenetically as putative mitochondrial and plastidial SODs, respectively. Although Al accumulation did not differ between the two cultivars, lipid peroxidation increased 2.2-fold in Jumbo but only scarcely in Nui by the end of the time-course. An early response in terms of total SOD activity and differential expression of LpCu/Zn-SOD and LpFe-SOD genes occurred in both cultivars after Al treatment. Conclusions SOD isoforms were up-regulated over a longer period in Nui compared with Jumbo, leading finally to a greater protection in roots against the short term Al-toxicity.