Humic Acid Effect on Catalase Activity and the Generation of Reactive Oxygen Species in Corn (Zea mays)

• Published in: Bioscience, biotechnology, and biochemistry Vol. 75; no. 1; pp. 70 - 74
• Main Authors: CORDEIRO, Flávio Couto, SANTA-CATARINA, Claudete, SILVEIRA, Vanildo, SOUZA, Sonia Regina de
• Format: Journal Article
• Language: English
• Published: Tokyo Japan Society for Bioscience, Biotechnology, and Agrochemistry 01.01.2011; Japan Society for Bioscience Biotechnology and Agrochemistry; Oxford University Press
• Subjects: auxins; Biological and medical sciences; catalase; Catalase - metabolism; corn; enzyme activity; Fundamental and applied biological sciences. Psychology; growth root; humic acid; humic acids; Humic Substances; lateral roots; nitrate nitrogen; Nitrates - pharmacology; nitric oxide; Nitric Oxide - metabolism; nitroprusside; Oxisols; Plant Roots - drug effects; Plant Roots - enzymology; Plant Roots - growth & development; Plant Roots - metabolism; reactive oxygen species; Reactive Oxygen Species - metabolism; root growth; second messengers; Zea mays; Zea mays - drug effects; Zea mays - enzymology; Zea mays - growth & development; Zea mays - metabolism; Monocotyledones; Oxygen; Zea mays; Root; Enzyme; Growth; Corn; growth root; humic acid; Peroxidases; Catalase; Gramineae; Nitric oxide; Angiospermae; reactive oxygen species; Spermatophyta; Oxidoreductases
• ISSN: 0916-8451; 1347-6947; 1347-6947
• DOI: 10.1271/bbb.100553

Humic acids (HAs) have positive effects on plant physiology, but the molecular mechanisms underlying these events are only partially understood. The induction of root growth and emission of lateral roots (LRs) promoted by exogenous auxin is a natural phenomenon. Exogenous auxins are also associated with HA. Gas nitric oxide (NO) is a secondary messenger produced endogenously in plants. It is associated with metabolic events dependent on auxin. With the application of auxin, NO production is significantly increased, resulting in positive effects on plant physiology. Thus it is possible to evaluate the beneficial effects of the application of HA as an effect of auxin. To investigate the effects of HA the parameters of root growth, Zea mays was studied by evaluating the application of 3 mM C L −1 of HA extracted from Oxisol and 100 μM SNP (sodium nitroprusside) and the NO donor, subject to two N-NO 3 − , high dose (5.0 mM N-NO 3 − ) and low dose (5.0 mM N-NO 3 − ). Treatments with HA and NO were positively increased, regardless of the N-NO 3 − taken, as assessed by fresh weight and dry root, issue of LRs. The effects were more pronounced in the treatment with a lower dose of N-NO 3 − . Detection of reactive oxygen species (ROS) in vivo and catalase activity were evaluated; these tests were associated with root growth. Under application of the bioactive substances tested, detection of ROS and catalase activity increased, especially in treatments with lower doses of N-NO 3 − . The results of this experiment indicate that the effects of HA are dependent on ROS generation, which act as a messenger that induces root growth and the emission of LRs.