Effect of light and benzyladenine on dark-treated growing rice (Oryza sativa) leaves. II. Changes in peroxidase activity

• Published in: Plant and cell physiology 1985, Vol.26 (6), p.987-994
• Main Authors: Reddy, K.P, Subhani, S.M, Khan, P.A, Kumar, K.B
• Format: Article
• Language: English
• Subjects: Benzyladenine; Catalase; dark; enzyme activity; Growth; leaves; Light; Oryza sativa; Peroxidase; Rice (Oryza sativa)
• ISSN: 0032-0781; 1471-9053
• DOI: 10.1093/oxfordjournals.pcp.a077018

Changes in peroxidase activity were studied in the attached first leaf of dark-treated Oryza sativa L. cv. Bala seedlings in response to benzyladenine and light treatments during later periods of leaf growth, prior to maturation. Darkness caused a mild decrease in peroxidase activity; but in illuminated leaves, the enzyme activity was stable at all times. There was a sharp rise in peroxidase activity in dark-treated leaves upon light or benzyladenine application, irrespective of the time of treatment. Benzyladenine treatment to illuminated leaves also caused a rise in peroxidase activity. Exogenous hydrogen peroxide, glycolate and amizol resulted in a rise in peroxidase activity, which was further enhanced by benzyladenine treatment in both light and dark incubated leaves. Proline maintained chlorophyll levels, whereas hydroxyproline caused chlorophyll degradation. Benzyladenine enhanced the proline effect and counteracted the hydroxyproline effect on chlorophyll. Both proline and hydroxyproline increased peroxidase activity in the leaves of light and dark incubated seedlings, and the enzyme activity further increased after benzyladenine treatment.