biologia plantarum

Biologia plantarum 37:577, 1995 | DOI: 10.1007/BF02908842

Peroxidase activities of two rice cultivars differing in salinity tolerance as affected by proline and NaCl

S. Lutts¹, G. Guerrier²

¹ Laboratoire de Cytogénétique, Université Catholique de Louvain, Louvain-la-Neuve, Belgium

² Groupe de Biochimie et de Biologie Moléculaire Végétales, Université d'Angers, Angers Cedex, France

Proline content, ion accumulation, cell wall and soluble peroxidase activities were determined in control and salt-treated calli (150 nM NaCl) and whole plants (30 mM NaCl) of two rice cultivars (salt sensitive cv. IKP and salt tolerant cv. Aiwu). Under salinity, the highest accumulation of Na⁺, Cl^- and proline occurred in calli, roots and younger leaves of cv. IKP, coupled with the highest decrease in K⁺ content; accumulations of Na⁺ and Cl^- were restricted to older leaves in cv. Aiwu. Relative growth rates of calli and roots or shoots from both cultivars were not linked to peroxidase activities. High concentrations (1 M) of exogenously applied glycerol did not inhibitin vitro activities of soluble peroxidase extracted from control and salt-treated calli or plants. Conversely, 35-55% (in cv. IKP) or 60-80% (in cv. Aiwu) of soluble peroxidase activities were found in presence of isosmotic proline concentration. There were no differences between proline and glycerol effects onin vitro cell wall peroxidase activities.

Keywords: callus culture; glycerol; Oryza sativa

Received: May 16, 1995; Accepted: July 11, 1995; Published: December 1, 1995  Show citation