biologia plantarum

Biologia plantarum 49:305-308, 2005 | DOI: 10.1007/s10535-005-5308-4

Plant water status, H₂O₂ scavenging enzymes, ethylene evolution and membrane integrity of Cicer arietinum roots as affected by salinity

S. Kukreja¹, A. S. Nandwal^1,*, N. Kumar¹, S. K. Sharma², S. K. Sharma⁴, V. Unvi³, P. K. Sharma⁴

¹ Department of Botany and Plant Physiology, CCS Haryana Agricultural University, Haryana, India

² Department of Soil Science, CCS Haryana Agricultural University, Haryana, India

³ Central Laboratory, CCS Haryana Agricultural University, Haryana, India

⁴ Central Soil Salinity Research Institute, Haryana, India

The chickpea genotype, CSG-8962 was raised in screenhouse to study salinity induced changes in ethylene evolution, antioxidative defence system and membrane integrity in relation to changes in plant water and mineral content. At vegetative stage (60 d after sowing), the plants were exposed to single saline irrigation (0, 2.5, 5.0 and 10.0 dS m^-1). Sampling was done 3 d after saline treatments. The other sets of treated plants were re-irrigated with water and sampled after further 3 d. The Ψ_w of leaf and Ψ_s of leaf and roots decreased from -0.47 to -0.61 MPa, -0.67 to -1.23 MPa and from -0.57 to -0.95 MPa, respectively, with increasing salinity. Similarly, RWC of leaf and roots reduced from 87.5 to 72.3 % and 96.7 to 84.35 %, respectively. The decline in Ψs of roots was mainly due to accumulation of proline and total soluble sugar. With salinity, increase in ethylene evolution, 1-aminocyclopropane-1-carboxylic acid (ACC) content and ACC oxidase activity was reported. Similarly, marked increase in H₂O₂ content (20 - 182 %) and lipid peroxidation (43 - 170 %) was observed. The defense mechanism activated in roots was confirmed by the increased activities of superoxide dismutase (SOD), peroxidase (POX), ascorbate peroxidase (APX), glutathione transferase (GTase), glutathione reductase (GR) and catalase (CAT) but ascorbic acid (AA) content was decreased. About 3-fold increase in Na⁺/K⁺ ratio and 2.5 fold increase in Cl^- content was observed. Upon desalinization, a partial recovery was observed in most of the parameters studied.

Keywords: ascorbic acid; chickpea; lipid peroxidation; mineral content; recovery; water relations

Subjects: 1-aminocyclopropane-1-carboxylic acid (ACC); ascorbate peroxidase; catalase; chickpea, salt stress; Cicer arietinum; ethylene; glutathione reductase; glutathione transferase; hydrogen peroxide; lipid peroxidation; malondialdehyde; membrane integrity, salt stress; osmotic potential; peroxidase; recovery, relative water content; relative water content; root, salt stress; saline irrigation; superoxide dismutase; water potential; water relations

Received: June 1, 2004; Accepted: October 5, 2004; Published: June 1, 2005  Show citation