Variation of Pigment Content and Antioxidant Enzyme Activites in Pinto Bean (Phaseolus vulgaris L.) Seedlings under Salt Stress

Subject Areas : Journal of Crop Ecophysiology

سجاد Moharramnejad ¹ (PhD. Student of Plant Breeding, University of Mohaggegh Ardabili, Ardabil, Iran)
M. Valizadeh ² (Professor, Department of Plant Breeding and Biotechnology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran)

Received: 2014-06-22 Accepted : 2015-02-28 Published : 2015-04-21

Keywords: Antioxidant enzymes, Salt stress, Pigment content, Polyacrylamide gel,

Abstract :

Effects of salt stress (NaCl) on fresh weight, pigment content and superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT) activities in nine genotypes of pinto bean exposed to two levels of NaCl )0 and 400 mM( were studied. A factorial experiment on the basis of completely randomized design was carried out in laboratory conditions. Salinity stress increased carotenoids in the leaves while it decreased chlorophyll a and total chlorophyll significantly. Salinity reduced by 24.31% fresh weight. Electrophoretic analyses were performed by using 8% slab polyacrylamide gels. For each isozymic band the “density × area” scores onto gels were evaluated by MCID software as enzymatic activity. Three isozymes were observed for each of SOD and POX and one for CAT. Salt stress increased activities of all observed enzymes. Application of salt stress increased activities of SOD1, SOD2 and SOD3. Their activity increment was estimate to be 26.31, 13.89 and 17.64 percent respectively. POX1, POX2 and POX3 activity increment, were also estimated to be48.38, 21 and 43.02 percent respectively. In the case of CAT it was 43.85 percent. Antioxidant enzymes activity increment could be important strategy for reducing the damage caused by oxidative stress.