Differential Response of Bean (Phaseolus vulgaris L.) Roots and Leaves to Salinity in Soil and Hydroponic Culture

Abstract

The present study aimed to investigate the response of common bean (Phaseolus vulgaris L. Volare) roots and leaves to salinity in different growth mediums (soil and hydroponic culture) through physiologic and biochemical analyses. The relative water content (RWC) and total chlorophyll (CHL) content decreased with 300 mM NaCl treatment in both cultures but did not change with 150 mM treatment in soil culture. Similarly, the malondialdehyde (MDA) content did not change with 150 mM treatment in soil culture, whereas it increased in all other treatments. The highest increase in hydrogen peroxide (H₂O₂) content was observed with 300 mM treatment in hydroponic culture. The highest increase in superoxide dismutase (SOD) activity was observed in plant leaves in the hydroponic culture. Catalase (CAT) activity did not change with 150 mM treatment in soil culture but decreased with 300 mM treatment in both cultures. Ascorbate peroxidase (APX) activity decreased in all treatments, except in the roots in the hydroponic culture. The Na⁺ and Cl^- contents were higher in the hydroponic culture than in the soil culture. Salt stress induced more serious oxidative damage in the hydroponic culture compared to the soil culture.