COMPARISON OF TWO MOST COMMONLY USED SCREENING TECHNIQUES FOR SALT TOLERANCE IN CROP PLANTS

A comparison to test the consistencies and discrepancies of two most commonly used screening techniques (soil and hydroponic) for salt tolerance in crop plants were examined. In this regard, physiological responses of four sunflower genotypes i.e. Hysun-33, Hysun-39 (known moderately salt tolerant) S.28111 and SF0049 (unreported genotypes) growing in soil filled pots and hydroponics were observed. This study was carried out under greenhouse condition in complete randomize design, plants were treated with 75, 125 and 175 mM NaCl concentrations. Stress was applied to the plants in aliquot levels 30 DAS and plants were harvested 44 DAS for further analysis. Some photosynthetic traits; chlorophyll fluorescence, chlorophyll contents, stomatal conductance and relative water content were analysed. Plants grown in a pot experiment had higher PIabs, stomatal conductance, photosynthetic pigments and hence higher plant fresh weight as compared to hydroponic plants. Despite differences in techniques, results revealed that both systems have shown almost similar trends in physiological traits of tested genotypes under saline environment. A significant correlation in performance index (PIabs), RWC, stomatal conductance, proline contents and total carotenoids was found. Physiological assessment and their reliability of salt tolerance in crop plants using both experimental systems were discussed.