INFLUENCE OF SALINE STRESS ON GROWTH, GAS EXCHANGE, MINERAL NUTRIENTS AND NON-ENZYMATIC ANTIOXIDATNS IN MUNGBEAN [(VIGNA RADIATA (L.) WILCZEK]

Abstract

The study was conducted to appraise the effect of saline stress on growth, gas exchange, chlorophyll fluorescence, mineral nutrients and non-enzymatic antioxidants in 2 mungbean [Vigna radiata (L.) Wilczek] lines (97001 and 97012). Seeds of each line were sown in sand-filled pots. When the plants were 30 day-old, 2 saline regimes [control (non-saline – full strength Hoagland’s nutrient solution) and 50mM NaCl in Hoagland’s nutrient medium] were applied and maintained 30 days, after which time data for various growth and physiological attributes were recorded. Saline stress markedly reduced shoot fresh and dry weight, shoot length, net CO2 assimilation rate, transpiration rate, stomatal conductance, water use efficiency, leaf and root N contents, and leaf ascorbic acid and phenolic contents in both mungbean lines. In contrast, salt stress significantly enhanced leaf and root Na+ and root Ca2+ contents in both mungbean lines. Saline stress did not alter leaf chlorophyll fluorescence, leaf and root K+ and P and leaf Ca2+ as well as leaf alpha-tocopherol. Overall, line 97001 showed better performance than line 97012 under both saline and non-saline conditions.