Carbon Isotope Discrimination in Mango Leaves Under Salt Stress

Abstract

-The aim of this study was to evaluate the response of mango plants (Mangifera indica L) 'Tommy Atkins' cultivar to different NaCl concentrations. In this experiment, plants were grown in pots with washed sand and nutrient solution with 0, 10, 20 and 30 mM NaCl for 120 days. After this period, young leaves from the last growth spurt were harvested in a randomized block design, dried at 65 °C for 72 h and ground in a ball mill. Samples were dried again in an oven at 60 °C for 24 h and then the relative abundance of 13 C and 12 C isotopes was determined using mass spectrometer Sercon 20-20 isotope ratio model. Data were used to determine the carbon isotopic discrimination (Δ). It was concluded that 'Tommy Atkins' mango trees submitted to 30 mmol L -1 NaCl discriminated less 13 C, which may be an indication of salt stress in these plants.

Lima Bean Growth, Leaf Stomatal and Nonstomatal Limitations to Photosynthesis, and 13C Discrimination in Response to Saline Irrigation

“…When CO 2 availability to leaves is reduced by an increased stomatal limitation, C i /C a may decrease. As a result, in a number of plant species under drought or salt stress, D 13 was often observed to decrease with increase in the stress level (Arndt and Wanek, 2002;Brugnoli and Lauteri, 1991;Celik and Tekeli, 2017;Downton et al, 1985;Ehleringer, 1990;Shaheen and Hood-Nowotny, 2005;Veccelli and de Siqueira, 2017). This is an indication that leaf photosynthesis becomes less discriminating to carbon isotope under stress.…”