Differential growth responses to sodium salts involve different abscisic acid metabolism and transport in Prosopis strombulifera

LLANES A, MASCIARELLI O., ORDOÑEZ R., ISLA MI, LUNA V

BIOLOGIA PLANTARUM

SPRINGER

Lugar: Berlin; Año: 2014 vol. 58 p. 80 - 88

0006-3134

In this work, the response of the halophytic shrub Prosopis strombulifera to -1, -1.9 and -2.6 MPa osmotic solutions generated by NaCl, Na2SO4 and the iso-osmotic combination of them was studied at 6, 12 and 24 hours after reaching such values in the growing media. By analyzing the concentration of abscisic acid (ABA) and related metabolites and transpiration levels, we observed that ABA levels varied depending on type of salt, salt concentration,organ analyzed, and age of plant. ABA level in leaves was much higher than in roots,presumably because of rapid biosynthesis, and transport from roots. Leaves of Na2SO4-treated plants had the highest ABA levels at -2.6 MPa (24 h), associated with sulfate toxicity symptoms. Significant levels of ABA-glucose ester (ABA-GE) were accumulated in both roots and leaves, whereas levels of phaseic acid (PA) and dihydrophaseic acid (DPA) were low. Roots showed high ABA-GE accumulation in all treatments suggesting ABA transport from roots to leaves. The highest levels of free ABA were correlated with ABA-GE glucosidase activity at -2.6 MPa (24 h). In plants treated with Na2SO4, roots and leaves