Evolution of salt tolerance in Arabidopsis thaliana on siliceous soils does not confer tolerance to saline calcareous soils

Abstract Purpose Alkaline salinity constrains crop yield. Previously, we observed local adaptation of Arabidopsis thaliana to saline-siliceous soils (pH ≤ 7) and non-saline carbonate soils. However, no natural population A. was localized on saline-alkaline This suggests that tolerance evolved may not confer alkaline salinity. hypothesis explored by addressing physiological molecular responses differ in either non-alkaline or carbonate. Methods native (high salinity, HS), alkalinity, HA), with intermediate levels these factors (medium saline-alkalinity, MSA) were cultivated common gardens saline-calcareous substrates. Hydroponics irrigation experiments confirmed the phenotypes. The growth, mineral concentrations, proline content, osmotic potential, genetic variation distribution, expression selected genes involved alkalinity assessed. Results HS performed best soil hydroponics 5.9). more sensitive conditions than HA MSA. fitness under ranked according MSA > HS. Under maintained ion homeostasis, balance, higher key saline ( AHA1 , root HKT1 FRO2 shoot NHX1 IRT1 ). Conclusion In does provide Plants (MSA) have plasticity adapt those locally adapted individual stress factors.