Inorganic nitrogen is a key element for plant growth under salt stress.
A comparative study including phys-iological responses, ion content, transcript regulation of ammonium/nitrate transporters (AMTs/NRTs) aswell as key enzymes for nitrogen assimilation was undertaken in wild salt-tolerant tomatoes (Solanumpennellii) and cultivated tomatoes (Solanum lycopersicon) exposed to 100 mM NaCl for 1 and 7 days.
Incomparison to S. lycopersicon, S. pennellii was more salt tolerant as evidenced by its higher survival rate,lower biomass reduction, and less salt injury (reduced electrolyte leakage and proline accumulation).
In root tissues of both species, salt exposure (7 days) reduced the mRNA expression levels of low affin-ity nitrate transporters (NRT1.1 and NRT1.2). This was associated with a decline in both nitrate contentand expression level of the nitrate reductase gene (NR).