The study looked at how salt stress affects the growth of Melilotoides ruthenica seedlings. They found that as the salt concentration increased, the levels of soluble proteins and sugars in the seedlings decreased, while the proline content increased. The seedlings exposed to high salt concentrations showed lower protein and sugar levels. The photosynthetic rate and other parameters of the seedlings varied with the salt concentration and exposure time. Seedlings under low salt concentrations had higher photosynthetic rates, while those under high salt concentrations had lower rates. Stomatal limitation and water use efficiency increased with higher salt concentrations.