Abstract:Dry matter partitioning, root characteristics, chlorophyll content, free proline content and root activity were investigated in potted seedlings of winter wheat (Triticum aestivum L.) cultivars (Zhoumai18 and Yumai49) with Hoagland solution and Hoagland adding 100, 250, 350, and 450 mmol/L NaCl, respectively. The results showed that leaf area, aboveground dry weight and root length in both cultivars significantly decreased in a salinity concentration-dependent manner. In contrast, root characteristics parameters (ie. dry weight, diameter, surface area, volume), root activity and chlorophyll content expressed a trace with a peak at 250mmol/L NaCl; Chla / Chlb ratio were positively correlated with soil salinity. Proline content was higher and fluctuated much more in Zhoumai18 than in Yumai49, and 350 mmol/L NaCl increased the proline content by 1.5 times vs control. The threshold of salinity tolerance was somewhere between 250 and 350 mmol/L in winter wheat under study.