The effect of different temperature on growth of seedling in greenhouse tomato lines was investigated. The results indicated that plant fresh weight, dry weight, height, leaf area, leaf number and truss number of tomato lines were significantly decreased by reduction of air temperature inside greenhouse; significant difference was found between lines; except plant fresh weight and leaf area, co-effect was found in plant dry weight, height, leaf number and truss number between line and temperature treatment; and relations of plant dry weight and RGR against days after germination (t) were simulated with LnDW=a + b×t + c×t2 and RGR=b + 2×c×t (c≠0), respectively Based on above, TOSSIM model concerning tomato seedling growth was established.
