Abstract:A field experiment was performed to investigate responses of crude fibre, soluble sugar, chlorophyll content, stomatal conductance (Gs), intercellular CO2 concentration (Ci), net photosynthetic rate (Pn) and transpiration rate (Tr) of Lolium perenne to trample stress under conditions of waste crumb rubber with different sizes being filled in turf medium. The results showed that under trample stress, Lolium perenne with 1-2 mm crumb rubber in medium had lower crude fibre content than that with 2-4 mm and 4-6 mm, while the control had the highest crude fibre content. Chlorophyll content differed markedly among the treatments, decreased in the order of 1-2 mm＞2-4 mm＞4-6 mm＞control. Soluble sugar content of Lolium perenne was the greatest in the 1-2 mm treatment, followed by 2-4 mm, 4-6 mm treatments and control. The net photosynthetic rate (Pn) and stomatal conductance (Gs) were improved with the addition of crumb rubber, and they all reached the maximum in the 1-2 mm treatment. However, the intercellular CO2 concentration (Ci) decreased substantially. This indicates that turf medium filled with 1-2 mm crumb rubber has higher photosynthetic ability than other treatments. Based on the above analyses, the size of crumb rubber filled in turf medium was found to be correlated with trample resistance of turf. In the present study, turf medium filled with 1-2 mm crumb rubber was higher in trample resistance than that filled with 2-4 mm and 4-6 mm.