Abstract: Using the warm-season turfgrass ‘Zhongping No.1’ buffalograss as experimental material，effects of low temperature stress on osmotic regulation substances and root vitality were studied. The results showed that osmotic regulation substances closely related to the cold acclimation adjustment mechanism of buffalograss seedlings under low temperature stress. With the prolonged of the treatment，contents of soluble sugar and protein as well as praline increased. But the content of soluble sugar increased gently at the later stage; the content of soluble protein did markedly at all time. This displayed soluble protein maybe played an important role in adjustment mechanism under low temperature. Then change of proline content was sensitive to cold stress. And proline content sharply increased in the earlier stage and slowly decreased again with the extension of stress time. However，the content of proline remained at a relatively high level throughout the course of cold stress.Meanwhile root vitality of buffalograss seedlings was affected largely by low temperature. The root vitality decreased quickly under low temperature stress. This demonstrated the root system was important to maintain normal growth and development of plants， and it maybe was looked upon as an important indicator for identification of cold tolerance of plants.

Key words: low temperature stress; buffalograss; osmotic regulation substance; root vitality