Abstract:Mung Bean (Phaseolus aureus) seedlings treated with trehalose were frozen and freezedried. Mg2+, K+-ATPase activities from the purified protoplasmic membranes and the tetrazolium (TTC) reduction from the freeze-dried seedlings were investigated, The freeze-dried seedlings treated with trehalose showed higher enzyme activities than those of the control. As the concentration of trehalose increased, Mg2+, K+-ATPase activities and the TTC reduction were increased too. At 30 ℃, the Mg2+, K+-ATPase activities in frozen seedlings were about twice higher than those of the control. The results indicated that trehalose is a good protectant for the frozen or freeze-dried plant materials.