Effect of La(NO_3)_3 on the Physiological Indices of Cold Tolerance in Livistona chinensis Seedlings

The effect of La(NO3)3 on the physiological indices of cold tolerance in Livistona chinensis seedlings was conducted,The L.chinensis seedlings were sprayed with 0,100,200,300,400,500,600 mg/L La(NO3)3 solution,the contents of malondialdehyde(MDA),soluble sugar,chlorophyll and chlorophyll a/b ratio of L.chinensis seedlings were determined under 20,5,12 and 10 ℃ for 24 h,respectively,The results of the MDA contents with La(NO3)3 treatments were lower than those of the control,and changed slowly under temperature stress,and the contents of soluble sugar,chlorophyll and chlorophyll a/b ratio increased compared with the control.It was concluded that La(NO3)3 agents could boost the physiological indices of cold tolerance in L.chinensis.And the appropriate concentration which significantly affected the physiological indices of cold tolerance was 300 mg/L.