Effects of the low dose of Pb~(2+) on the response of isozymes of POD of winter wheat seedlings roots to Cd~(2+) stress

【Objective】 The effects of the low dose of Pb2+( 300.0 mg/kg) on the response of POD isoenzyme of winter wheat seedlings roots to Cd2+ stress were analyzed to provide theoretical basis for environmental contamination.【Method】 The pot was used to culture winter wheat seedlings under stresses of Cd2+ and Pb2+/Cd2+,and the Polyacrylanid Gel Electrophoresis(PAGE) was used to analyze the expression of POD isoenzyme.【Result】 The expression content of POD isozymes of roots was inhibited by Cd2+ contamination.The inhibition of Cd2+ on the expression content of POD isozymes was the most powerful in the third week after winter wheat seedlings emerged and the influence weakened with the extension of wheat growth stage.The inhibition of 20.0 mg/kg Cd2+ on the expression content of POD isoenzymes was significant in the third and seventh week after winter wheat seedlings emerged.Low dose of Pb2+ aggravated the inhibition of Cd2+ on the expression content of POD isoenzymes of winter wheat roots except for the relief of 120.0 mg/kg Pb2+ to the inhibition of 20.0 mg/kg Cd2+ on it at the third week.【Conclusion】 Cd2+ inhibited significantly the expression content of POD isoenzymes at the first growth stages of winter wheat seedlings and the inhibition weakened with the extension of growth stage.The low dose of Pb2+(300.0 mg/kg) aggravated significantly the inhibition of Cd2+ on the expression of POD isoenzymes of winter wheat roots.