Effects Of Heavy Metal Pollution Of Cd And Zn In Soil On Growth And Quality Of Potato

Effects of heavy metal Cd and Zn in soil on growth,physiological and biochemical indexes,quality of potato in red soil and K,Ca,Mg,Fe,Cu,Zn in potato tubers were studied in a pot experiment.The main results were as follows:1.Under single Cd or Zn pollution,with increasing in Cd or Zn contents in the soils,the single plant yield of potato tuber decreased,plants became dwarfish,the contents of chlorophyll decreased,SOD activities decreased,and the contents of MDA increased.These results meant that Cd or Zn produced toxicity to potato.The toxicity of Cd to the under ground part of potato plants was more serious than that to the overground part,and,contrarily,the toxicity of Zn to the overground part of potato plants was more serious than that to the the under ground part.2.In this pot experiment,the contents of vitamin C in potato tubers decreased, soluble sugar and reducing sugar increased,with increasing in concentrations of soil Cd.The contents of starch in potato tubers decreased when the concentrations of soil Cd lower than 5 mg/kg,while increased when the concentrations of soil Cd higher than 5 mg/kg,and the starch contents corresponded to the highest soil Cd concentrations were lower than those in the control.The contents of starch,protein, soluble sugar and reducing sugar increased with increasing in concentrations of soil Zn.The contents of vitamin C increased when the concentrations of soil Zn lower than 40 mg/kg,while decreased when the concentrations of soil Zn higher than 40 mg/kg,and the vitamin C contents corresponded to the highest soil Zn concentrations were lower than those in the control.Effects of soil Cd on the different indexes of potato tubers were more obvious than those of soil Zn.3.Contents of K,Ca,Mg,Fe,Cu,and Zn in the tubers of two kinds of potato plants were affected by different concentrations of Cd or Zn.In this experiment,the contents of Fe and Cu decreased with increasing in concentrations of Cd in soils.The contents of Ca decreased when the concentrations of soil Cd lower than 5 mg/kg, while increased when the concentrations of soil Cd higher than 5 mg/kg,and the Ca contents corresponded to the highest soil Cd concentrations were lower than those in the control.K contents decreased,while Mg and Zn contents increased with increasing in concentrations of soil Cd.The contents of K in tubers of Zhongshusanhao decreased,the contents of Mg increased and the contents of Zn decreased when the concentrations of soil Cd lower than 5 mg/kg.The contents of K increased when the concentrations of soil Cd higher than 5 mg/kg,and the K contents corresponded to the highest soil Cd concentrations were lower than those in the control.The contents of Mg decreased,but the contents of Zn increased,and the contents of Mg or Zn corresponded to the highest soil Cd concentrations were lower than those in the control.The contents of Ca,Mg,Fe,Cu,and Zn in potato tubers increased with increasing in concentrations of soil Zn.The contents of K in tubers of Zhongshusanhao increased when the concentrations of Zn lower than 40 mg/kg,while decreased when the concentrations of Zn higher than 40 mg/kg.The contents of K in tubers of Daxiyang increased when the concentrations of Zn lower than 80 mg/kg, while decreased when the concentrations of Zn higher than 80 mg/kg.In this experiment,there were differences in absorption of K,Ca,Mg,Fe,Cu,and Zn in the tubers between two kinds of potato plants.