Effect of Sewage Irrigation on Biological Characteristics of Wheat

In this pot experiment,different concentrations of sewage from Linfen city was used to irrigate two wheat varieties growing in dry land or water land,and the effects of different sewage irrigation treatments on the early-stage growth and some physiological indexes of wheat seedlings were studied.The results indicated that wheat seedlings irrigated by low concentration of sewage had a higher value in plant height,root length,root number,fresh weight and dry weight than the control samples;on the contrary,wheat seedlings treated with high concentration of sewage had a lower value in above indexes than the control.As the concentration of sewage increased,the MDA content in wheat leaves increased,but the SOD activity decreased gradually.The POD activity of Jinmai No.79 in dry land decreased when the sewage concentration increased.The POD activity of Linyou No.2069 in water land increased first and then decreased when the concentration of sewage increased,namely these two wheat varieties showed different resistances to sewage.The wheat samples irrigated by low concentration of sewage contained more free proline in their leaves,but the free proline content rapidly decreased with the increase in sewage concentration. Two wheat varieties in treatment 1 and treatment 2 showed certain advantages in each index. Therefore,the proper ratio of fresh water to sewage used to irrigate wheat in Linfen city should be between 1:1 and 1:2.