Effect of Terramycin on Activity and Communities of Soil Microbe

Wheat rhizospere soil was collected and added different amount of terramycin,making the concentration be 0,30,50,70 mg.kg-1.The effect of different concentration of terramycin on the soil microbes(including bacteria and actinomycetes) was investigated,using colony-counting methods,in order to assess its influence upon the microbial number in rhizosphere soil.The results showed that the number of soil microbes were greatly changed.The number of bacteria reduced as the concentration increasing.It had more significant effect on the concentration of 10 mg·kg-1,30 mg·kg-1 and increased a little in the concentration of 50 mg·kg-1,then continuously reduced.The number of actinomycetes was increased as the concentration increasing.In the effect of the different concentration of terramycin,the activities of alkaline phosphatase reduced obviously,it did slightly influence to the desaturase while nearly did no influence on urinary enzyme.The activities of alkaline phosphatase was much higher than that of acid phosphatase in alkali soils.But along with the time raise,the enzyme activities of each kind recovered gradually.