Screening And Studying On The Funguses For Degrading The Ethametsulfuron-methyl

The residues of ethametsulfuron-methyl in soil have been reported to cause damage to succeedding rice and other crops . there is a need to develop a method for the detoxification of ethametsulfuron -methyl in soil and elimination of its harmful effect on crops.In the present study, we screened two funguses named F1and F2 from the soil polluted by ethametsulfuron-methyl. the two funguses have a power ability to accelerating the degradation of ethametsulfuron-methyl The main results were summarized as follows:1. to detecting the residue concentration of ethametsulfuron-methyl in soil, we chose the method of bioassay. We screened the rice species named xiangzaoxian-24 as the detecting crops , and its height is fit to evaluating the concentration of such chemical , In the concentration of 0 to 80μg/L, the toxicity regression qutation is Y=3. 6483+1. 3811X, the relational coeffient(r) is 0. 997558(0. 05), detecting limit is 1.12μg/L.2. from the soil polluted by ethametsulfuron-methyl , we separated two funguses, which adapt to growth in the surrounding contain such chemical There is no side effect to these funguses in the concentration of lOOOmg/L, To test the ability of those funguses , wo add ethametsulfuron-methyl to the culture medium for F1, F2, the concentration was 20mg/L, after cultured 144h, the residuel concentration of this chemical in Fl culture medium was 8mg/L, in F2 was 9. 47mg/L, the degradation rate was 60% and 52. 7%, then , in the natural condition the chemical halflife is 55d(pH 5.5).3. Changing the pH value of solution of ethametsulfuron-methyl to 7.8, 5.7, 4.1, 3.0, 2.0 , keep these solution in the same condition, after 5d, 15d, 30d, 45d, 60d, to detect the residual concentration of the chemical in slution, we found the lower of the pH value , the faster of the degradation , after 60d the residual concentration were9. 8mg/L,4. 3mg/L, 3. 2 mg/L, 3 mg/L, 2. 4 mg/L, from the datum, we drawed the standard curve of the degradation in differ pH condition, from the curve ,we predicted...