| This paper studied the growth of two kind of marine economy microalgae(Dunaliella salina and Platymonas subcordiformis) under the effects of butachlor andacetamiprid as well as the capability of the two kind of marine microalgae inaccumulating and degradating butachlor and acetamiprid.The results show that the growth of Dunaliella salina was stimulated under lowconcentration of butachlor culture medium and the growth of Platymonassubcordiformis was also stimulated under low concentration of acetamiprid culturemedium, significantly inhibited under high concentration of butachlor and acetamipridculture medium. Platymonas subcordiformis and Dunaliella salina were mainlyshow inhibition within the concentration of butachlor and acetamiprid. The96h-ECso of butachlor to Dunaliella salina and Platymonas subcordiformis wereseparately 0.047mg/L and 7.574mg/L. The 96h-EC50 of acetamiprid to Dunaliellasalina and Platymonas subcordiformis were separately 108.151mg/L and13.348mg/L.The two kind of pesticides also affected photosynthetic pigment and proteincontent of Dunaliella salina and Platymonas subcordiformis. The absolute contentof photosynthetic pigment and protein had the similar trend like the growth of thealgae.Dunaliella salina was stimulated the activities of superoxide (SOD) andperoxidase (POD) under low concentration of butachlor and acetamiprid, inhibitedthe activities of SOD and POD under high concentration Of butachlor and acetamipridculture medium. Under the the stress of two kind of pesticides, the activity of SODof Platymonas subcordiformis fluctuated larger near the control group, the activity ofPOD of Platymonas subcordiformis exihibited decreasing in the other day andbeginned recovering in the after day, Platymonas subcordiformis had a strongself-regulation and self-recovery capability.Platymonas subcordiformis had the capability of degradating butachlor. At theconcentration of 3mg/L and 6mg/L, the degration ratio of 5 days was 97.4% and 78.1％, average degradation rate per day 0.568mg/L and 0.937mg/L, respectively.Degradation kinetics of butachlor in the algae solution can be fitted well with thefirst-order kinetic equation. Futhermore, Platymonas subcordiformis also exhibitedsignificant capability of bioaccumulation. Under the concentration of 3 mg/L and6mg/L the maxium bioaccumulation was 1.739 mg/gDW and 1.927mg/gDW, themaxium BCF was 1.922×103 and 1.048×103, respectively. The two kind ofmircoalgae had no significant capability of degradating acetamiprid, however, hadsome capability of bioaccumulation. At the concentration of 50mg/L and 100mg/L,the degration ratio of Dunaliella salina of 5 days was 3.0％and 0.4％, averagedegradation rate per day 0.296mg/L and 0.086mg/L, respectively; the maxiumbioaccumulation was 10.918 mg/gDW and 19.520mg/gDW, the maxium BCF was0.222×103 and 0.197×103, respectively. At the concentration of 10mg/L and20mg/L, the degradation ratio of Platymonas subcordiformis of 5 days was 20.3％and11.7％, average degration rate per day 0.406mg/L and 0.467mg/L, respectively; themaxium bioaccumlation was 1.690mg/gDW和2.996 mg/gDW, the maxium BCF was0.199×103 and 0.170×103, respectively. Degradation kinetics of acetamiprid in thetwo kind of microalgae solution can be fitted with the first-order or the second-orderkinetic equation.This study offers basic data for toxicity appraisement, risk appraisement ofpesticide and the further study of toxicity mechanisms of pesticide. The resultsrevealed the biodegradation of butachlor and acetamiprid by algae was importantpathway of the degradation of the chemical in aquatic environment.
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