Dairy manure incorporation stimulates rapid atrazine mineralization in an agricultural soil

Abstract

profondeur. t-'utru,n.'.-qre. IL-nii-1g-laCl atrazine,6tait rapidement et compldtement convertie en CO-r, en passant,par I'hydroxatrazine, par les bouillies activees. La phase cle decalage pr6t6dant la disparition de l'atrazine etait significativement plus courte dans le sol provenant des parcelles trait6es au fumier. Desiuitures microbiennes stables repiquees a intervalles hebdomadaires continuaient de min6raliser I'atrazine, ce qui confirme que les micro-organismes m6tabolisant I'atrazine sont responsables de la degradation de I'herbicide dans le sol utilise.

Characterization of an Atrazine-DegradingPseudaminobactersp. Isolated from Canadian and French Agricultural Soils

“…However, the ability to utilize the herbicide as a carbon source should be a significant selective advantage in atrazine- treated soil. Our results and the results of other recent studies indicate that atrazine-mineralizing bacteria are now widespread in soils that are subjected to conventional agricultural management practices and that the activity and abundance of these organisms may be enhanced by repeated application of the herbicide or by simple soil management practices, such as manure application (3,50,53,64). Several of our isolates, all of which contained atzABC, completely mineralized atrazine and converted ring 14 C to 14 CO 2 .…”

“…The bacteria described in this paper were isolated from soils obtained from four farms. Two of the soils were obtained from sites in Canada; one of these soils, the site 1 soil (64), was a loam soil (pH 5.9, 3.0% organic matter) obtained from a site located near Ottawa, Ontario, and the other, the site 2 soil, was a loam soil (pH 6.0, 1.4% organic matter) obtained from a site located near Ste.-Hyacinthe, Québec. Two calcareous soils, the site 3 soil (30) (pH 8.4, 1.6% organic matter) and the site 4 soil (3) (pH 8.2, 1.9% organic matter), were obtained from sites located on the outskirts of Paris, France.…”

“…[ring-U- 14 C]atrazine (specific activity, 4.5 mCi/mmol; radioactive purity, 95%) was purchased from Sigma Chemical Co. (St. Louis, Mo.). Parent compounds and transformation products were analyzed by reverse-phase HPLC by using a C 18 column and an instrument equipped with a UV detector (set at 220 nm) coupled in series with a radioactivity detector (64). The solvent used was 70% methanol-30% 5 mM Na 2 HPO 4 (pH 9.0) (solvent system 1) or 50% methanol-50% 10 mM ammonium acetate (solvent system 2).…”

“…More recently, however, there have been several reports of rapid atrazine mineralization in agricultural soils (3,27,64,66), and a variety of atrazine-mineralizing bacteria, including members of the genera Pseudomonas, Rhizobium, Acinetobacter, and Agrobacterium, have been isolated from soils that have come in contact with this chemical (2,7,43,44,54,58,70). These bacteria commonly initiate atrazine degradation by a hydrolytic dechlorination reaction.…”

Biostimulation for the Enhanced Degradation of Herbicides in Soil

“…It is noteworthy that the degree of enhancement of atrazine degradation was even greater, in that it was completely degraded in P-supplemented extract within 40 hours, compared to less than 10% degradation without the P supplement. Sewage sludge and corn meal Alachlor and trifluralin Significant dissipation of herbicide achieved in amended treatments [41] Maize straw Methabenzthiazuron Significantly enhanced the degradation and mineralization of the herbicide [42] Dairy manure Atrazine Identified as a successful technique to enhance the remediation of herbicide-contaminated soil [43] Dairy manure Atrazine Lag period prior to herbicide degradation was significantly shortened in manure-treated plot [44] Cornmeal, rye grass, and poultry litter Cyanazine and fluometuron…”