Effect of organic amendments on the bioremediation of cyanazine and fluometuron in soil
Abstract Biostimulation may offer a viable approach to remediate soils containing high concentrations of herbicides. We determined the effects of cornmeal, ryegrass and poultry litter on the degradation of cyanazine and fluometuron (250 μmol kg‐1) in a Dundee silt loam. All three amendments enhanced cyanazine degradation with half lives of 18.2 d in ryegrass‐, and 21 d in cornmeal‐ or poultry litter‐amended soil, compared to 28.3 d in unamended soil. The amendments differentially affected patterns of metabolite accumulation. After 42 d, 45% of the 14C was recovered as dechlorinated (hydroxy cyanazine) metabolites in ryegrass‐amended soil compared to <16% in other treatments. Significantly less 14C was extracted from cornmeal‐amended soil than the other treatments, suggesting a relationship between cyanazine dissipation and incorporation into unextractable bound residues. Ryegrass had the greatest stimulatory effect on fiuometuron degradation. Half lives for fiuometuron were 41.0, 57.3, 27.7, and 66.4 d fo...