Pesquisa Agropecuária Brasileira
Print version ISSN 0100-204X
ANDREA, Mara Mercedes de et al. Influence of repeated applications of glyphosate on its persistence and soil bioactivity. Pesq. agropec. bras. [online]. 2003, vol.38, n.11, pp. 1329-1335. ISSN 0100-204X. http://dx.doi.org/10.1590/S0100-204X2003001100012.
Pesticide degradation studies are essential to evaluate its impact in the environment and on non-target organisms. The effect of repeated soil applications of the herbicide glyphosate on its dissipation and on soil microorganisms was studied by radiometric and microbial techniques. Results indicated fast dissipation of the [14C]-glyphosate or [14C]metabolites extractable residues (half-life of 0.92±0.29 month), but increasing half-lives of total mineralization ranging from 2.2 to 3.4 months as the number of applications increased from 1 to 4. No significant correlation was found between 14CO2 production and dehydrogenase activity.
Keywords : pesticide residues; mineralization; dehydrogenases; soil treatment.