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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Distribution and formation of degradation products of C-14-quinclorac in five tropical soils

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Autor(es):
Alonso, Felipe Gimenes [1] ; Mendes, Kassio Ferreira [2] ; Junqueira, Leonardo Vilela [1] ; Takeshita, Vanessa [1] ; Almeida, Cassio De Souza [1] ; Tornisielo, Valdemar Luiz [1]
Número total de Autores: 6
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Ctr Nucl Energy Agr, Ecotoxicol Lab, Ave Centenario 303, BR-13416000 Piracicaba, SP - Brazil
[2] Univ Fed Vicosa, Dept Crop Sci, Vicosa, MG - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: ARCHIVES OF AGRONOMY AND SOIL SCIENCE; v. 66, n. 11 NOV 2019.
Citações Web of Science: 1
Resumo

Quinclorac is an extremely persistent herbicide in the environment. However, information regarding the degradation of this herbicide in the soil is missing. Thus, the objective of this study was to evaluate the behavior of quinclorac in five tropical soils of contrasting textures by quantifying the extracted residue with formation of metabolites, bound residue and mineralization to (CO2)-C-14. The herbicide was applied at the dose of 15.1 Bq per biometric vial. For mineralization, 10 mL of NaOH were used, with weekly analyses of radioactivity in the liquid scintillation spectrometer, up to 240 days after application (DAA). Extractions were performed using NaOH and acetone. Thin Layer Chromatography (TLC) plates were used for the separation of the extracted residue in quinclorac and its metabolites. After the extraction, the soils were burned in a biological oxidizer to quantify the bound residue. Half-life (DT50) ranged from 57.7 to 266.5 days and five metabolites were found. The mineralized (CO2)-C-14 ranged from 12.5 to 25.6%, extracted residue from 104.3% to 23.3% and the bound residue from 3.6 to 49.5%. Quinclorac showed high persistence in the soil, which could cause carryover in subsequent crops and reach non-target organisms, but this depends on the physicochemical characteristics of each soil. (AU)

Processo FAPESP: 17/20497-8 - Relação entre carryover e persistência do quinclorac em solos
Beneficiário:Felipe Gimenes Alonso
Modalidade de apoio: Bolsas no Brasil - Iniciação Científica