Determination of chlorimuron and metsulfuron residues in two soils of Argentina using a rapid seed-bioassay.
The presence of chlorimuron ethyl and metsulfuron methyl in two soils was determined by a modified petri dish bioassay. Pregerminated seeds of maize and sunflower were placed in petri dishes containing 85 to 100 g of treated soil. Radicle root lengths were measured after 24 h. Chlorimuron had no effect on maize on the Balcarce soil, however 0.007 microg g(-1) decreased sunflower root length. Chlorimuron decreased maize and sunflower root length regardless application dose on the San Cayetano soil. Metsulfuron decreased maize root length at 0.04 microg g(-1) and sunflower at 0.021 microg g(-1) on the Balcarce soil. On the San Cayetano soil metsulfuron at 0.001 microg g(-1) decreased maize and sunflower root length. The phytotoxicity of chlorimuron and metsulfuron changed according to soil type and dose. Maize and sunflower were 1.3-1.5 and 1.3-1.8 times respectively more sensitive to chlorimuron on the San Cayetano soil than on the Balcarce soil. In the case of metsulfuron, maize was similarly sensitive on both soils but sunflower was 1.7-2.0 times more sensitive on the San Cayetano soil than on the Balcarce soil. Phytotoxicity increased as organic matter (OM) content decreased and/or when the soil pH and concentration increased.
Castro
M C
MC
Departamento de Producción Vegetal, Suelos e Ingeniería Rural, Facultad de Ciencias Agrarias, Universidad Nacional de Mar del Plata, C.C. 276, 7620 Balcarce, Argentina.
Bedmar
F
F
Monterubbianesi
M G
MG
Peretti
A
A
Barassi
C A
CA
D001118:Argentina; D001190:Arylsulfonates / Q000009:adverse effects / Q000032:analysis*; D001681:Biological Assay / Q000379:methods; D006368:Helianthus / Q000254:growth & development; D010573:Pesticide Residues / Q000009:adverse effects / Q000032:analysis*; D011743:Pyrimidines / Q000009:adverse effects / Q000032:analysis*; D012639:Seeds / Q000254:growth & development; D012989:Soil Pollutants / Q000009:adverse effects / Q000032:analysis*; D013453:Sulfonylurea Compounds / Q000009:adverse effects / Q000032:analysis*; D003313:Zea mays / Q000254:growth & development
D001190:Arylsulfonates; D010573:Pesticide Residues; D011743:Pyrimidines; D012989:Soil Pollutants; D013453:Sulfonylurea Compounds; C050296:metsulfuron methyl; C112343:chlorimuron ethyl