Potencial de lixiviação de imazapic e isoxaflutole em colunas de solo

In view of the intense use of herbicides, this work aimed to evaluate the leaching potential of imazapic and isoxaflutole in soil columns, using samples of two Haplorthox soils (LVd sandy loam texture and LRd clay texture), originated from Iguaracu (PR). Thus, assays were carried out aiming to determine the amount of water necessary to promote herbicide movement in the columns. On the second phase of the work, using only LVd samples, the assays consisted of applications of imazapic (0, 65 and 130 g ha-1) and isoxaflutole (0, 35 and 70 g ha-1) on the top of the columns, followed by application of 40 mm of water. Three days after herbicide application, each column was divided into sections of 0-5, 5-10, 10-15, 15-20 and 20-25 cm and bioassays with Brachiaria decumbens and Cucumis sativus were installed to evaluate herbicide leaching. Results from the first phase indicate that irrigation depths > 40 mm promoted herbicide leaching in the LVd samples and of > 60 mm in the LRd samples, for isoxaflutole. The results of the second phase (40 mm of water in the LVd samples) indicate that, depending on the dose and bioindicator applied, imazapic leaching occurred up to the depth of 10-15 cm or of 15-20 cm. Even at the highest rates applied, isoxaflutole downwards movement in columns was restricted to a soil depth of 5-10 cm.

[1]  J. T. Neto,et al.  Persistência de isoxaflutole em solo argiloso cultivado com Batata , 2005 .

[2]  M. H. Inoue,et al.  Efeito residual de isoxaflutole após diferentes períodos de seca , 2005 .

[3]  H. E. Garrett,et al.  Determination of isoxaflutole (balance) and its metabolites in water using solid phase extraction followed by high-performance liquid chromatography with ultraviolet or mass spectrometry. , 2002, Journal of agricultural and food chemistry.

[4]  C. A. Tormena,et al.  Calagem e o potencial de lixiviação de imazaquin em colunas de solo , 2002 .

[5]  P. Alves,et al.  Influência do resíduo de colheita de cana-de-açúcar sem queima sobre a eficiência dos herbicidas imazapic e imazapic + pendimethalin , 2001 .

[6]  I. F. Yada,et al.  Retenção pela palhada, de herbicidas aplicados em pré- emergência na cultura do milho, em plantio direto , 2000 .

[7]  L. R. F. Alleoni,et al.  Influência do pH na sorção de imazaquin em um Latossolo Vermelho Acriférrico , 2000 .

[8]  H. A. Ruiz,et al.  Lixiviação de glyphosate e imazapyr em solos com diferentes texturas e composição química: I - método do bioensaio , 2000 .

[9]  B. Xing,et al.  Sorption of isoxaflutole by five different soils varying in physical and chemical properties , 1999 .

[10]  F. A. Ferreira,et al.  Lixiviação do glyphosate e do imazapyr em solos com diferentes texturas e composição química: II. método analítico , 1999 .

[11]  D. Mulla,et al.  Spatial variability of imazethapyr sorption in soil , 1999, Weed Science.

[12]  M. Rezende,et al.  Comportamento dos herbicidas atrazina e alaclor aplicados em solo preparado para o cultivo de cana-de-açucar , 1999 .

[13]  J. M. Reichert,et al.  Retention of imazaquin in soil , 1997 .

[14]  J. Weber,et al.  A Review of Field Lysimeter Studies to Describe the Environmental Fate of Pesticides , 1996, Weed Technology.

[15]  S. Vizantinopoulos,et al.  Persistence and leaching of the herbicide imazapyr in soil , 1994, Bulletin of environmental contamination and toxicology.

[16]  M. Arienzo,et al.  Evaluation of the mobility of C14-labelled pesticides in soils by thin layer chromatography using a linear analyser , 1994 .

[17]  D. Shaner,et al.  The Imidazolinone Herbicides , 1991 .

[18]  M. Loux,et al.  Adsorption of Imazaquin and Imazethapyr on Soils, Sediments, and Selected Adsorbents , 1989, Weed Science.

[19]  Jack T. Trevors,et al.  Glyphosate in the environment , 1988, Water, Air, and Soil Pollution.

[20]  B. Hajek,et al.  Sorption and Mobility of Sulfometuron and Imazapyr in Five Alabama Soils , 1987, Weed Science.

[21]  G. Ogner.  Glyphosate application in forest—ecological aspects , 1987 .

[22]  C. Helling.  Pesticide Mobility in Soils III. Influence of Soil Properties1 , 1971 .