Effect of Soil Properties on the Degradation of Isoxaflutole and the Sorption-Desorption of Isoxaflutole and Its Diketonitrile Degradate

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• 作者：Pamela J. Rice ; William C. Koskinen ; and Maria Jose Carrizosa
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2004
• 出版时间：December 15, 2004
• 年：2004
• 卷：52
• 期：25
• 页码：7621 - 7627
• 全文大小：235K
• 年卷期：v.52,no.25(December 15, 2004)
• ISSN：1520-5118

文摘

The transformation of isoxaflutole (ISOX) to its herbicidally active diketonitrile degradate (DKN) wassignificantly enhanced in the presence of soil and occurred more rapidly in systems containing soilwith a greater soil pH. Sorption-desorption of ISOX and DKN in five soils collected within a fieldrevealed both ISOX and DKN were more readily sorbed to soils with greater organic matter, claycontent, and lower soil pH. Sorption of ISOX residues occurred within 2 h, and extracts containedsimilar concentrations of ISOX and DKN at 24 h, suggesting the 24-h sorption coefficients for ISOX-treated systems were actually for mixed ISOX residues. Freundlich sorption coefficients were 3 and4 times greater for ISOX than for DKN. On the basis of the Freundlich organic carbon sorptionconstants, ISOX and DKN can be categorized in the very high and high mobility classes, suggestingtheir potential to leach in the soils needs to be evaluated.Keywords: Isoxaflutole; diketonitrile degradate; sorption; desorption