Transport of Imazethapyr in Undisturbed Soil Columns

O'Dell, Joey; Wolt, Jeff; Jardine, Philip M.

doi:10.2136/sssaj1992.03615995005600060008x

Cited by 29 publications

(25 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The results of imazaquin desorption in water from PC are presented in Table 3 After 2 and 24 h the percent desorbed increased from 10% for 4.32 mmol kg −1 to 21% for 17.3 mmol kg −1 imazaquin sorbed. After 7 d desorption increased to 15.3% for 4.32 mmol kg −1 and to 24.6% for 17.3 mmol kg −1 These results demonstrate that some amount of imazaquin is more strongly bound to PC and desorbed more slowly as was found for imazethapyr (O'Dell et al, 1992; Johnson et al, 2000). As a whole, imazaquin is less tightly bound to PC than the previously studied anionic herbicide sulfometuron, which under similar conditions desorbed only 3% (Polubesova et al, 2000).…”

Section: Resultssupporting

confidence: 52%

“…Imazaquin desorption was determined in water and in electrolyte solutions. Desorption kinetics for another imidazolinone herbicide (imazethapyr) from soil was found to be much slower than adsorption (O'Dell et al, 1992; Johnson et al, 2000). It was supposed that there is some amount of herbicide that is extremely tightly or nearly irreversibly bound (Johnson et al, 2000).…”

Section: Methodsmentioning

confidence: 97%

See 1 more Smart Citation

Imazaquin Adsorbed on Pillared Clay and Crystal Violet–Montmorillonite Complexes for Reduced Leaching in Soil

et al. 2002

View full text Add to dashboard Cite

Ground water pollution due to herbicide leaching has become a serious environmental problem. Imazaquin [2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)quinoline-3-carboxylic acid] is an herbicide used to control broadleaf weeds in legume crops. Imazaquin is negatively charged at the basic pH of calcareous soils and exhibits high leaching potential in soils. Our aim was to design formulation of imazaquin to reduce herbicide leaching. Imazaquin sorption on pillared clay (PC) and crystal violet (CV)-montmorillonite complexes was studied. The CV-montmorillonite complexes become positively charged with adsorption of CV above the cation exchange capacity (CEC) of montmorillonite, and thus can sorb imazaquin. The Langmuir equation provides a good fit to isotherms of imazaquin sorption on PC and CV-montmorillonite complexes, but for charged complexes an equation that combines electrostatics with specific binding was preferred. Maximal imazaquin sorption was 17.3 mmol kg-1 for PC and 22.2 mmol kg-1 for CV-montmorillonite complexes. The extents of imazaquin desorption into water were 21% for PC and 5% for CV-clay complexes. The presence of anions decreased imazaquin sorption on both sorbents in the sequence phosphate > acetate > sulfate. Reduction of imazaquin sorption by the anions and the extent of its desorption in electrolyte solutions were higher for PC than for CV-clay complexes. Leaching of imazaquin from CV-montmorillonite formulations through soil (Rhodoxeralf) columns was two times less than from PC formulations and four times less than that of technical imazaquin. The CV-montmorillonite complexes at a loading above the CEC appear to be suitable for preparation of organo-clay-imazaquin formulations that may reduce herbicide leaching significantly.

show abstract

Section: Resultssupporting

confidence: 52%

Section: Methodsmentioning

confidence: 97%

Imazaquin Adsorbed on Pillared Clay and Crystal Violet–Montmorillonite Complexes for Reduced Leaching in Soil

et al. 2002

View full text Add to dashboard Cite

show abstract

“…Estudos indicam que o imazethapyr, em solos não-revolvidos, move-se na coluna do solo até 30 cm (O'Dell et al, 1992). O imazethapyr é adsorvido em maior quantidade em pH baixo (Che et al, 1992;Gennari et al, 1998), tornando-se menos móvel e mais persistente no solo (Loux & Reese, 1993).…”

Section: Resultsunclassified

Persistência dos herbicidas imazethapyr e clomazone em lâmina de água do arroz irrigado

Santos¹,

Marchesan

Machado

et al. 2008

Planta daninha

View full text Add to dashboard Cite

RESUMO -Os herbicidas podem persistir no solo ou ser carreados para fora da área, contaminando mananciais hídricos a jusante da lavoura. Em vista disso, o presente trabalho objetivou estimar a persistência dos herbicidas imazethapyr e clomazone na lâmina de água de arroz irrigado. Para isso, foi realizado um ensaio com diferentes doses e épocas de aplicação da mistura formulada (75 g i.a. ha -1 de imazethapyr + 25 g i.a. ha -1 de imazapic) e clomazone (1.500 g i.a. ha -1 ). Para determinação dos produtos na água de irrigação, foram coletadas amostras de água a partir do primeiro dia até 62 dias após a inundação. Os resultados demonstraram que o período de detecção dos herbicidas na água de irrigação foi mais longo para o imazethapyr que para o clomazone. A meia-vida do imazethapyr na lâmina da água variou conforme o tratamento, com valores entre 1,6 e 6,2 dias, e a do clomazone foi de cinco dias.Palavras-chave: imazethapyr, clomazone, residual na água, Oryza sativa.ABSTRACT -Herbicides can persist in soil and be transported from the application site to the environment. An experiment was conducted to estimate imazethapyr and clomazone persistence in rice paddy water. The treatments included application of the formulated herbicide mixture (imazethapyr 75 g a.i. L -1 + imazapic 25 g a.i. L -1 ) and clomazone (500 g a.i. L -1 ). Imazethapyr and clomazone concentrations in water were evaluated from the 1 st to the 62 nd day after flooding. The period of herbicide detection in water was longer for imazethapyr. Imazethapyr half-life in paddy water varied between 1.6 and 6.2 days and clomazone half-life was 5 days.

show abstract

“…It can be inferred that sorption of imazaquin continued after 24 h of incubation and resulted in less imazaquin desorbing from the 72‐ and 168‐h incubation treatments than the 24‐h incubation treatment. O'Dell et al (1992) and Johnson et al (2000) showed similar time dependence to imazethapyr sorption.…”

Section: Resultsmentioning

confidence: 73%

“…It may be most appropriate to think of herbicide sorption as a multiphasic reaction. Research demonstrates that sorption is composed of a rapid, almost instantaneous phase, followed by a more gradual phase (Hamaker et al, 1966; Letey and Oddson, 1972; Chien and Clayton, 1980; Boesten and van der Pas, 1988; Ball and Roberts, 1991b; Kookana et al, 1992; O'Dell et al, 1992; Dang et al, 1994; Chardon and Blaauw, 1997; Johnson et al, 2000). The rapid phase is most likely the result of sorption on surface sites of organic matter, clay colloids, and soil organic matter colloid complexes (Ball and Roberts, 1991b).…”

mentioning

confidence: 99%

Incubation Time Effects on Imazaquin Desorption as Determined by Nonequilibrium Thin‐Soil Disc Flow

et al. 2004

View full text Add to dashboard Cite

Because organic sorption in soil may never reach equilibrium, a thin-disc flow nonequilibrium method may be helpful in understanding herbicide-soil interactions. This research was conducted to (i) determine the influence of incubation time on imazaquin [2-(4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl)-3-quinolinecarboxylic acid] desorption from soil, (ii) examine the influence of solution flow velocities on desorption, and (iii) elucidate the most appropriate kinetic model to describe imazaquin leaching. Soil at 7.5% moisture w/w was treated with imazaquin and incubated for 24, 72, and 168 h. Treated soil was sealed in an in-line filter apparatus and rinsed with 5.0 mM CaCl2 at 0.33, 0.67, or 1.0 mL min(-1). Effluent was collected as 1.0-mL fractions for a total of 50 mL. Flow was stopped for 24 h. When flow resumed, fractions were collected for an additional 15 mL. After the initial desorption, 79% of the imazaquin incubated for 24 h was leached. Increasing incubation time beyond 24 h reduced imazaquin leaching. After both desorption events, 13% of the initially applied imazaquin remained in the soil incubated for 168 h, compared with 7% with soil incubated for 24 h. Elovich and Freundlich kinetics accounted for 98% of the variance observed in the imazaquin desorption curves. First-order and diffusion kinetics accounted for 91% of the variance. Incubating soil for 72 h before desorption reduced the rate of imazaquin desorption by approximately 12%, compared with the 24-h incubation treatment. Imazaquin desorption was not affected by wash solution flow rate. These data suggest that the kinetics of desorption in prolonged desorption events are limited by transport phenomena (i.e., particle and film diffusion).

show abstract

Transport of Imazethapyr in Undisturbed Soil Columns

Cited by 29 publications

References 0 publications

Imazaquin Adsorbed on Pillared Clay and Crystal Violet–Montmorillonite Complexes for Reduced Leaching in Soil

Imazaquin Adsorbed on Pillared Clay and Crystal Violet–Montmorillonite Complexes for Reduced Leaching in Soil

Persistência dos herbicidas imazethapyr e clomazone em lâmina de água do arroz irrigado

Incubation Time Effects on Imazaquin Desorption as Determined by Nonequilibrium Thin‐Soil Disc Flow

Contact Info

Product

Resources

About