Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-19T22:50:56.961Z Has data issue: false hasContentIssue false

Microbial and Photolytic Dissipation of Imazaquin in Soil

Published online by Cambridge University Press:  12 June 2017

G. W. Basham
Affiliation:
Univ. Arkansas, Altheimer Lab., Rte. 11, Box 83, Fayetteville, AR 72703
T. L. Lavy
Affiliation:
Univ. Arkansas, Altheimer Lab., Rte. 11, Box 83, Fayetteville, AR 72703

Abstract

Microbial degradation of imazaquin {2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinolinecarboxylic acid} was monitored by measuring 14CO2 evolution for 7 months under controlled laboratory conditions. Up to 10% of the 14C chain-labeled imazaquin that was applied to a Crowley silt loam was evolved as 14CO2 in 7 months. Less evolution of 14CO2 occurred on a Sharkey silty clay, a soil with higher clay and organic matter content, than on silt loam soils. The loss of 66 to 100% of the imazaquin applied to a Crowley silt loam incubated for 8 months at 18 C or 35 C, respectively, suggested that metabolic changes in addition to CO2 evolution were occurring. Rapid loss of imazaquin phytotoxicity occurred when soils were held at warm-moist (35 C and −33 kPa) conditions conducive to microbial growth. Imazaquin was more persistent in soils stored under cool, dry (18 C and −100 kPa) conditions. Imazaquin on a soil surface dissipated rapidly when exposed to ultraviolet light or sunlight. Photodecomposition could be a major mode of imazaquin dissipation if this herbicide is allowed to remain on the soil surface.

Type
Soil, Air, and Water
Copyright
Copyright © 1987 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Basham, G. W., Lavy, T. L., Oliver, L. R., and Scott, H. D. 1987. Imazaquin persistence in three Arkansas soils. Weed Sci. 35: 576582.Google Scholar
2. Braverman, M. P., Lavy, T. L., and Barnes, C. L. 1986. The degradation and bioactivity of metolachlor in the soil. Weed Sci. 34: 479484.Google Scholar
3. Brewer, F., Lavy, T. L., and Talbert, R. E. 1982. Effects of flooding on dinitroaniline persistence in soybean (Glycine max) — rice (Oryza sativa) rotations. Weed Sci. 30:531539.CrossRefGoogle Scholar
4. Crosby, D. G. and Tutass, H. O. 1966. Photodecomposition of 2,4-dichlorophenoxyacetic acid. J. Agric. Food Chem. 14:596599.Google Scholar
5. Gilmour, J. T., Clark, M. D., and Sigua, G. C. 1985. Estimating net nitrogen mineralization from carbon dioxide evolution. Soil Sci. Soc. Am. J. 49:13981402.Google Scholar
6. Goetz, A. J., Wehtje, G., Walker, R. H., and Hajek, B. 1986. Soil solution and mobility characterization of imazquin. Weed Sci. 34:788793.Google Scholar
7. Liang, T. T. and Lichtenstein, E. P. 1976. Effects of soil and leaf surfaces on photodecomposition of 14C-azinphosmethyl. J. Agric. Food Chem. 24:12051210.Google Scholar
8. Messersmith, C. C., Burnside, O. C., and Lavy, T. L. 1971. Biological and non-biological dissipation of trifluralin from soil. Weed Sci. 19:285290.Google Scholar
9. Ogram, A. V., Jessup, R. E., Ov, L. T., and Rao, P. S. C. 1985. Effects of sorption on biological degradation rates of 2,4-dichlorophenoxyacetic acid in soils. Appl Environ. Microbiol. 49:582587.CrossRefGoogle ScholarPubMed
10. Roeth, F. W., Lavy, T. L., and Burnside, O. C. 1969. Atrazine degradation in two soil profiles. Weed Sci. 17:202205.Google Scholar