Effect of Combined Application of Methyl Isothiocyanate and Chloropicrin on Their Transformation
Wei Zhenga,b,*,
Scott R. Yatesb,
Sharon K. Papiernikc and
Mingxin Guoa,b
a Department of Environmental Sciences, University of California, Riverside, CA 92521
b USDA-ARS, Soil Physics and Pesticides Research Unit, George E. Brown Jr. Salinity Laboratory, Riverside, CA 92507
c USDA-ARS, North Central Soil Conservation Research Laboratory, Morris, MN 56267
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Fig. 1. Mass spectra (electron impact, EI) of hydrolysis products of methyl isothiocyanate (MITC): (a) methyl isocyanate and (b) 1,3-dimethylthiourea.
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Fig. 2. Chemical reactions associated with products of MITC hydrolysis in basic solution.
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Fig. 3. Influence of binary-fumigant application on degradation rates in Arlington sandy loam at three initial concentrations. The dashed line represents the degradation of methyl isothiocyanate (MITC) and the solid line is chloropicrin.
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Fig. 4. Effect of fumigant sequential application on the dissipation of (a) chloropicrin and (b) methyl isothiocyanate in soil. Chloropicrin was applied 14 d followed by metam sodium, and then incubated for 1 and 5 d at 25 ± 0.5°C.
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Fig. 5. Effect of fumigant sequential application on the dissipation of (a) methyl isothiocyanate (MITC) and (b) chloropicrin in soil. Metam sodium was applied 3 d followed by chloropicrin, and then incubated for 5 and 10 d at 25 ± 0.5°C.
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Copyright © 2004 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.
