Permeation of soil fumigants through agricultural plastic films |
| |
Authors: | M Austerweil B Steiner A Gamliel |
| |
Institution: | (1) Laboratory for Research on Pest Management Application, Inst. of Agricultural Engineering, ARO, The Volcani Center, 50250 Bet Dagan, Israel |
| |
Abstract: | Plastic films are used in soil fumigation to control fumigant emission into the atmosphere. In previous studies it was shown
that the plastic films are permeable to fumigant vapors. Virtually impermeable films (VIF) have been developed to reduce such
emission and to increase the efficacy of pest control. A rapid, accurate, sensitive and simple method to measure the permeability
of plastic films to soil fumigants that was developed in the present study is described in this paper. The method uses a static,
closed system in which the tested film is fixed between two cells. The fumigant is sampled by a solid-phase microextraction
method and measured quantitatively by gas chromatography. The method was used to assess the permeability of two plastic films
— a low-density polyethylene film (LDPE) and a VIF — to commercial soil fumigants formulated individually or in mixtures.
All the tested fumigants permeated through the commonly used LDPE film, in the following descending order of permeability:
methyl isothiocyanate (MITC), methyl bromide (MBr), 1,3-dichloropropene (1,3-D; Telone), chloropicrin (CP). The VIF was impermeable
to all the tested fumigants except MITC, the permeation of which was reduced by 40%. The permeation of some fumigants through
LDPE films was influenced by the formulation used. The permeation of CP was increased when it was combined with MBr in Bromopic.
With Telopic, a mixture of 1,3-D and CP, the permeation of 1,3-D through LDPE film was 62% greater than that of Telone, whereas
that of CP was not affected. The permeation rates of both MBr and CP were 25–30% greater when they were formulated as a mixture
in Bromopic than when they were formulated individually. The formulation of fumigants as mixtures of two components did not
affect their permeability through VIF. This study showed that differences in the suitability of plastic films for soil fumigation
can be measured easily in a laboratory. It also showed that the VIP was more effective than LDPE in reducing losses of fumigant
to the atmosphere, thus allowing more efficient use of fumigants to manage soilborne pests. The presented method helps us
to choose the most adequate film for optimizing fumigation efficacy, and reducing costs and environmental risks.
http://www.phytoparasitica.org posting Sept. 17, 2006. |
| |
Keywords: | Soil fumigation soil fumigants permeation methyl bromide metam sodium chloropicrin 1 3-dichloropropene plastic film |
本文献已被 SpringerLink 等数据库收录! |
|