ISHS Acta Horticulturae 255: III International Symposium on Soil Desinfestation
DISTRIBUTION AND DISSIPATION OF 1,3-DICHLOROPROPENE AFTER INJECTION IN STRUCTURED LOAMY SOILS |
| Authors: | J.H. Smelt, M. Leistra, S.J.H. Crum, W. Teunissen |
| Abstract:
In some areas in the Netherlands with heavier loamy soils an increasing interest is noted in fumigating this soils with 1,3-dichloropropene. However, little information is available about its effect in these soils. To get more information, the concentration patterns of (Z) and (E) 1,3-dichloropropene in loamy soils (25–31 % clay) were measured three times on four fields after injection of dichloropropene (170 kg/ha) with a Combiject shear injector with subsoil sprayers. The doses for the layers, defined as the value for the concentration-time integral in the water phase of the soil, were estimated with a computer model. In most trials the spread of the fumigant was slow and nonuniform. The cloddy structure, the rather high moisture contents and the comparatively high transformation rates resulted in concave concentration- and dose patterns. So bad mortalities may be expected near the soil surface and in the lower part of the cultivated layer. Additional treatments of the top layer are necessary to obtain high mortalities in the whole cultivated layer. The non-uniform distribution is also highly unfavourable for fumigant efficacy. In one trial the soil was also covered with plastic sheeting. This resulted in higher contents near the soil surface, but the total dissipation rate of the fumigant was only slightly slower. In two trials, after a short initial period (3–8 d) the amount of the fumigant decreased unexpectedly rapid, which was caused by an accelerated transformation. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
