Sorption of penconazole applied as a commercial water–oil emulsion in soils devoted to vineyards

A non‐destructive method for testing two components of the behaviour of soil‐applied agricultural chemicals over a long period

“…Triadimenol and propiconazole are used either in foliar, seed or soil treatments, and penconazole in foliar treatments, especially in vineyards. However, as a result of spraying, dripping, wind and rain, this latter lipophilic compound can enter the soil and accumulate on various constituents 39–41. These three triazoles have low PSA and HBD values (Table 2) consistent with efficient diffusion through the membrane 14, 42.…”

“…4) was unexpected under the present experimental conditions. It is well known that it is adsorbed on OM and clay minerals40, 47 and therefore on vermiculite, which exhibits a clay structure 48. Owing to its accumulation on various soil constituents, penconazole is also considered to be a pollutant 39–41.…”

“…It is well known that it is adsorbed on OM and clay minerals40, 47 and therefore on vermiculite, which exhibits a clay structure 48. Owing to its accumulation on various soil constituents, penconazole is also considered to be a pollutant 39–41. Taking into account its log D value, which is close to that of several soil‐applied phytochemicals, and its binding properties, long‐time studies of the spatial behaviour of this lipophilic fungicide need special attention.…”

Influence of commercial formulation on the sorption and leaching behaviour of propyzamide in soil

“…Földényi et al (2013) reported that adsorption of chlorosulfuron on sandy soil decreased markedly in the presence of the forming agent Supragil. However, some studies show an opposite behaviour where sorption in batch systems is greater from the formulated product than from pure active substance (Beigel et al, 1998;Pose-Juan et al, 2010a;2010b); it has been postulated that coformulants may enhance the sorption of active substance due either to a layering effect or to enhanced penetration of pesticide onto the less polar sites of soil organic matter (Pose-Juan et al, 2010b). Cox and Walker (1999) provided a rare example where sorption of a 50% wettable powder formulation of linuron was compared with that of technical material based on soil incubation at field capacity and centrifugation to extract pore water at intervals up to 28 days.…”

Influence of commercial formulation on leaching of four pesticides through soil

“…A few recent studies have investigated formulation types other than controlledrelease, undertaking batch experiments that compare sorption of pesticides in soil slurry systems when added as pure substances or as commercial formulations (e.g. Beigel & Barriuso, 2000;Pose-Juan et al, 2010;Földényi et al, 2013). We have shown that such experiments will not always capture formulation effects and proposed that a centrifugation methodology provides a better measure of any influence of formulation under natural soil conditions (Khan & Brown, this issue).…”