Response of spring cereal crops to soil residues of ethofumesate*

Abstract

Summary:For evaluation of soil residues of ethofumseate [(±)2‐ethoxy‐2,3‐dihydro‐3,3‐dimethylbenzofuran‐5‐yl‐methylsulphonate], spring barley (Hordeum vulgare L.) and spring wheat (Triticum aestivum L.) were sown in soil planted 11 months previously with sugar‐beet (Beta vulgaris L.) and previously treated with band or broad‐cast applications of the herbicide at rates of 1.68‐4.48 kg/ha. The height of barley and wheat was suppressed only where ethofumesate was applied broadcast and the soil was not ploughed after sugar‐beet harvest. Three months after sowing, the 4.48 kg/ha rate suppressed the height of barley 18% and wheat 34%. In another experiment, barley grew normally on soil treated the previous year with pre‐planting and post‐emergence applications of ethofumesate where ploughing followed sugar‐beet harvest. For all treatments, yields of straw and grain were not significantly lower than those of the untreated check plots. The dissipation of ethofumesate 24 weeks after application to sugar‐beet was 89–100% when applied on a band compared to 85‐95% when applied broadcast.