A 2-year split-plot field experiment investigated the influence of selected sulfonylurea herbicides including chlorsulfuron mixtures and presowing seed treatment using triadimenol/imazalil/fuberidazole (Baytan Universal 19·5 WP) on the incidence of naturally occurring net blotch (Drechslera teres (Sacc.)) Shoem of barley. All the herbicides examined provided effective and season-long weed control at a similar level that no significant differences in weed density and weed dry weight were found amongst herbicide treatments. Significant (P<0·05) increases in disease prevalence over the weedy check were recorded in herbicide treated plots throughout the evaluation period, but disease severity remained unaffected. Presowing seed treatment with Baytan Universal provided significant control of net blotch of barley compared with the control throughout the evaluation period. No phytotoxicity was observed in any of the treatments.