A yield trial with five replicates was carried out with 2 cv. of spring barley, one suceptible and the other resistant to mildew. Both were treated with two specific mildew-controlling fungicides, one (BASF F 2201) applied as a leaf spray, the other (ICI PP 149) as a seed dressing. From the seedling stage onwards, the susceptible cv. was heavily attacked by mildew; a 20% reduction in yield was found compared with the potential yield. F.s.-A.G.G.H. (Abstract retrieved from CAB Abstracts by CABI’s permission)