'Plant Breeding: Sustaining the Future' Abstracts of the XVIth EUCARPIA Congress, Edinburgh, Scotland, 10-14 September 2001 A CEREAL VARIETY MIXTURE – WHAT’S IN IT? J.S. SWANSTON, A.C. NEWTON Scottish Crop Research Institute, Invergowrie, Dundee

Growing varieties as mixtures has advantages in addition to disease control, namely better and more stable yield and quality.  Molecular markers can overcome varietal component identification and quantification problems, facilitating commercial acceptability.  Pure varieties are far from truly homogenous and selected barley mixtures have malted readily in the laboratory, performing better than their components.  On a commercial scale such advantages would give brewers and malt distillers better raw materials, while reducing inputs, particularly of fungicides.  Currently, there is no breeding of wheat or high enzyme barley specifically for grain distilling.  What qualities are poorly defined and attract no premium, while niche barley development is uneconomical.  However, the useful contributory features of complementary genotypes could be exploited in mixtures, maximising yields in both field and distillery.