Abstract
Employing cereal genetic variation in breeding programmes for organic farming is one of the ways to create varieties with higher stability and adaptability. The aim of the study was to compare and evaluate grain yield, quality and other traits of barley pure lines, hybrid populations, variety mixtures, as well as winter wheat hybrid populations and parental varieties, in organic and conventional farming systems. Significant evidence for advantages of using barley mixtures and populations under organic and conventional management systems was not observed. More advantages with respect to yield, adaptability to unfavourable environments and TGW were observed for breeding lines selected for suitability to organic conditions. Combination of distinctive genotypes may result in a fairly stable mixture with average yield above the components. The study confirmed that resistance of winter wheat genotypes to abiotic stress is one of the significant traits that is closely connected with limitation of the wheat productivity in both growing conditions. Yield and grain quality value of winter wheat genotypes was lower under organic conditions compared to a conventional growing system. Advantages of populations were not observed under organic conditions, but significantly higher yield, in comparison to parental varieties, was obtained for two populations in conventional conditions. In general, the yield of populations was intermediate to that of the parents.