Our objective in this study was to determine which type of hybrid cultivar in rye (Secale cereale L.) offers optimum chances of combining high yield performance, with satisfactory yield stability. Nine single crosses, 33 three-way crosses, 33 two-component-mixtures of three-way crosses, and 33 double crosses, forming genetically balanced sets of material, were tested. Additionally, 33 top crosses were included in this study which were not genetically balanced with the other material. All entries were grown at two locations in South Germany and one location in North Germany in 1976 and 1977 (Exp. 1); 24 of these entries were tested at two additional sites in North Germany (Exp. 2). The average performance of single and threeway crosses did not differ; the three-way crosses yielded 0.5 q/ha less than the three-way cross mixtures in Exp. 1 and surpassed the double crosses by 0.5 and 1.4 q/ha in Exp. 1 and Exp. 2, respectively. Phenotypic stability generally increased from three-way to top crosses. However, the differences in average stability between hybrid types were small as compared to the remarkable variability within each type. Taking into account performance, stability, and economy of seed production, a double cross or an equivalent form with a two-line synthetic as pollinator parent is probably the most favorable hybrid type for rye at present.
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