B. Dyulgerova, D. Dimova, D. Valcheva, D. Vulchev, T. Popova, M. Gocheva
Abstract. Five winter feed barley varieties were tested at the experimental field of the Institute of Agriculture – Karnobat over a six-year period to assess their yield potential and stability. Varieties Bozhin and Iz Bori are new varieties and Vesletc, Izgrev and Aheloj 2 are widely grown feed barley varieties in Bulgaria. Stability parameters were estimated by the model of Lin and Binns (1988) and GGE biplot methodology was used for graphical display of yield data. According to the results, genotype x environment interactions for grain yield was highly significant indicating genetic variability between genotypes by changing enviroment. Average grain yield of varieties in six-year trail ranged from 5.13 t/ha (Vesletc) to 5.78 t/ha (Bozhin). High yield combined with high stability was demonstrated by new varieties Bozhin end Iz Bori.