Yield Performance and Genotype × Environment Interaction of Elite Rye Germplasm Selected from a Greek Landrace Under Mediterranean Conditions

Rye landraces (Secale cereale L.) are an important source of genetic diversity and continue to offer valuable opportunities for the development of productive and well-adapted cultivars. Despite their breeding potential, relatively little is known about the field performance and yield stability of elite genotypes selected from heterogeneous landraces under Mediterranean growing conditions. In this study, fifteen elite rye half-sib families selected under nil-competition from the traditional Greek landrace “Vevi” were evaluated together with the original population and the commercial cultivar ‘Dukato’ across three contrasting Mediterranean environments. The objectives were to assess their agronomic performance, investigate genotype × environment interaction, and identify promising germplasm combining high yield with broad adaptation using AMMI and GGE biplot analyses, complemented by sixteen parametric and non-parametric stability indices. Grain yield, seed protein content, plant height, and days to ear emergence were recorded. Broad-sense heritability was consistently high (H2 = 0.95–0.99), whereas environmental conditions explained most of the observed phenotypic variation. Grain yield showed a positive association with plant height (r = 0.651, p < 0.01) and a negative association with days to ear emergence (r = –0.703, p < 0.01). Among the evaluated genetic materials, G9 and G11 combined high productivity with stable performance across environments, while G6 produced the highest grain yield but was better suited to favourable environments. The close agreement among the different stability analyses increased confidence in family ranking and selection. Overall, the results highlight the considerable breeding value of the traditional Greek rye landrace “Vevi” and demonstrate that combining multi-environment testing with complementary stability analyses provides an effective framework for identifying elite rye genotypes with high yield potential and broad adaptation to Mediterranean environments.