Evaluation of genetic diversity of two-row barley by tissue culture potential

This study examined tissue culture responses and genetic variability among 25 two-row barley genotypes preserved in the Osman Tosun Gene Bank, including both Türkiye landraces and foreign- origin genotypes, with the objective of optimizing genetic resources for barley breeding programs. Key tissue culture parameters – callus induction rate, cal- lus weight, regeneration capacity, and culture effi- ciency—were evaluated to access how diversity of genotypes influences tissue culture outcomes. Results revealed significant variation across all traits. Genotypes 77 and 1972 achieved the highest callus induction rates (100%), while genotype Zeynelağa exhibited the lowest (57.5%). Genotype 417 showed superior regeneration capacity (81.9%), and culture efficiency was highest in genotypes Standard Cultivar 138 (90.0%) and 1972 (70.0%). Principal Component Analysis (PCA) indicated that the first two principal components accounted for 87.84% of the variance in tissue culture responses, providing valuable insights into genotype relationships and trait performance. Hierarchical clustering analysis revealed four distinct groups, with Cluster 1 displaying the highest mean performance across traits. Collectively, these find- ings underscore the role of diversity of genotypes in enhancing tissue culture efficiency and plant regen- eration. High-performing genotypes, including 77, 1972, 417, and standard cultivar 138, show consid- erable promise for biotechnological applications and future barley crop improvement initiatives.