Gene action for grain yield and its correlation with yield components in a diallel cross of winter wheat (Triticum aestivum L.)

Magnitude and type of gene actions in a specific population are the main criteria for the parents' selection that will develop the best recombinants after hybridization. Information about the genetic control of complex traits is useful for the further development of efficient breeding programs. In order to identify action of genes for grain yield plant-1 and its correlation with main yield components, incomplete diallel crossing was applied. The field trial was conducted at the experimental field of the Agricultural Advisory Service in southeastern Europe, during season 2012-2013. Mean values of F1 generation showed that crosses Apache × Prima had the highest value of grain yield plant-1 and Jackson × Balkan had the lowest. Common type of inheritance for grain yield plant-1 was over dominance. The ANOVA revealed that this trait was controlled by additive and non-additive effects. The best general combiner for grain yield plant-1 was Apache, and two crosses (Dragana × Jackson; Balaton × Nevesinjka) showed significant SCA effects. Components of genetic variance showed that dominant was more important than additive component, and the total number of dominant genes were in excess over the number of recessive genes in all parents. Furthermore, moderately low value of narrow sense heritability (h2=31.96%) was observed for grain yield plant-1 . Parent Sana contained maximum dominant genes, whereas parent Jackson had maximum recessive genes. Grain yield plant-1 was significantly correlated with tillers numbers plant-1 at genotypic level (rg=0.494). The results from this study might be helpful for creating new wheat cultivars with highyielding potential.