Background and Purpose: The objectives of this study were to estimate gene effects and heritability for three important quantitative traits (grain yield components) in two wheat crosses (Divana/Srpanjka and Soissons/Žitarka).
Materials and Methods: Eight generations (namely; P1, P2, F1, F2,
Bc1.1. (P1xF1), Bc1.2. (P2xF1), RBc1.1. (F1xP1) and RBc1.2. (F1xP2)) were raised and subjected to generation mean analysis for detecting the nature of gene effects responsible for inheritance of the number of grains, grainweight and single grain weight per spike of the longest culm.
Results: Digenic epistatic model was adequate to explain variation in
generationmeans for single grain weight in Divana/Srpanjka and for grain weight per spike of the longest culm in Soissons/Žitarka crossing combinations. Additive gene effects were more important for grain weight per spike of the longest culm in Soissons/Žitarka cross, while dominance and epistatic gene effects were predominant in controlling inheritance of single grain weight in Divana/Srpanjka cross. For the number of grains in both crosses, single grain weight in Soissons/Žitarka and grain weight per spike in Divana/Srpanjka crossing combinations, digenic epistatic model failed to
explain variation in generation means.
Conclusions: These data suggest that in crosses where digenic epistatic model was adequate with predominant positive influence of additive gene effects accompanied with high narrow-sense heritability, it is possible to expect advance for traits studied in further segregation generations. Crosses where digenic epistatic model were insufficient to explain all variation in generation means along with low heritability imply more complex nature of inheritance and/or influence of the environment on the expression of
these traits
