Gene Action in Second, Third and Fourth Generations for Two Durum Wheat Crosses

Five self-fertilized generation means ( , , , and ) of two crosses in durum wheat (Triticum durum Desf.), the first (Azeghar-1 Um-Rabie-5), and the second (Leeds Waha), were genetically analyzed to estimate gene action for the traits: plant height, total chlorophyll percent in flag leaf, heading time, spike length, number of flag leaf venation and flag leaf area. Two models were used for analyzing the components of the generation means, parameters model and five- parameters model. The results showed that the three parameter model was inadequate for the inheritance of all the studied traits in the two crosses. Additive, dominance and epistatic effects for polygenes revealed significant role to express the studied traits.