Relationships between Important Agronomic and Phonological Traits in Inbred Lines from the Crosses Roshan × Sabalan in Bread Wheat

In order to assess the relationship of grain yield and some of the agronomic traits recombinant inbred lines (RIL) population of bread wheat derived from the Roshan × Sabalan were used to detect the informative traits on grain yield as the suitable criteria for indirect selection and path coefficient analysis. Two hundred and sixty seven recombinant inbred lines with three control cultivars (Roshan, Sabalan (as parents) and Mahdavi) were evaluated in Augmented design. This experiment was conducted at Shahid Bahonar University of Kerman on growing season of 91-92 Different inbred lines showed significant transgressive segregation for grain yield and its components. Grain yield had significant correlation with all the components. Four traits were entered in the stepwise of regression model containing: total spikes weight, number of fertile trills, main spike weight and number of grain per plant which totally justified 63.7 percent of grain yield variation. The first trait that entered in this model was total spikes weight, it was justified the highest variation of the yield. Due to the result of path analysis, total spikes weight had the most direct effect on grain yield (0.336) and the most indirect effect on number of grain per plant through total spikes weight on grain yield (0.293). Among four traits entered in regression model, the most important trait for improving of seed yield was total spikes weight. Regarding to the high correlation of total spike weight with grain yield, its high direct effect and correlation response for grain yield (1.35), it can be introduced the most effective trait for grain yield improvement.