Study on Correlation and Causation relations of Morphological traits in synthetic wheat liens

Attention to Genetic diversity of wild relative plants important as a natural germplasm that are huge source of genetic diversity, study on wild relative plants is important. So for study of synthetic wheat lines that received from international center for maize and wheat research (CIMMYT), on 2008-2009 season crops an experiment including 69 synthetic wheat lines with seven controls (Bam, Sistan, Bahar, Roshan, Kavir, Pishtaz and Akbari) by Alpha lattice design include 2 replications which have been done in the research filed seed and plant breeding research institute of Karaj. The twenty morphological and physiological traits were measured. The biological yield trait has the highest correlation (r=0.77**) with grain yield. Biological yield, harvest index, plant height, penultimate and grain width are five traits that entered into the stepwise regression’s model and explain %95.2 of data variation. In continue for study on relative among traits, path analysis has been done. It showed that biological yield and harvesting index consecutively have 0.685 ** and 0.569 ** highest and positive direct effects and plant’s height has the highest and negative (-0.174 **) direct effect.