Graphical Analysis for Grain Yield of Wheat and its Components Using Diallel Crosses

Half diallel crosses of nine Iranian wheat cultivars were used for graphical analysis and estimation of genetic parameters related to yield and its components. Parents with F2 generations were evaluated in a randomized complete blocks design with three replications. The analysis of variance revealed significant differences among genotypes for all traits except tiller number and grain weight per main spike. The test of Jinks and Hayman revealed that assumptions are valid for flag leaf length, plant height, grain yield per plant, main spike length and peduncle length, but for flag leaf width and peduncle weigth when one parent was excluded, the assumptions were fulfiled. According to the estimations of average degree of dominance and results of graphical analysis, the gene actions for flag leaf length, flag leaf width, plant height, grain yield per plant, main spike length, peduncle length and peduncle weight were partial dominance