Genetic Diversity for Grain Yield and its Components in Winter Wheat Genotypes (Triticum aestivum L.)

In order to detect the most effective characters on grain yield and its component in winter wheat genotypes, an experiment in a randomized complete block design with three replications was conducted at Research Station of the Islamic Azad University, Tabriz Branch. Planting seed, application of fertilizers and fertilizers and pesticides and irrigation regimes were processed as they are usually done in the region. Some traits such as days to heading, days to maturity, height plant, main spike weight, straw yield, grain number per spike, grain weight per spike, grain yield and harvest index were characterized. Analysis of variance revealed that there were significant differences among genotypes for most of the traits except the weight of main spike and grain number per plant. Results also showed that the highest phenotypic (19.77%) diversity belonged to the weight of main spike and least to days to maturity and days to heading (with 0.27% and 0.52% ) respectively. Results of factor analysis showed that four factors accounted for 82.73% of the total variation. Cluster analysis, based on traits under study, grouped the genotypes into two groups. The first group consisted of seven and the second on of five genotypes.