Genetic diversity of wheat (Triticum aestivum L.) genotypes based on cluster and principal component analyses for breeding strategies

Determination of genetic diversity is useful for plant breeding and hence production of more efficient plant species under different conditions. Accordingly, the most common wheat (Triticum aestivum L.) genotypes including 36 winter wheat genotypes cultivated in different regions of Iran were selected, grown and analyzed for genetic diversity. The experiment was conducted at the Agricultural Research Farm of Shahed University, Tehran, Iran as a randomized complete block design with three replications. All traits, except emergence time and heading time were statistically significant among different genotypes. Cluster analysis based on squared Euclidean distance and ward's method, categorized the cultivars into seven groups. The highest genetic distance was observed between Sardari and Spn/Mcd/Cama/3/Nzr/4/Passarinho (SP) genotypes. Based on Principal Component Analysis (PCA), the first five components explained over 97% of genetic variation. Cluster analysis based on PCA using the first five principal components indicated six separate groups of genotypes, with the maximum genetic distance observed between Sardari and Vorona/Kauz (VO) genotypes. Such differences in genetic component of traits studied in this manuscript can be applied as a new source of variation in other breeding programs and crossing nurseries for wheat improvement.