Yao, J., Ma, H., Zhang, P., Ren, L., Yang, X., Yao, G., Zhang, P. and Zhou, M. 2011. Inheritance of stem strength and its correlations with culm morphological traits in wheat (Triticum æestivumL.). Can. J. Plant Sci. 91: 1065-1070. The genetic effect of stem strength and its correlation with culm morphological traits were investigated in a 7×7 diallel cross of wheat involving seven parents (Ningmai 8, Ningmai 9, Yangmai 5, Yangmai 9, Yangmai 11, Sumai 3, and Wangshuibai) during the crop season of 2009-2010. Significant differences were observed among genotypes for stem strength. The estimates of general combining ability (GCA) pointed out that the best general combiners for stem strength were Ningmai 8 and Yangmai 9. The additive-dominance model was adequate for stem strength, and it was controlled by the over dominance type of gene action. Ningmai 8, followed by Yangmai 5, possessed maximum recessive genes, whereas Wangshuibai had maximum dominant genes. Stem strength could be controlled by three genes with low narrow sense heritability. A statistical analysis showed that stem strength is highly significantly correlated with nine culm morphological traits except for diameter of the first basal internode.