Table 4.
Correlation coefficients (r) between crude protein (CP) and amino acids in corn, wheat, and barley (as-is basis)^1,2

Item	Correlation coefficient (r)
	CP	Lys	Met	Cys	Thr
Corn
CP	-	0.322	0.288	0.267	0.393
Lys		-	0.369	0.475	0.548
Met			-	0.681	0.332
Cys				-	0.389
Thr					-
Wheat
CP	-	0.277	0.397	0.362	0.505
Lys		-	0.349	0.518	0.576
Met			-	0.677	0.352
Cys				-	0.332
Thr					-
Barley
CP	-	0.542	0.559	0.476	0.741
Lys		-	0.660	0.819	0.902
Met			-	0.832	0.744
Cys				-	0.801
Thr					-

All data have shown significant difference (P<0.001).
The number of observations of corn, wheat, and barley are 325, 56, and 58, respectively.