Correlations were determined between the crude protein (CP) and lysine or methionine concentrations of grain from wheat (cultivar: palmiet), barley (cultivar: clipper) and triticale (cultivar: usgen 19) grown in the Western Cape region of South Africa. Twenty samples of varying CP content were collected for each grain type from different areas within the winter-rainfall sub-region. The relationships between CP content (x; percentage on an air-dry basis) and lysine concentration (y; percentage of CP) were as follows: (wheat) y = 6.380 – 0.198 x, (r2 = 0.85); (barley) y = 6.003 – 0.167 x, (r2 0.92); (triticale) y = 5.538 – 0.156 x, (r2 = 0.75). The relationships between CP content (x; percentage on an air-dry basis) and methionine concentration (y; percentage of CP) were as follows: (wheat) y = 2.115 – 0.025x, (r2= 0.39); (barley) y = 1.527 – 0.030x, (r2= 0.59); (triticale) y = 1.581 – 0.022x, (r2 = 0.31). It was concluded that the regression equations may be used as a rapid screening method for predicting the lysine and methionine content of South African wheat, barley and triticale grain from CP content.
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