Improved corn lines having high protein and/or oil content and a method for producing such a lines. In another embodiment, improved corn lines having high oleic fatty-acid content, and/or either elevated or lowered saturated fat content, and a method for producing such a lines. In yet another embodiment, improved corn lines having a starch composition including starch components having a lower peak onset, having lower or higher enthalpy of gelatinization (cal/g), having lower or higher range of gelatinization (.degree. C.), and/or having lower or higher percentage retrogradation. According to the present invention, new genes are introduced from a novel source, viz. Tripsacum dactyloides L., into the Corn-Belt genome or other conventional corn lines and thus the genetic diversity is increased and germplasm and value-added trait enhancement are allowed through traditional plant breeding practices. Introgression merges Tripsacum genetic material into the corn breeding stock. Selection for lines having desired characteristics from the corn lines as well as having improved protein, oil, and/or starch characteristics provides the improved breeding stock of the present invention. In one embodiment, selection is based on near-infrared reflectance measurement of protein, oil, and/or starch of seed. In another embodiment, selection is based on differential scanning calorimetry measurement of starch thermal characteristics. In yet another embodiment, selection is based on gas chromatographic measurement of fatty-acid oil composition of seed. In some embodiments, particular types of fatty acids are selected for in the breeding process.