Reports of improvement in sweet corn (Zea mays saccharata) for grain yield and agronomic traits through introgression of genes from the field corn (Zea mays L.) are common in literature. However, few studies have reported improvement in field corn varieties for organoleptic and/or nutritional properties through the transfer of recessive alleles that condition sweetness in sweet corn into the field corn. Field and laboratory studies were conducted to determine changes in quantitative and qualitative characteristics of three F₁ hybrids derived by crossing sweet corn (pollen parent) unto field corn and their F₂ populations derived by sibmating approximately 200 ears from each of the F₁ hybrids. Our results showed significant changes in grain yield, grain protein concentration, carbohydrate and calcium contents in the F₁ hybrids and F₂ populations. One hybrid (Pop31DMR x Sweet corn) had 21% grain yield advantage over the maternal parent while another hybrid (Obatanpa x Sweet corn) showed superiority for grain protein (27.3%) with corresponding lower carbohydrate content. Grains obtained from the F₂populations had lower seed protein content than their respective maternal parents or the F₁ hybrids and with corresponding higher carbohydrate content. Percent (%) loss in grain protein in the F₂ seeds was higher than for other nutrient elements. Modest heterotic response was recorded for grain yield in Pop31DMR x Sweet corn cross and for grain protein concentration in Obatanpa x Sweet corn cross. 

Key words: Grain yield, nutritional properties, inbreeding depression, heterotic response.