Relationship Between Corn Yield and Plant Nutrient Content1

Abstract

AbstractThe purpose of this study was to determine the relationship between corn (Zea mays L.) yield and the nutrient content of corn plants at three stages of growth. Experiments were conducted at two locations. For purposes of this research nutrient content refers to total amount of one or more nutrients contained in the corn plant or some part of it. Most previous research has involved relationships between nutrient concentrations (percentages or parts per million) and corn yield rather than between total amount of nutrients in the plant and corn yield.Corn yields were regressed on the N, P, K, Ca, Mg, Mn, B, Cu, and Zn content of corn plants averaging 25 cm in height and 76 cm in height, and of different plant parts at early tassel. Previous research had regressed yields on nutrient concentrations at the same stages of growth. It was found that in terms of R2 values more precise yield predictions could be made from the nutrient content of whole plants at early growth stages than from nutrient concentrations. At early tassel there was little advantage in using nutrient content for predicting yields when compared to nutrient concentration in different plant parts. These results suggest that early in the life of the corn plant, nutrient content may be a better tool for predicting yields and thus diagnosing possible deficiencies than nutrient concentration.Various correlations between cations in different plant parts were also investigated. Negative correlations between certain cations in plant tissue are frequently reported, but they most often involve concentrations in some specific part of the corn plant at early tassel. In this study negative correlations were observed between percent K and percent Mg in whole plants and in different plant parts. A negative correlation between percent Ca and percent K was observed in leaves but not in stalks. A positive correlation between the content of Ca and K was observed in all plant parts and growth stages, but there was no consistent correlation between K and Mg content over all growth stages and plant parts.