ABSTRACT
Preliminary compositional nutrient diagnosis (CND) norms for maize (Zea mays L.) were developed from a small database as means and standard deviations of row-centered log ratios V X of five nutrients [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg)] and a filling value R, which comprised all nutrients not chemically analyzed and quantified in 72 leaves of hybrid ‘Pioneer 3044.’ Norms were derived from maize grain yields higher than 7.7 t ha−1. Principal-component analysis performed using CND nutrient indexes allowed us to identify an antagonism between N and Mg explained by the calcareous nature of the soil and the relevant N fertilization with ammonium (NH4 +), and a positive interaction between P and K, and P-Ca and K-Ca antagonisms. Maize plants tended to take up lower amounts of N and K and higher amount of Mg in our calcareous soil than the concentrations of these nutrients reported to be optimum.
ACKNOWLEDGEMENTS
The authors thank FAZ-UJED for its laboratory service. Field work was partially supported by the Universidad Autónoma de Nuevo León, Facultad de Agronomía, when the second author was in his doctoral program. We are thankful to anonymous reviewers for their input, which helped us to improve the paper. This research is dedicated to the memory of Mr. Emilio Olivares, who was a great gentleman and a visionary grower of corn; data for the present study were collected from a maize field on his property.