1. Diagnosis of Nitrogen Deficiency in Maize and the influence of Hybrid and Plant Density

The precise diagnosis of maize N status has proven to be a difficult task because of annual 1 variation in internal N-use efficiency (kg grain kg- N uptake) and temporal change in N concentration in plant tissue. Analysis of leaf N concentration (g N leaf) has not been a consistently successful N diagnostic because of temporal and hybrid differences in specific leaf weight (SLW=g leaf me2 leaf). An alternative N diagnostic; specific leaf nitrogen (g N m-2 leaf), is unrelated to leaf mass. Maximum...