Partitioning of Biomass Versus Nitrogen to Leaf, Stem and Ear Components during Corn Development.

Improvement in corn productivity as well as resource efficiency depends, in part, on acquiring new knowledge concerning physiological pathways and timeframes with respect to plant nitrogen (N) allocation and efficiencies. Hence, this present study examined the coinciding partitioning of biomass and N in plant components at several corn growth stages. The experiment evaluated five hybrids varying in apparent nitrogen use efficiency (NUE) at two N rates (0 and 112 Kg N/ha) at two locations in Indiana. The mean results of biomass and N partitioning over time, as well as the remobilization of N from stem and leaf sources during the grain filling period, will be discussed in this presentation. We were especially interested in understanding the N remobilization process among leaf, stem and ear shoots versus new whole-plant N uptake from flowering to late grain fill under low to moderate soil mineral N conditions. The key factors that influenced final NUE and its components nitrogen internal efficiency (NIE) and nitrogen recovery efficiency (NRE) will also be presented.