Spectral high-throughput assessments of phenotypic differences in biomass and nitrogen partitioning during grain filling of wheat under high yielding Western European conditions

► Source sink relationships of six high yielding wheat cultivars were predicted by spectral vegetation indices. ► Spectral vegetation indices were during grain filling better related to yield related plant traits than directly to final grain yield. ► Relative dry matter contents of spikes and grains were best related to spectral reflectance information. ► Nitrogen uptake by the spikes could be tracked by spectral reflectance measurements until kernel dough development.