Plant regrowth in response to defoliation relies on efficient nitrogen use. Roche et al. find that remobilisation of water soluble carbohydrate stores in leaves of perennial ryegrass (Lolium perenne) is coordinated with nitrogen availability to support efficient N assimilation into amino acids in leaf and sheath tissues.
Spatiotemporal changes in cytokinin content in response to changes in the internal carbon-nitrogen balance indicate that cytokinins could act as a mobile signal between below- and above- ground tissues in response to defoliation.
Roche, J., Turnbull, M. H., Guo, Q., Novák, O., Späth, J., Gieseg, S. P., … Love, J. (2017). Coordinated nitrogen and carbon remobilization for nitrate assimilation in leaf, sheath and root and associated cytokinin signals during early regrowth of Lolium perenne. Annals of Botany, 119(8), 1353–1364. https://doi.org/10.1093/aob/mcx014