As crop yields are pushed closer to biophysical limits, achieving yield gains becomes increasingly challenging and will require more insight into deterministic pathways to yields. Here, we propose a wiring diagram as a platform to illustrate the interrelationships of the physiological traits that impact wheat yield potential and to serve as a decision support tool for crop scientists. The wiring diagram is based on the premise that crop yield is a function of photosynthesis (source), the investment of assimilates into reproductive organs (sinks) and the underlying processes that enable expression of both. By illustrating these linkages as coded wires, the wiring diagram can show connections among traits that may not have been apparent, and can inform new research hypotheses and guide crosses designed to accumulate beneficial traits and alleles in breeding. The wiring diagram can also serve to create an ever-richer common point of reference for refining crop models in the future.
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We are indebted to R. Richards, Y. Manes and J. LeGouis for reviewing a first draft of the wiring diagram. We acknowledge the role that the IWYP played in identifying the need for a tool to drive crop research and physiological breeding, and thank the IWYP for financial support to develop the wiring diagram.
The authors declare no competing interests.
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Reynolds, M.P., Slafer, G.A., Foulkes, J.M. et al. A wiring diagram to integrate physiological traits of wheat yield potential. Nat Food 3, 318–324 (2022). https://doi.org/10.1038/s43016-022-00512-z