Beyond the Edit: Integrating CRISPR-Cas Genome Editing Into the Cereal Breeding Pipeline.

Cereal breeding must deliver complex trait combinations under a changing climate, and CRISPR-Cas editing is presented as the technology that will accelerate this. Existing reviews document the editing toolkit thoroughly, yet few follow an edited allele through the steps separating an edited plant from a released cultivar. This review addresses that gap by treating genome editing as one module within a cereal breeding pipeline and asking, at each interface, whether integration has been demonstrated or only proposed. Evidence was selected against three criteria, namely, that the work was performed in a cereal, that the outcome was measured rather than projected and that genotype and environment were stated. Applying this standard across wheat, rice, maize and barley yields a more qualified picture than current summaries suggest. Multiplex editing is the dominant strategy for polygenic traits, yet recovery of a complete multilocus genotype is limited by the least efficient guide rather than the average efficiency. Doubled haploid production shortens fixation only where several loci segregate independently, and its induction, identification and doubling steps impose losses that offset part of the saving. Marker-assisted selection acts on backcross progeny and on haploid inducers rather than among near-isogenic edited events, and genomic selection combined with editing rests on livestock simulations whose assumptions cereals do not meet. Transformation efficiency, licensing of regeneration technology and jurisdiction-specific approval remain binding constraints. Every module has been demonstrated in some cereal. The full sequence has not and closing that gap needs integration studies rather than further gains in editing precision.