Lodging Resistance in Oat (Avena sativa): Integrating Agronomy, Phenomics, and Genomics-Assisted Breeding

Lodging limits oat yield, forage value, silage quality, and mechanized harvesting, but resistance cannot be explained by plant height alone. This structured narrative review synthesizes literature available through 1 June 2026 using a tiered evidence framework. After duplicate removal, the review included 119 unique references in total. These comprised 12 Level I studies with direct oat evidence, 30 Level II oat-focused studies requiring further validation, and 77 Level III comparative sources. Overall, 42 sources (35.3%) focused on oat or Avena. The strongest direct evidence supports roles for basal-internode geometry and mechanics, cell-wall composition, canopy architecture, planting density, nitrogen management, and genotype-specific responses to plant growth regulators. However, the direction and magnitude of these effects depend strongly on genotype × management × environment interactions. Evidence for root lodging remains limited because root traits are rarely examined together with direct anchorage measurements and soil mechanical properties. Image-based phenotyping also lacks independently validated, multi-environment oat datasets for model development. Genome-wide association studies and multi-omics analyses have identified candidate loci, genes, and pathways, but independent, homoeolog-aware validation is still needed. We recommend standardized reporting of lodging type, field severity, basal-internode mechanics, root–soil conditions, and imaging protocols. We also propose resource-matched deployment and staged priorities, from phenotyping harmonization to multi-environment validation and causal analysis of belowground mechanisms.