Overcoming breeding barriers with genome editing in autopolyploid crops

Autopolyploid crops play a central role in global agriculture, yet their complex genomes pose significant barriers to genetic improvement. High allelic diversity, extensive redundancy, and polysomic inheritance impede both conventional breeding and the implementation of modern biotechnological tools. Genome editing offers a powerful alternative by enabling precise, multi-allelic modification of traits associated with yield, quality, and stress resilience. However, progress across autopolyploid crops remains uneven due to low transformation and regeneration efficiencies, limited genomic resources, and challenges in achieving complete allele disruption. This review focuses on recent advances in genome editing across four economically important autopolyploid crops-potato (Solanum tuberosum), alfalfa (Medicago sativa), sugarcane (Saccharum spp.), and blueberry (Vaccinium corymbosum). We highlight the diversity of traits targeted through CRISPR/Cas systems, including reporter and selectable marker validation, tuber and forage quality, biomass composition, stress tolerance, flowering modulation, and plant regeneration. We also describe technical constraints affecting genome editing in autopolyploids including genotype-dependent recalcitrance, low transformation and editing efficiency, multiallelic targeting and chimerism, outlining emerging solutions such as multiplexed designs, endogenous promoters, morphogenic regulators and virus-based approaches, among others. Together, these developments provide a path toward efficient and heritable genome editing in complex polyploid genomes, setting the stage for next-generation precision breeding in crops vital to food, forage, and bioenergy security.