Application and development prospect of genomic selection breeding in coniferous trees

Genomic selection (GS) is the preferred, non-transgenic strategy in conifer breeding, significantly accelerating genetic gain and overcoming limitations through early selection and the adoption of advanced, adaptive models. Genomic selection (GS) is a breeding method that uses molecular markers and phenotypic characteristics in the population genome to construct an associated genetic model, and then estimates the breeding value and predicts the phenotype of breeding populations with known genotypes but unknown phenotypes to achieve accurate and efficient genetic breeding. As an important part of the global forests, coniferous trees have high ecological and utilization value. However, due to their slow growth, large genome size, complex phenotypes, and weak foundational research, traditional phenotypic selection breeding is long and difficult. GS can complete the early selection of coniferous trees only based on the genotype after establishing the model, which not only saves the breeding time but also improves the genetic gain. It has become an important research direction in conifer breeding. This review first introduces the principle and method of GS, provides an overview of statistical models used in GS, then summarizes the research status of conifer GS. Finally, the factors affecting the implementation of GS for coniferous tree species were pointed out, and puts forward the prospect of the future development of conifer GS. This review provides strategies and ideas for further research on conifer GS breeding technology.