ASHS 2024 Conference

Spinach (Spinacia oleracea L.) is a highly nutritious leafy green known for its abundance of health-promoting components. Plant height (tallness), particularly relevant for efficient machine harvesting, is a critical trait of interest in spinach cultivation. This study aimed to conduct a genome-wide association study (GWAS) to identify single nucleotide polymorphism (SNP) markers associated with tallness in spinach and to perform genomic prediction for this trait. GWAS was conducted on a panel of 307 USDA spinach germplasm accessions, utilizing 15,058 SNPs derived from whole-genome resequencing. Various statistical models, including GLM, MLM, FarmCPU, and BLINK, were employed in the analysis using the GAPIT 3 tool. Significant quantitative trait loci (QTL) were identified on chromosome 2, along with two QTL on chromosome 6. Specifically, the SNP marker SOVchr4_38323167 at 38,323,167 bp on chromosome 4, and two SNPs, SSOVchr6_8139833 and SOVchr6_91175684 at 8,139,833 bp and 91,175,684 bp respectively on chromosome 6, exhibited robust associations with tallness. Genomic prediction demonstrated high accuracy, with a prediction ability (GA) represented by an r value of 0.71 in the panel. The identified SNP markers and genomic prediction metrics provide valuable tools for breeders to select spinach plants and lines with desired tallness traits through marker-assisted selection (MAS) and genomic selection (GS), thereby enhancing spinach breeding efforts.