ASHS 2025 Conference

Gladiolus(-i), Gladiolus ×hybridus (Iridaceae), is a tetraploid, asexually-propagated, herbaceous perennial floricultural crop. Gladiolus is in the top five cut flower crops in the world for use in floral design. Despite their ability to widely intercross with dwarf stature wild type species, gladiolus have not been developed for the potted plant market. The objective of this analysis is to identify potential genetic marker(s) related to dwarfism to direct future breeding efforts towards the gladiolus potted plant market. In this study we examine 2,662 unique gladiolus cultivars and numbered selections using DNA marker-based analysis. Samples were collected from the public (University of Minnesota) and private (Meyer, Otto) sector gladiolus breeding programs in Minnesota and elsewhere in Europe. A total of 194 dwarfs (90cm) genotypes were identified in our analysis. Dwarfs were defined as being less than 90cm in height of the entire plant including inflorescence at first bloom. Population genetic diversity was analyzed using 17,556 single nucleotide polymorphism (SNP) low-density markers using DArTseq technology. After filtering call rates at the 95% level a total of 2,026 SNPs remained, separating genotypes into 177 dwarfs and 2,235 standard individuals. No private alleles were found when comparing dwarfs to standards. When we narrowed the definition of dwarf to those