Genetic diversity survey of Mentha aquatica L. and Mentha suaveolens Ehrh., mint crop ancestors

• Published in: Genetic resources and crop evolution 2019-04, Vol.66 (4), p.825-845
• Main Authors: Vining, Kelly J., Pandelova, Iovanna, Hummer, Kim, Bassil, Nahla, Contreras, Ryan, Neill, Kristin, Chen, Hsuan, Parrish, Amber N., Lange, Bernd Markus
• Format: Article
• Language: English
• Subjects: Agriculture; Biomedical and Life Sciences; Breeding; Carvone; Chemical composition; Collection; Essential oils; Genetic diversity; Genomes; Genotypes; Genotyping; Germplasm; Life Sciences; Markers; Mentha aquatica; Mentha suaveolens; Morphology; Peppermint; Phenotypes; Piperitenone oxide; Plant Genetics and Genomics; Plant Physiology; Plant Sciences; Plant Systematics/Taxonomy/Biogeography; Ploidy; Research Article; Species; Verticillium wilt
• ISSN: 0925-9864; 1573-5109
• DOI: 10.1007/s10722-019-00750-4

The Mentha germplasm collection housed at the USDA National Clonal Germplasm Repository is a valuable source of diversity for genetic studies and mint breeding. We surveyed phenotypes and genotypes of accessions belonging to two species ancestral to commercial peppermint: M. aquatica and M. suaveolens . Morphology, ploidy, essential oil composition, and relative Verticillium wilt resistance were assessed. Genotyping with simple sequence repeat (SSR) markers was performed in order to establish a set of informative markers for distinguishing accessions from each other. M. suaveolens accessions were triploid or tetraploid, while M. aquatica accessions were octoploid or nonaploid. Holoploid genome sizes differed significantly among accessions within both species. Half of the M. aquatica accessions had (+)-menthofuran as the primary oil constituent, while other accessions showed atypical oil profiles. Most M. suaveolens accessions had high levels of either piperitenone oxide, (−)-carvone, or trans -piperitenone oxide. M. aquatica accessions showed a range of Verticillium wilt resistance to susceptibility, while most M. suaveolens accessions were highly wilt-resistant. Results from genotyping the accessions with nine SSR markers distinguished three groups: one mainly M. suaveolens , one mostly M. aquatica , and one with a mixture of the species. This study enables updates of accession descriptions in the Germplasm Resources Information Network database, and increases the utility of the Mentha collection to the research community.