Development of Microsatellite Markers in Symphyotrichum Pilosum and Symphyotrichum Parviceps for Investigation of their Relationship with an Unknown Missouri Glade Aster

Abstract

The genus Symphyotrichum belongs to the family Asteraceae and consists of more than 90 species of plants. It is divided into four subgenera based on morphology and molecular data. There are both annual and perennial plants present in the genus which were earlier regarded as a part of the genus Aster. Most of the plants occur across North America but many species are also common across South America and Eurasia (Brouillet, Semple, Allen, Chambers & Sundberg, 2006). Symphyotrichum parviceps is usually present in the eastern part of United States and is less common than Symphyotrichum pilosum (Nesom, 1995). The purpose of this study is to develop microsatellite markers for S.parviceps and S.pilosum to examine their relationship to an unknown Symphyotrichum species found near Steelville, MO.

Previous work done by Kabjaf (2015) indicated the unknown aster is a dodecaploid (2n=12X=96) and this chromosome number is higher than the known chromosome numbers for S.pilosum (n=16,20,24) and S.parviceps (n=16,24,32) in Missouri. Kabjaf (2015) proposed that the unknown species is a hexaploid variant of S.parviceps and it might either be an autopolyploid of S.parviceps or S.pilosum or an allopolyploid between S.parviceps and S.pilosum. It was hypothesized that the unknown aster is a new species altogether because of the specialized habitat it was collected from.

Internal Transcribed Sequence data could not resolve any differences among the species. Although markers have been developed for different genera of the family, Asteraceae, due to its low level of genetic conservation has restricted transferability of microsatellite markers across different genera (Whitton, Rieseberg & Ungerer, 1997). Presently, there are no microsatellite markers available for these species or even the genus. Development of microsatellite markers would help resolve the relationships among the species and the unknown aster.