Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/7/2005
Publication Date: 2/7/2005
Citation: Slotta, T.A., Horvath, D.P., Foley, M.E. 2005. Survey of genetic markers in assessing variation in Canada thistle of the Northern Great Plains.[Abstract]. Meeting of the Weed Science Society of America. Page No. 48. Interpretive Summary: Canada thistle is a worldwide noxious weed which interferes with agriculture and natural areas. It infests more than 900,000 acres in North Dakota, nearly surpassing leafy spurge as the state's most noxious weed. The plants spread by wind-born seeds and through extensive root system. The current project aims to investigate how Canada thistle has spread throughout the Northern Great Plains. We are using genetic markers, similar to 'DNA fingerprints,' to study the relationships of individuals within and between populations. Populations in North Dakota are more closely related to one another than populations that were studied in Europe.
Technical Abstract: Canada thistle, Cirsium arvense, is a worldwide noxious weed which interferes with crops and negatively impacts non-crop areas. It infests more than 900,000 acres in North Dakota, nearly surpassing leafy spurge as the state's most noxious weed. Populations are established, frequently in disturbed habitats, by wind-born seeds followed by asexual colonization with vegetative buds developing from an extensive root system. It is estimated that one plant can colonize an area 3 to 6 feet in diameter within two years. Prior studies investigating the genetic diversity of C. arvense in Europe indicated that populations sampled were highly diverse, maintained genetic diversity over 3 years, and that clonal reproduction did not significantly contribute to the growth of populations. The current study is investigating the genetic diversity of C. arvense in North Dakota and the Northern Great Plains. Microsatellite markers have been designed; 57% of those surveyed are variable with an average of one polymorphic locus per marker. Inter-simple sequence repeats (ISSRs) were also examined, of which 67% were variable with an average of 2.3 polymorphic loci per marker. Preliminary data indicates that the genetic diversity within populations in North Dakota is lower than that of European populations previously surveyed.