The conservation genetics of two endangered plants of Ontario, Canada, Cirsium pitcheri and Isoetes engelmannii, using nuclear and chloroplast DNA

A two case study approach was utilized to assess the effectiveness of genetic markers as tools for distinguishing between species needing human intervention for survival compared to species simply existing at their range edge. Geopolitical boundaries are used most often in conservation planning, even though these limits generally do not incorporate the entire range of a species. Engelmann's Quillwort (Isoetes engelmannii) and Pitcher's Thistle (Cirsium pitcheri), exist as two transboundary species that are listed as endangered and are located at their range edge in Canada. With the use of specific genetic tools these species that exist under different systems, revealed unique aspects of the genetic variability in rare plant populations in Canada. For example, utilization of the TrnL TrnF intergenic spacer (cpDNA) as well as the LFY homolog (nDNA), allowed for the differentiation between Canadian, and US samples of Isoetes engelmannii. In addition, a species identification tool was developed that allowed for a less invasive, cost effective method of discerning between species within Isoetes a genus where species misidentifications are known to occur. C. pitcheri demonstrated low genetic variability based on heterozygote deficiencies within 14 sites significant heterozygote deficiencies at five sites and, fixed alleles at ten sites. As these species are listed as endangered at both the Provincial and Federal levels of government, recommendations for conservation and future work are discussed.Keywords. Cirsium pitcheri, Pitcher's thistle, Isoetes engelmannii, Engelmann's Quillwort, TrnL TrnF intergenic spacer, LFY homolog, microsatellites, conservation.