Open AccessThis article is
- freely available
Phylogeny of Cirsium spp. in North America: Host Specificity Does Not Follow Phylogeny
Biology Department, American University, 4400 Massachusetts Ave. NW, Washington, DC 20016, USA
Sunflower and Plant Biology Research Unit, USDA-Agricultural Research Service, 1605 Albrecht Blvd, Fargo, ND 58102, USA
* Author to whom correspondence should be addressed.
Received: 30 August 2012; in revised form: 11 October 2012 / Accepted: 17 October 2012 / Published: 24 October 2012
Abstract: Weedy invasive Cirsium spp. are widespread in temperate regions of North America and some of their biological control agents have attacked native Cirsium spp. A phylogenetic tree was developed from DNA sequences for the internal transcribed spacer and external transcribed spacer regions from native and non-native Great Plains Cirsium spp. and other thistles to determine if host specificity follows phylogeny. The monophyly of Cirsium spp. and Carduus within the tribe Cardinae was confirmed with native North American and European lineages of the Cirsium spp. examined. We did not detect interspecific hybridization between the introduced invasive and the native North American Cirsium spp. Selected host-biological control agent interactions were mapped onto the phylogenic tree derived by maximum likelihood analysis to examine the co-occurrence of known hosts with biological control agents. Within Cirsium-Cardueae, the insect biological control agents do not associate with host phylogenetic lines. Thus, more comprehensive testing of species in host-specificity trials, rather than relying on a single representative of a given clade may be necessary; because the assumption that host-specificity follows phylogeny does not necessarily hold. Since the assumption does not always hold, it will also be important to evaluate ecological factors to provide better cues for host specificity.
Keywords: biological control; Canada thistle; Cirsium; Cirsium arvense; phylogeny; thistles; weed
Citations to this Article
Cite This Article
MDPI and ACS Style
Slotta, T.A.B.; Horvath, D.P.; Foley, M.E. Phylogeny of Cirsium spp. in North America: Host Specificity Does Not Follow Phylogeny. Plants 2012, 1, 61-73.
Slotta TAB, Horvath DP, Foley ME. Phylogeny of Cirsium spp. in North America: Host Specificity Does Not Follow Phylogeny. Plants. 2012; 1(2):61-73.
Slotta, Tracey A.B.; Horvath, David P.; Foley, Michael E. 2012. "Phylogeny of Cirsium spp. in North America: Host Specificity Does Not Follow Phylogeny." Plants 1, no. 2: 61-73.