ARS | Publication request: When population genetics meets biological control of the invasive swallow-worts (Vincetoxicum nigrum (L.) Moench and V. rossicum (Kleopow) Barbar)

Submitted to: European Weed Research Society Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: January 10, 2010
Publication Date: July 12, 2010
Citation: Bon, M., Jeanneau, M., Jones, W.A., Milbrath, L.R., Sforza, R., Dolgovskaya, M. 2010. When population genetics meets biological control of the invasive swallow-worts (Vincetoxicum nigrum (L.) Moench and V. rossicum (Kleopow) Barbar). 15th European Weed Research Society Symposium Proceedings, Kaspovar, Hungary, 12-15 July 2010.

Technical Abstract: We explored the population genetics of two European swallow-worts belonging to the Apocynaceae that have become established in the eastern United States and Canada. Population genetic data concerning both native and introduced populations are being used to pinpoint introduced population origin, and to examine spread of both species, all data that are getting increasingly important for conducting rigorous specificity tests in the time frame of a biological control program. Population genetics of the weeds in their native and introduced ranges was assessed using chloroplast DNA sequencing and inter simple sequence repeat (ISSR) marker approach. Both species have much lower cpDNA haplotype and ISSR loci diversities in the introduced range relative to the native range, suggesting that the introduction imposed a strong bottleneck in population size. Modern North American populations were compared with historical ones from herbarium collections for reconstructing invasion history of the two weeds. Results confirmed that the historical cpDNA haplotype found in both species was identical to the modern one. For both species, one major genotype was responsible for invasion and spread in North America. Native populations sharing the same exact multilocus genotype detected in introduced populations have already been identified for V. rossicum. Identification of source populations is achieved for V. rossicum but has yet to be found for V. nigrum. By integrating population genetics, the ongoing biological control program using exotic natural enemies is moving forward. Study cases with such extreme lack of variation within invasion process are seldom documented; therefore these two cases represent ideal test assets for theories in evolutionary processes underlying invasiveness.