Genetic relationships between Heracleum species in its invaded and native ranges
Heracleum mantegazzianum (Apiaceae, EPPO list of invasive alien plants) was introduced into Europe in the XIXth century from the Caucasus and is now widespread and considered invasive in many countries. H. sosnowskyi (EPPO list of invasive alien plants) and H. persicum are also considered invasive. To elucidate genetic relationships between these species and their populations, samples from 72 populations collected from 15 European and Asian countries were analysed. Analysis revealed that plants of each of the three taxa collected in the invaded range were genetically close to those from their native ranges. It also showed close genetic relationships between the three invasive Heracleum species in Europe, particularly between H. mantegazzianum and H. sosnowskyi. High overall genetic diversity was detected in the invaded range. This suggests that rapid evolution, drift and hybridization may have played a role in genetic structuring of invading populations since the introduction of these species into Europe. On the other hand, individual populations in the invaded range had lower within-population variation than populations in the native areas. These results suggest that multiple introductions of all three species into Europe are most likely.
Sources
Jahodová Š, Trybush S, Pyšek P, Karp A (2006) Heracleum in Europe and Asia: genetic relationship between species in invaded and native distribution ranges In: Neobiota. From Ecology to Conservation. 4th European Conference on Biological Invasions. Vienna (Austria), 2006-09-27/29, BfN-Skripten 184: page 158 (abst.).