Incongruence between cpDNA and nrITS trees indicates extensive hybridization within Eupersicaria (Polygonaceae).

摘要: Interspecific hybridization followed by polyploidization appears to have played a major role in plant diversification, but quantifying the contribution of this mechanism diversification within taxonomically complex clades remains difficult. Incongruence among gene trees can provide critical insights, especially when combined with data on chromosome numbers, morphology, and geography. To further test our previous hypothesis hybrid speciation Persicaria (Polygonaceae), we performed molecular phylogenetic studies using three cpDNA regions nuclear ITS sequences, an emphasis sampling section Eupersicaria. Our analyses revealed conflicts between tree nrITS tree; variety incongruence tests rejected stochastic error as cause most cases. On basis results information hypothesize that origin 10 polyploid species involved interspecific hybridization. also support recognition several previously named been treated belonging other species. Repeated allotetraploidy (as distinct from radiation at tetraploid level) now be key governing challenging group.