Isoenzyme diversity in Reynoutria taxa: escape from sterility by hybridization
The genus Reynoutria (Polygonaceae) is represented by four taxa in the Czech Republic – R. japonica var. japonica (EPPO list of invasive alien plants) and compacta, R. sachalinensis (EPPO list of invasive alien plants) and R. x bohemica (EPPO list of invasive alien plants). Using isoenzyme analysis, the degree of genotype variability in all taxa was determined and comparisons were made between clones of R. japonica var. japonica from the Czech Republic and United Kingdom. While the rarely occurring tetraploid variety R. japonica var. compacta possesses low variability, the octoploid female clone of R. japonica var. japonica is genetically uniform in the 93 clones sampled and belongs to the same genotype that is present throughout Europe. R. japonica var. japonica can be fertilized by the pollen of tetraploid R. sachalinensis and a hexaploid hybrid R. x bohemica is produced. In R. sachalinensis, 16 genotypes were found in the 50 clones sampled. R. x bohemica is genetically the most diverse taxon in the study area, with 33 genotypes recorded among 88 clones sampled.
Mandak M, Bimova K, Pysek P, Stepanek J, Plackova I (2005) Isoenzyme diversity in Reynoutria (Polygonaceae) taxa: escape from sterility by hybridization. Plant Systematics and Evolution, 253, 219-230.