Ml. Hollingsworth et al., The use of molecular markers to study patterns of genotypic diversity in some invasive alien Fallopia spp. (Polygonaceae), MOL ECOL, 7(12), 1998, pp. 1681-1691
Random amplified polymorphic DNA (RAPDs) and inter-simple sequence repeats
(inter-SSRs) have been used to study clonal growth and hybridization in som
e non-native, gynodioecious, invasive weeds from the genus Fallopia (Polygo
naceae). At the study site (the River Kelvin, Glasgow, UK) a single genotyp
e of Japanese knotweed (Fallopia japonica) was detected, consistent with al
l the individuals sampled being ramets of a single clone. Two genotypes of
giant knotweed (E sachalinensis) were detected, with one genotype accountin
g for all but one of the samples, again indicative of widespread clonal gro
wth. Five genotypes of the hybrid between Japanese and giant knotweed (F. x
bohemica) were recovered. E x bohemica is the only male-fertile taxon pres
ent at the site and it seems probable that at least some of this genetic va
riation is attributable to hybrid fertility. A single plant identified usin
g morphological methods as a backcross between E japonica and E x bohemica
was analysed, and the molecular data were consistent with this theory. A co
mparison of RAPDs and inter-SSRs showed that the two techniques gave data t
hat are broadly congruent, and both techniques showed a similar sensitivity
in the number of genotypes detected.