Genetic analysis of an interspecific hybrid swarm of Populus: occurrence of unidirectional introgression.

P. Keim, K. N. Paige, T. G. Whitham, K. G. Lark

Research output: Contribution to journalArticle

180 Scopus citations


Restriction fragment length polymorphisms were used to distinguish genotypes of two species of Populus, P. fremontii ('Fremont') and P. angustifolia ('narrowleaf'). Both inter- and intraspecific polymorphisms were detected in these cottonwood trees. The interspecific variation was much greater than the intraspecific variation. This permitted identification of parental genotypes within individual trees of a hybrid swarm which exists in an overlap zone between the two species. Within this hybrid swarm, individual trees are either F1 hybrids or backcrosses with a pure 'narrowleaf' parent; no progeny were found that could be attributed to crossing between F1 hybrid trees, or to backcrossing between F1 hybrid trees and 'Fremont'.

Original languageEnglish (US)
Pages (from-to)557-565
Number of pages9
Issue number3
StatePublished - Nov 1989
Externally publishedYes


ASJC Scopus subject areas

  • Genetics

Cite this