Genetic Analysis of an Interspecific Hybrid Swarm of Populus: Occurrence of Unidirectional Introgression |
| |
Authors: | P. Keim K. N. Paige T. G. Whitham K. G. Lark |
| |
Affiliation: | Department of Biology, University of Utah, Salt Lake City 84112. |
| |
Abstract: | 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'. |
| |
Keywords: | |
|
|