Submitted to: Journal of Environmental Horticulture
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/7/2005
Publication Date: 9/30/2005
Citation: Pooler, M.R., Townsend, A.M. 2005. DNA fingerprinting of clones and hybrids of American elm and other elm species with AFLP markers. Journal of Environmental Horticulture. 23:113-117. Interpretive Summary: Elms have been widely used as urban trees because they can withstand numerous environmental stresses, including air pollution, deicing salts, soil compaction, drought, and flooding. In the past several decades, Eurasian hybrids have largely replaced American elms due to the susceptibility of American elm to Dutch elm disease. Recent breeding efforts using American elm and other species have resulted in the release of several disease-tolerant selections that have fueled a renewed interest in elms among nursery professionals and the general public. This study provides data on the genetic relationships among 19 clones of American elm and information on the identity of other popular accessions using the AFLP technique of DNA fingerprinting.
Technical Abstract: The elms represent a diverse group of widely distributed temperate trees that are valued for forest products as well as landscape plants. Genetic diversity was examined among 43 Ulmus accessions, including 19 accessions of American elm and seven other species. Data from 135 markers from five AFLP primer pairs were used to estimate genetic similarity among accessions and to construct a UPGMA-derived dendrogram. While the species clusters were generally well-resolved, the relationships among clones and hybrids of American elm were less distinct. Our data provides some evidence to support the hybrid origin of two previously unverified U. parvifolia x U. americana clones, and provides evidence that the new clone N3487 ('Jefferson'), an elm whose origin has been questioned in the past, is an American elm.