Location: Dairy Forage ResearchTitle: DNA Polymorphisms Reveal Geographic Races of Reed Canarygrass) Author
Submitted to: Crop Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 4/22/2009
Publication Date: 10/22/2009
Citation: Casler, M.D., Phillips, M., Krohn, A.L. 2009. DNA Polymorphisms Reveal Geographic Races of Reed Canarygrass. Crop Science. 49:2139-2148. Interpretive Summary: Reed canarygrass is native to the USA, but it has gained a reputation as an "invasive" species. Many ecologists and land managers are convinced that this is due to an introduced "invasive" or "aggressive" genotype from Europe or to super hybrids between native and European types. In order to test this hypothesis, we need to find true native reed canarygrass plants. In this research, we document the tentative classification of three old strains as likely natives that predate the introduction of European types of reed canarygrass. This research will impact land managers, conservationists, and ecologists concerned with wetlands and invasive species.
Technical Abstract: Reed canarygrass (Phalaris arundinacea L.) is a cool-season perennial with a circumglobal distribution in the northern hemisphere, native to Europe, Asia, and North America. Repeated introductions of European germplasm into North America have created confusion over the origins of reed canarygrass germplasm found in wetlands, pastures, and breeding programs. The objectives of this study were to identify sources of DNA marker variation among reed canarygrass cultivars from Europe and North America and between land races and improved cultivars from North America. Analysis of 205 reed canarygrass plants from 15 cultivars based on 102 amplified fragment length polymorphic (AFLP) DNA markers revealed two groups of cultivars. One group consisted of three closely related but geographically diverse North American land races that were completely separated from all other plants in only two dimensions of the AFLP incidence matrix. The complete discrimination of these plants from all European plants suggests their possible origin from native North American germplasm. These results were supported by cpDNA analysis, which additionally revealed separation of a Scandinavian cytoplasmic race from the continental European cytoplasmic race. This is the strongest evidence to date suggesting that native North American reed canarygrass germplasm has been preserved within cultivars of this species.