Author
Greene, Stephanie | |
GRITZENKO, M. - WASHINGTON STATE UNIV. | |
Vandemark, George |
Submitted to: Genetic Resources and Crop Evolution
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/20/2003 Publication Date: 11/1/2003 Citation: Greene, S.L., Gritzenko, M., Vandemark, G.J. Relating morphologic and rapd marker variation to collection site environment in wild populations of red clover (trifolium pratense l.). Genetic Resources and Crop Evolution. Interpretive Summary: Although many traits can be used to describe genetic diversity, attributing variation to environmental adaptation is complex. This paper describes how we compared the results of measuring diversity using morphologic and RAPD markers for 33 wild red clover populations collected from the Caucasus Mountains, Russia. We were interested in comparing how morphologic and RAPD markers diversity corresponded to collection site diversity. We also examined if wild red clover populations collected from sites located in areas more conducive to gene flow (i.e. adjacent to roads, or drainage systems) had the same concordance between morphologic and RAPD markers as populations collected from sites less conducive to gene flow. Morphology clustered the populations into classes that corresponded to three climate regimes. The morphologic and RAPD data did not coincide. Morphologic data corresponded with site data for populations collected at all sites. RAPD data corresponded to site data for only those populations collected at sites not conducive to gene flow. A population's adaptation to collection site needs to be considered in using neutral markers to effectively discriminating geographic differentiation. We discuss the practical lessons of this study on the effective collection, conservation and use of plant genetic resources. Technical Abstract: Although genotypic and phenotypic markers are used to describe genetic diversity, describing patterns of variation attributable to geographic differentiation is complex. We examined concordance between morphologic and RAPD marker classification of 33 wild red clover populations collected from the Caucasus Mountains, Russia and compared how morphologic and RAPD markers differed in their correspondence to collection site attributes. We also examined if wild red clover populations collected from sites located in areas more conducive to gene flow (i.e. adjacent to roads, or drainage systems) had the same concordance between morphologic and RAPD markers as populations collected from sites less conducive to gene flow. We measured 15 morphologic traits in a common garden and carried out a Random Amplified Polymorphic DNA (RAPD) analysis. There was a significant difference among the 33 populations for 14 out of 15 morphological traits. Morphology clustered the populations into classes that corresponded to three climate regimes. Classification schemes generated by morphologic and RAPD data did not coincide. Morphologic data corresponded with site data for populations collected at all sites. RAPD data corresponded to site data for only those populations collected at sites not conducive to gene flow. A population's adaptation to collection site needs to be considered in using neutral markers to effectively discriminating geographic differentiation. We discuss the practical lessons of this study on the effective collection, conservation and use of plant genetic resources. |