Journal Article

Inferring the introduction history of the invasive apomictic grass Cortaderia jubata using microsatellite markers

Lyle, Mark, Okada, Miki, Jasieniuk, Marie

2009

Overview

Reconstructing the introduction history of exotic species is critical to understanding ecological and evolutionary processes that underlie invasive spread and to designing strategies that prevent or manage invasions. The aims of this study were to infer the introduction history of the invasive apomictic bunchgrass Cortaderia jubata and to determine if molecular data support the postulated horticultural origin of invasive populations. Invaded areas in the USA (California, Maui) and New Zealand; native areas in Bolivia, Ecuador and Peru. We used nuclear microsatellite markers to genotype 281 plants from invaded areas in California, Maui and New Zealand, and 77 herbarium specimens from native South America, and compared the genotypic and clonal variation of C. jubata from the invaded and native ranges. Clonal diversity was determined from genotypic diversity using two analytical methods. Invasive C. jubata from invaded regions in California, Maui and New Zealand consisted of the same single clone that probably originated from a single introduced genotype. In contrast, 14 clones were detected in herbarium specimens from the native areas of Bolivia, Ecuador and Peru. The invasive clone matched the most common clone identified in herbarium specimens from southern Ecuador where horticultural stock is presumed to have originated. The lack of clonal and genotypic diversity in invasive plants, but moderately high diversity detected in native plants, indicates a significant reduction in genetic variation associated with the introduction of C. jubata outside of its native range. Based on historical accounts of the horticultural introduction of C. jubata and the results of this study, a severe founder effect probably occurred during deliberate introduction of C. jubata into cultivation. Our results are consistent with the postulated horticultural origin of invasive C. jubata and point to southern Ecuador as the geographical source of invasive populations.

• Publisher: Oxford, UK : Blackwell Publishing Ltd,Blackwell Publishing Ltd,Blackwell Publishing,Blackwell,John Wiley & Sons, Inc
• Subject: Analytical methods / Andean pampas grass / Animal, plant and microbial ecology / Applied ecology / Biodiversity Research / Biological and medical sciences / biological invasions / Bolivia / Botany / California / clonal diversity / clonal variation / clones / Conservation / Cortaderia / Cortaderia jubata / Cultivation / Ecological genetics / Ecological invasion / Ecology / Ecuador / founder effect / Fundamental and applied biological sciences. Psychology / General aspects / Genetic diversity / genetic markers / Genetic variation / genotype / Genotypes / genotypic diversity / grasses / herbaria / Historical account / Horticulture / Indigenous plants / indigenous species / Introduced species / introduction history / Invasions / Invasive plants / Invasive species / Maui / Molecular biology / New Zealand / Nonnative species / Peru / Plants / Population ecology / Population genetics / weed / weeds