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- Hagenblad, Jenny, et al.
(författare)
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Low genetic diversity despite multipleintroductions of the invasive plant species Impatiens glandulifera in Europe
- 2015
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Ingår i: BMC Genetics. - : Springer Science and Business Media LLC. - 1471-2156. ; 16:103
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Tidskriftsartikel (refereegranskat)abstract
- Background: Invasive species can be a major threat to native biodiversity and the number of invasive plant speciesis increasing across the globe. Population genetic studies of invasive species can provide key insights into theirinvasion history and ensuing evolution, but also for their control. Here we genetically characterise populations ofImpatiens glandulifera, an invasive plant in Europe that can have a major impact on native plant communities. Wecompared populations from the species’ native range in Kashmir, India, to those in its invaded range, along alatitudinal gradient in Europe. For comparison, the results from 39 other studies of genetic diversity in invasivespecies were collated.Results: Our results suggest that I. glandulifera was established in the wild in Europe at least twice, from an areaoutside of our Kashmir study area. Our results further revealed that the genetic diversity in invasive populations ofI. glandulifera is unusually low compared to native populations, in particular when compared to other invasivespecies. Genetic drift rather than mutation seems to have played a role in differentiating populations in Europe. Wefind evidence of limitations to local gene flow after introduction to Europe, but somewhat less restrictions in thenative range. I. glandulifera populations with significant inbreeding were only found in the species’ native rangeand invasive species in general showed no increase in inbreeding upon leaving their native ranges. In Europe wedetect cases of migration between distantly located populations. Human activities therefore seem to, at leastpartially, have facilitated not only introductions, but also further spread of I. glandulifera across Europe.Conclusions: Although multiple introductions will facilitate the retention of genetic diversity in invasive ranges,widespread invasive species can remain genetically relatively invariant also after multiple introductions. Phenotypicplasticity may therefore be an important component of the successful spread of Impatiens glandulifera across Europe.
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| 2. |
- Lemke, Isgard H., et al.
(författare)
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Patterns of phenotypic trait variation in two temperate forest herbs along a broad climatic gradient
- 2015
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Ingår i: Plant Ecology. - : Springer Science and Business Media LLC. - 1385-0237 .- 1573-5052. ; 216:11, s. 1523-1536
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Tidskriftsartikel (refereegranskat)abstract
- Phenotypic trait variation plays a major role in the response of plants to global environmental change, particularly in species with low migration capabilities and recruitment success. However, little is known about the variation of functional traits within populations and about differences in this variation on larger spatial scales. In a first approach, we therefore related trait expression to climate and local environmental conditions, studying two temperate forest herbs, Milium effusum and Stachys sylvatica, along a similar to 1800-2500 km latitudinal gradient. Within each of 9-10 regions in six European countries, we collected data from six populations of each species and recorded several variables in each region (temperature, precipitation) and population (light availability, soil parameters). For each plant, we measured height, leaf area, specific leaf area, seed mass and the number of seeds and examined environmental effects on within-population trait variation as well as on trait means. Most importantly, trait variation differed both between and within populations. Species, however, differed in their response. Intrapopulation variation in Milium was consistently positively affected by higher mean temperatures and precipitation as well as by more fertile local soil conditions, suggesting that more productive conditions may select for larger phenotypic variation. In Stachys, particularly light availability positively influenced trait variation, whereas local soil conditions had no consistent effects. Generally, our study emphasises that intra-population variation may differ considerably across larger scales-due to phenotypic plasticity and/or underlying genetic diversity-possibly affecting species response to global environmental change.
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