@article{EnsslinSandnerMatthies2011,
  author    = {Ensslin, Andreas and Sandner, Tobias M. and Matthies, Diethart},
  title     = {Consequences of ex situ cultivation of plants genetic diversity, fitness and adaptation of the monocarpic Cynoglossum officinale L. in botanic gardens},
  series = {: an international journal},
  volume    = {144},
  journal   = {: an international journal},
  number    = {1},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0006-3207},
  doi       = {10.1016/j.biocon.2010.09.001},
  pages     = {272 -- 278},
  year      = {2011},
  abstract  = {Ex situ collections in botanic gardens have great potential in contributing to the conservation of rare plants. However, little is known about the effects of cultivation on the genetic diversity and fitness of garden populations, about genetic changes due to unconscious selection and potential adaptation to the artificial conditions. We compared the genetic variability and fitness of the rare, short-lived perennial Cynoglossum officinale from 12 botanic gardens and five natural populations in Germany. Genetic variability was assessed with eight nuclear microsatellites. Plants were grown in a common garden and performance was measured over 2 years. Mean genetic diversity was very similar in botanic garden and natural populations. However, four of the garden populations exhibited no genetic variability at all. Moreover, the genetic diversity of garden populations decreased with increasing duration of cultivation, indicating genetic drift. Plant performance from natural and garden populations in terms of growth, flowering and seed production was similar and in garden populations only seed mass was strongly related to genetic diversity. Several lines of evidence indicated genetic changes in garden populations in response to cultivation. Seed dormancy was strongly reduced in garden populations, and in response to nutrient addition garden plants increased the size of their main inflorescence, while wild plants increased the number of inflorescences. These changes could be maladaptive in nature and reduce the suitability of garden populations as a source for reintroductions. We suggest that botanic gardens should pay more attention to the problem of potential genetic changes in their plant collections.},
  language  = {en}
}
@unpublished{EnsslinTschoepeBurkartetal.2015,
  author    = {Ensslin, Andreas and Tschoepe, Okka and Burkart, Michael and Joshi, Jasmin Radha},
  title     = {Fitness decline and adaptation to novel environments in ex situ plant collections: Current knowledge and future perspectives},
  series = {: an international journal},
  volume    = {192},
  journal   = {: an international journal},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0006-3207},
  doi       = {10.1016/j.biocon.2015.10.012},
  pages     = {394 -- 401},
  year      = {2015},
  abstract  = {The conservation of rare plant species as living collections in botanic gardens and arboreta has become an established tool in the battle against worldwide species' extinctions. However, the establishment of ex situ collections with a high conservation value requires a sound understanding of the evolutionary processes that may reduce the suitability of these collections for future reintroductions. Particularly, risks such as fitness decline of cultivated plants over time, trait shifts and loss of adaptation to the original habitat due to changes in selection regimes have rarely been addressed so far. Based on a literature review and results of our own project we show that genetic drift can lead to fitness decline in ex situ cultivated plants, but these drift effects strongly depend on the conditions and cultivation history in the ex situ facility. Furthermore, we provide evidence that shifts in traits such as germination and flowering time, and a decrease in stress tolerance to drought and competition can reduce the conservation value of ex situ collections. These threats associated with ex situ conditions require more attention by researchers, curators and conservationists. We need to increase knowledge on traits that are subject to novel selection pressures in ex situ collections, and to define population sizes that prevent genetic drift. Establishing conservation networks with replicated collections across gardens and balancing the seed contribution of mother plants to the next generation within a collection are suggested as first steps to increase the conservation value of ex situ plant collections. (C) 2015 Elsevier Ltd. All rights reserved.},
  language  = {en}
}