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1.
Spanish territories contain many of the hot spots of plant biodiversity among European countries. Most of the Spanish territory is found in the Mediterranean basin and in the Canary Islands, a region of great floral singularity and diversity (Macaronesian bioregion). Therefore, an important effort must be made to contribute to its conservation. Several strategies can be considered, but seed conservation under standard conditions is the most resource-efficient method. However, the application of this methodology is not always possible for recalcitrant seeds or species for which vegetative propagation is necessary or convenient under some circumstances. Micropropagation is one of the measures suggested for preserving endangered species. During the 1990s, several in vitro culture protocols for Spanish endemics were established. The main purpose of this strategy was to obtain a considerable number of individuals to reduce the loss of natural populations. Likewise, diverse slow growth protocols were developed for this material. However, these efforts usually did not lead to the establishment of in vitro collections. The advantages and disadvantages of the in vitro conservation strategy will be reviewed for some cases. The establishment of the in vitro protocols together with the development of cryopreservation techniques created the ideal conditions to generate cryogenic collections. In this paper, we review the knowledge and experience accumulated during the last decades in micropropagation, slow growth, and cryopreservation for Spanish plant wild species. Their application in the development ex situ collections and their contribution toward an integrated system to conserve threatened species will be discussed.  相似文献   

2.
The latest IUCN statistics show that of over 12,000 plant species, 70% are threatened, 19% are critically endangered and 28 species are extinct in the wild. Target 8 of the Global Strategy for Plant Conservation (GSPC) highlights the importance of ex situ conservation of critically endangered plants. Long-term germplasm storage for species with recalcitrant seeds needs alternative measures. In vitro methods complement seed banking and other ex situ measures and are vital for long-term conservation. Conservation Biotechnology at RBG Kew is currently working on a number of rare and threatened recalcitrant species from biodiversity-rich areas of the world to develop good quality in vitro propagules for cryopreservation, recovery and restoration projects. The importance of successful in vitro propagation methods, transplantation technologies, cryopreservation and international networking for the integrated conservation of these species are discussed in detail.  相似文献   

3.
The use of ex situ techniques for the conservation of threatened plants has been increasing over the past decades. Cryopreservation is often used for the long-term storage of plant germplasm where conventional methods (i.e. seedbanking) are inappropriate. Simple encapsulation–dehydration protocols were developed for the cryopreservation of bryophytes at The Royal Botanic Gardens, Kew, as part of an ex situ project for the conservation of UK threatened species. The applicability of these methods was tested on 22 species with a broad range of ecological requirements and found to be highly successful across the board. Regeneration rates from frozen material were >68% for all species tested and half had regeneration rates of 100%. The high regeneration rate and broad applicability of the protocols across a range of species was attributed to a combination of the inherent totipotency of bryophytes and the in-built recovery periods in the pre-treatment protocol. In conclusion, bryophytes are well suited to cryopreservation and such techniques would be applicable for the long-term storage of similar conservation collections across the globe.  相似文献   

4.
Conservation In vitro of threatened plants—Progress in the past decade   总被引:1,自引:0,他引:1  
Summary In vitro techniques have found increasing use in the conservation of threatened plants in recent years and this trend is likely to continue as more species face risk of extinction. The Micropropagation Unit at Royal Botanic Gardens, Kew, UK (RBG Kew) has an extensive collection of in vitro plants including many threatened species from throughout the world. The long history of the unit and the range of plants cultured have enabled considerable expertise to be amassed in identifying the problems and developing experimental strategies for propagation and conservation of threatened plants. While a large body of knowledge is available on the in vitro culture of plants, there are limited publications relating to threatened plant conservation. This review highlights the progress in in vitro culture and conservation of threatened plants in the past decade (1995–2005) and suggests future research directions. Works on non-threatened plants are also included wherever methods have applications in rare plant conservation. Recalcitrant plant materials collected from the wild or ex situ collections are difficult to grow in culture. Different methods of sterilization and other treatments to establish clean material for culture initiation are reviewed. Application of different culture methods for multiplication, and use of unconventional materials for rooting and transplantation are reviewed. As the available plant material for culture initiation is scarce and in many cases associated with inherent problems such as low viability and endogenous contamination, reliable protocols on multiplication, rooting, and storage methods are very important. In this context, photoautotrophic micropropagation has the potential for development as a routine method for the in vitro conservation of endangered plants. Long-term storage of material in culture is challenging and the potential applications of cryopreservation are significant in this area. Future conservation biotechnology research and its applications must be aimed at conserving highly threatened, mainly endemic, plants from conservation hotspots.  相似文献   

5.
In vitro culture techniques are usually employed for ex situ conservation of endangered plant species. However, encapsulation to preserve threatened bryophytes is scarcely used, and only as a pretreatment prior to cryopreservation. In our study, two different methods of germplasm conservation, involving calcium-alginate encapsulation of moss material, were assessed. The plant material used was gametophyte buds (gametophores) of Splachnum ampullaceum Hedw., a rare species of moss. Moss regeneration was evaluated at different periods of time to examine the efficacy of the technique for moss germplasm conservation. The effects of encapsulation and cold storage on developmental parameters such as protonematal colony diameter, bud length, and number of buds were also studied. The results suggest that moss encapsulation with no prior treatment may be a suitable method for germplasm conservation during long periods of time. With our method survival rates as high as 50% could be reached after 2.5 years of cold storage versus 0% of 24-h cryopreserved beads. This technique together with cold storage, avoiding freezing, may be especially important in desiccation intolerant mosses.  相似文献   

6.
Europe has the greatest concentration of botanic gardens in the world, they cultivate extensive collections of plants that include samples of European threatened plant species. This study looks at the effectiveness of these collections in supporting species conservation. A three part study is presented: (1) the results of a survey and assessment of threatened plants in botanic gardens, as defined by the Bern Convention; (2) case studies illustrating current issues in the ex situ management of European threatened plant species; and (3) presentation of policy recommendations on further improving botanic garden contributions to European plant conservation. The survey indicated that of 119 European botanic gardens in 29 European countries, 105 are cultivating 308 of the 573 threatened plant species listed by the Bern Convention. The survey identified 25 botanic gardens in 14 countries undertaking 51 conservation projects focused on 27 Bern listed species. In particular this survey has established that the majority of taxa are held in a small number of collections, dominated by non-wild origin accessions, and are not adequately documented. The majority of specimens in botanic gardens are cultivated out of the range country and not contributing to a specific conservation project. We review the genetic representation and documentation of origin in collections. Existing plant collections contain representatives of populations, now lost in the wild and maintain samples of at least nine European plant taxa identified as 'Extinct in the Wild'. However, inadequate standards of record keeping has compromised the conservation value of many collections. We highlight the dangers of hybridisation and disease in ex situ collections. The results suggest that botanic garden collections are skewed towards horticulturally robust and ornamental species and do not fully reflect priorities as defined by the Bern Convention. Recognising the limitations of traditional botanic garden collections we propose that botanic gardens more effectively utilise their two core competencies, namely scientific horticulture and public display and interpretation. The unique horticultural skills resident in European botanic gardens could be more effectively utilised through the application of horticulture to the management of wild populations.Journal of the Royal Horticultural Society  相似文献   

7.
Maintaining living ex situ collections is one of the key conservation methods in botanic gardens worldwide. Despite of the existence of many other conservation approaches used nowadays, it offers for many endangered plants an important insurance policy for the future, especially for rare and threatened relict trees. The aim of this research was to investigate the global extent of living ex situ collections, to assess and discuss their viability and inform the development of conservation approaches that respond to latest global conservation challenges. We used as a model taxon the tree genus Zelkova (Ulmaceae). The genus includes six prominent Tertiary relict trees which survived the last glaciation in disjunct and isolated refugial regions. Our comprehensive worldwide survey shows that the majority of botanic institutions with Zelkova collections are in countries with a strong horticultural tradition and not in locations of their origin. More importantly, the acutely threatened Zelkova species are not the most represented in collections, and thus safeguarded through ex situ conservation. Less than 20% of the ex situ collections surveyed contain plant material of known wild provenance while the majority (90%) of collections are generally very small (1–10 trees). Botanic gardens and arboreta particularly in regions where iconic relict trees naturally occur should play a vital role in the conservation of these species. The coordination of conservation efforts between gardens has to be enhanced to prioritise action for the most threatened relict trees. Large scale genetic studies should be undertaken, ideally at genus level, in order to verify or clarify the provenance of ex situ collections of relict trees in cultivation. For the most threatened relict tree genera, well-coordinated specialist groups should be created.  相似文献   

8.
The value of ex situ plant collections for conservation is increasingly recognised. The Royal Botanic Gardens, Kew (RGB, Kew) has been pioneering methods for the development of such collections with the establishment of the Millennium Seed Bank and a project for the ex situ conservation of threatened UK bryophytes (mosses, liverworts, hornworts). A broad range of bryophytes are currently held in a tissue culture collection at RBG, Kew on sucrose-free ¼ or ½ Murashige &; Skoog or Knops minimal medium. The efficacy of the novel sterilising agent Sodium dichloroisocyanurate (NaDCC) was tested on a range of taxa, utilising a variety of bryophytic initiation material. Concentrations of 1% (w/v) for 3 min and 0.5% (w/v) for 2 min, without the addition of detergent, were found to be successful in initiating cultures from sporophytes and leafy gametophores respectively. Initiation of cultures from wild-collected sporophytes was more successful than from wild-collected gametophores. However, pre-culturing of gametophore material was found to enhance success rate of procedures. Transferring visibly clean material away from contamination post-initiation was also determined to increase protocol success rate. The ability of the biocide Plant Preservative MixtureTM (PPMTM) to control fungal and bacterial contamination in bryophyte protonemal cultures was also tested, but not found to be suitable. However, results obtained indicated that contamination may confer resistance on the moss against the phytotoxic effects of the biocide. Methods developed have wider applicability for the establishment of in vitro collections of other threatened plants.  相似文献   

9.
Island populations are often thought to be more susceptible to the loss of genetic diversity as a consequence of limited population size and genetic drift, greater susceptibility to detrimental stochastic events and low levels of immigration. However the geographic isolation of islands may create refuges for native crop species whose genetic diversity is threatened from the genetic erosion occurring in mainland areas as a result of crop-wild gene flow and genetic swamping. Many UK islands remain uncharacterised in terms of plant genetic diversity. In this study we compared the genetic diversity of mainland populations and landraces of Trifolium repens with wild populations collected from the islands surrounding the UK, including the island of Hirta in the St Kildan archipelago. Individuals from St Kilda represent a unique conservation resource, with populations both highly differentiated from UK mainland populations and genetically distinct from cultivated varieties, whilst able to retain diversity through limited human influence on the islands. In contrast, there is relative genetic similarity of wild UK populations to cultivated forms highlighted in mainland populations, but with geographic barriers preventing complete homogenisation of the mainland UK genepool. We underline the need for conservation priorities to include common species that are threatened by gene flow from cultivation, and draw attention to the potential of islands to preserve natural levels of genetic diversity.  相似文献   

10.
The European flora is of global significance but many species are facing an ever increasing range of threats, especially the growing impacts of climate change. While various estimates have been made for the number of threatened plant species in Europe, an up-to-date European plant Red List does not presently exist. Target 8 of the Global Strategy for Plant Conservation (GSPC) calls for 60% of threatened plant species to be conserved in ex situ collections by 2010. In the absence of a European plant Red List, it is difficult to monitor progress at the regional level towards this target. To address this gap Botanic Gardens Conservation International (BGCI) has developed a consolidated list of European threatened species as a step towards a formal Red List. The database consists of national Red List data from 28 European countries and includes records for over 11,000 taxa. National Red List data were supplemented by information on the critically endangered plants of Europe provided by the Museum National d’Histoire Naturelle/European Topic Centre on Biological Diversity and the Conservatoire Botanique National de Brest. A list of regionally threatened species was extracted from the database and screened against BGCI’s database of plants in cultivation in botanic gardens (PlantSearch) and ENSCONET’s (European Native Seed Conservation Network) database of plants conserved in European seed banks. This analysis revealed that 42% of European threatened species are currently included in ex situ conservation programmes in Europe.  相似文献   

11.
Climate change, alien species, and use of land for intensive farming and development are causing severe threat to the plant genetic diversity worldwide. Hence, conservation of biodiversity is considered fundamental and also provides the livelihoods to millions of people worldwide. Medicinal plants play a key role in the treatment of a number of diseases, and they are only the source of medicine for majority of people in the developing world. The tropical regions of the world supply the bulk of current global demand for “natural medicine,” albeit with increasing threat to populations in the world and its genetic diversity. India is a major center of origin and diversity of crop and medicinal plants. India poses out 20,000 species of higher plants, one third of it being endemic and 500 species are categorized to have medicinal value. The Western Ghats is one of the major repositories of medicinal plants. It harbors around 4,000 species of higher plants of which 450 species are threatened. Currently, the number of species added to the red list category in this region is increasing, and the valuable genetic resources are being lost at a rapid rate. Demand for medicinal plants is increasing, and this leads to unscrupulous collection from the wild and adulteration of supplies. Providing high-quality planting material for sustainable use and thereby saving the genetic diversity of plants in the wild is important. During the last 25 years of intensive research, Tropical Botanic Garden and Research Institute has developed in vitro protocol for rapid regeneration and establishment of about 40 medicinally important rare and threatened plants of Western Ghats. In situ conservation alone would not be effective in safeguarding these important species. Thus, utilizing the biotechnoligical approach to complement ex situ conservation program is becoming vital. Propagating biotechnology tools in plant conservation program is a prerequisite to succeed in sustainable use and to complement the existing ex situ measures. In addition to propagation, storage of these valuable genetic resources is equally important. In vitro slow growth of 35 species and cryopreservation using embryo/meristem/seed in 20 different species of rare medicinal plants of this region is accomplished. Plants developed in vitro of ten medicinal plants, which have restricted distribution, were reintroduced in the natural habitat as well.  相似文献   

12.
Freshwater pearl mussels (Margartifera margaritifera L.) are among the most critically threatened freshwater bivalves worldwide. The pearl mussel simultaneously fulfils criteria of indicator, flagship, keystone and umbrella species and can thus be considered an ideal target species for the process conservation of aquatic ecosystem functioning. The development of conservation strategies for freshwater pearl mussels and for other bivalve species faces many challenges, including the selection of priority populations for conservation and strategic decisions on habitat restoration and/or captive breeding. This article summarises the current information about the species’ systematics and phylogeny, its distribution and status as well as about its life history strategy and genetic population structure. Based on this information, integrative conservation strategies for freshwater mollusc species which combine genetic and ecological information are discussed. Holistic conservation strategies for pearl mussels require the integration of Conservation Genetics and Conservation Ecology actions at various spatial scales, from the individual and population level to global biodiversity conservation strategies. The availability of high resolution genetic markers for the species and the knowledge of the critical stages in the life cycle, particularly of the most sensitive post-parasitic phase, are important prerequisites for conservation. Effective adaptive conservation management also requires an evaluation of previous actions and management decisions. As with other freshwater bivalves, an integrative conservation approach that identifies and sustains ecological processes and evolutionary lineages is urgently needed to protect and manage freshwater pearl mussel diversity. Such research is important for the conservation of free-living populations, as well as for artificial culturing and breeding techniques, which have recently been or which are currently being established for freshwater pearl mussels in several countries.  相似文献   

13.
The importance of in vitro tools to complement other ex situ methods for saving plants from extinction is more relevant than ever before. More than 50% of the world’s plant species are endemic to the 34 global biodiversity hotspots (GBHs), each holding at least 1,500 endemic plant species. In addition, a large number of small islands hold a number of endemic species on the brink of extinction. Conservation support concentrating more on these hotspots and small islands would significantly reduce the loss of species that is currently occurring. In the majority of these cases, the resources are either locally scarce or difficult to access for in vitro conservation to support other ex situ measures. Most island countries are small, and their geographical position is a stumbling block to initiate active partnerships with other countries when they need to use in vitro tools to rescue plants that produce recalcitrant seeds/spores or propagate only by vegetative means. However, many biodiversity hotspot countries have facilities and expertise, and they concentrate on their own flora for in vitro conservation programmes. For decades, because of the grave threat these plants face, the Conservation Biotechnology Unit, previously known as the Micropropagation Unit, at Royal Botanic Gardens Kew (RBG Kew) has been at the forefront of assisting countries to save their valuable biodiversity through both in situ and ex situ methods. Approaches mentioned here highlight work on recalcitrant ferns from GBHs and small islands. Source materials from recalcitrant species, either spore or seed and in some cases vegetative material, need to be used immediately after collection for tangible results in vitro. This becomes more difficult when only a few plants or small populations are left in the wild. The task becomes harder when available material is small in quantity, and there is greater restriction on the use of available genetic diversity in the wild. This paper highlights the importance of proper collection measures, in vitro culture procedures and cryopreservation and methods for the integrated conservation of threatened ferns from both GBHs and small islands. The importance of international networking to achieve these conservation goals also will be discussed.  相似文献   

14.
Summary

Conservation of plants is now viewed as a major priority for botanic gardens. However, few practical initiatives to conserve Scotland's threatened flora have so far been undertaken in Scotland. With the present financial uncertainty of Scotland's botanic gardens and the low priority given by them to the ex situ conservation of threatened Scottish plants, the scope for further conservation activities is limited. Long-term preservation of living material of a large number of threatened Scottish species in Scotland's botanic gardens is unlikely to be undertaken by any of them in the present climate. New practical initiatives must: 1) be self-financing; 2) have low maintenance costs; and 3) further the public role of botanic gardens in education. The best way forward is to develop areas using Scottish plants of wild origin in an informal garden setting to create unique wildlife habitats within the botanic garden itself. Threatened species could be included where the habitat allowed. Such areas would provide ideal opportunities for environmental study programmes and ecological projects and, at the same time, would widen the educational role of the botanic garden.  相似文献   

15.
We present the EU LIFE PonDerat project, which is aimed at restoring the natural ecosystems of the Pontine Archipelago, a group of islands located off the western coast of Italy. The spread of invasive species is a major environmental threat on these islands, which are rich in rare habitats and endemic species and are important sites for the conservation of Mediterranean biodiversity. The project focuses on the conservation of species and habitats that are protected by EU laws but are currently threatened by introduced plants and animals. The main targets of the control measures are black rats, feral goats, mouflons and invasive plants of the genus Carpobrotus. Conservation measures focus on the shearwaters Puffinus yelkouan and Calonectris diomedea, which are endemic to the Mediterranean and are listed in Annex I of the European Bird Directive. Conservation measures also focus on island habitats of great biogeographical value, which are listed in Annex I of the European Habitats Directive and are seriously threatened by introduced herbivores and by invasive plants. The main outcome expected from this project is that the restoration of ecosystem functions will enhance the breeding success and population size of shearwaters and lead to the recovery of target habitats.  相似文献   

16.
Conservation geneticists make inferences about their focal species from genetic data, and then use these inferences to inform conservation decisions. Since different biological processes can produce similar patterns of genetic diversity, we advocate an approach to data analysis that considers the full range of evolutionary forces and attempts to evaluate their relative contributions in an objective manner. Here we collect data from microsatellites and chloroplast loci and use these data to explore models of historical demography in the carnivorous Pitcher Plant, Sarracenia alata. Findings indicate that populations of S. alata exhibit high degrees of population genetic structure, likely caused by dispersal limitation, and that population sizes have decreased in western populations and increased in eastern populations. These results provide new insight to the management and conservation of plants restricted to small, declining populations isolated in increasingly scarce and highly threatened habitat, including other rare and endangered species of Sarracenia.  相似文献   

17.
Fragmentation is predicted to increase inbreeding depression and lower the evolutionary potential of organisms by disrupting dispersal. Trees may be more resilient to fragmentation effects due to potential long-distance dispersal mechanisms that genetically connect fragments. Polylepis woodlands in the high Andes are highly fragmented and are currently the focus of reforestation and conservation efforts. Polylepis multijuga Plige (Rosaceae) is a threatened, endemic tree species in the northern Andes of Peru. Samples were collected from 371 adult trees in nine forest fragments separated by 0.5–80 km and genotyped at amplified fragment length polymorphism loci (AFLP) and chloroplast intergenic regions to determine the connectedness of fragments and their suitability for collecting seed for restoration efforts. P. multijuga is wind-pollinated and dispersed; however, genetic diversity in P. multijuga was about half that reported for other wind-pollinated species. Genetic spatial autocorrelation and patterns of chloroplast and AFLP diversity suggest seed dispersal is very limited and that wind dispersed pollen does not effectively connect all fragments. Conservation of this species will require reforestation efforts and possibly augmentation of some fragments to increase their genetic diversity. Collecting seed from multiple large fragments and from individuals separated by at least 25 m within fragments would maximize the genetic diversity of seed collections for reforestation or augmentation. Future studies of this and other Polylepis species should determine how complex topography may affect wind mediated dispersal between fragments and patterns of genetic diversity.  相似文献   

18.
Worldwide about one third of all plant species is estimated to be threatened with extinction. Plants are generally under-represented in conservation. However, the global strategy for plant conservation (GSPC) sets forth 16 targets to halt the current and continuing loss of plant diversity within a framework for actions at global, regional, national and local levels. Target 8 of the GSPC directs that at least 75 % of threatened plant species be present in ex situ collections by 2020, but this target is far from being met. By analyzing where gaps in ex situ collections and research exist relative to diversity hotspots of threatened species, it is possible to identify and prioritize action. We undertake a gap analysis of ex situ collection needs in the genus Magnolia, a relatively well-known and valuable genus. Results indicate three main areas of biodiversity (China, Vietnam and Colombia) for the endangered Magnolia taxa. The present paper provides a critical overview of recent conservation activities carried out in the genus Magnolia throughout the world, focusing on genetic diversity analyses of the species.  相似文献   

19.
G. Bedini  A. Carta 《Kew Bulletin》2010,65(4):649-654
The ex situ conservation of plant species is a challenge for all signatories of the Convention on Biological Diversity to meet. In Italy, all conservation-related issues are supervised by the Ministry for the Environment and Protection of Land and Sea, but so far no national plan has been drafted, let alone funded, for ex situ plant conservation. As a contribution towards the establishment of a scientifically based policy, a national project has been launched, under the coordination of the Botanic Garden of Palermo. In its framework, the Botanic Garden of Pisa is developing a set of criteria for assessing Italian ex situ collections of threatened plant species. The criteria will be applied to datasets obtained by the Italian seedbanks through questionnaires. Requested data include resources and procedures, documentation systems, facilities and accessions. The expected results consist of the production of printed or electronic material concerning a) the technical-scientific profile of the Italian seed banks and of their collections; b) the ecogeographic profile of seed collections of selected species and c) the evaluation of the method used for gathering and analysing data. The project is currently under way and the results are due by September 2010. The documents and protocols which will be produced within the project will enable a stronger interaction of the Italian seed banks with other national and European seed bank networks.  相似文献   

20.
The European otter (Lutra lutra) is a focus for conservation efforts throughout Europe due to a population decline in recent decades and because of its importance as a biological indicator of the health of rivers and waterways. The aim of this study was to aid the conservation of this species by adding genetic information from samples originating in the United Kingdom (UK), to help build up a picture of the phylogeographic structure of the European otter throughout Europe. This was done by a comparison of 299 base pairs of the mitochondrial DNA control region. Four haplotypes were identified in the UK, one of which has not been found outside the west of the UK in the wild, and one of which was unique. Populations in the UK, and in particular the west were shown to have a higher haplotype diversity than previously found for the European otter in Europe (= 0.7338 for the 58 UK otters sampled in this study) and an overall nucleotide diversity of π = 0.003. The western UK population was shown to have a high level of genetic distinctiveness. We discuss possible contributory population processes, the importance of the western UK population for the future conservation of the species and comment on future conservation strategies.  相似文献   

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