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1.

Conservation programmes are always limited by available resources. Careful planning is therefore required to increase the efficiency of conservation and gap analysis can be used for this purpose. This method was used to assess the representativeness of current ex situ and in situ conservation actions of 234 priority crop wild relatives (CWR) in Indonesia. This analysis also included species distribution modelling, the creation of an ecogeographical land characterization map, and a complementarity analysis to identify priorities area for in situ conservation and for further collecting of ex situ conservation programmes. The results show that both current ex situ and in situ conservation actions are insufficient. Sixty-six percent of priority CWRs have no recorded ex situ collections. Eighty CWRs with ex situ collections are still under-represented in the national genebanks and 65 CWRs have no presence records within the existing protected area network although 60 are predicted to exist in several protected areas according to their potential distribution models. The complementarity analysis shows that a minimum of 61 complementary grid areas (complementary based on grid cells) are required to conserve all priority taxa and 40 complementary protected areas (complementary based on existing protected areas) are required to conserve those with known populations within the existing in situ protected area network. The top ten of complementary protected areas are proposed as the initial areas for the development of CWR genetic reserves network in Indonesia. It is recommended to enhanced coordination between ex situ and in situ conservation stakeholders for sustaining the long term conservation of CWR in Indonesia. Implementation of the research recommendations will provide for the first time an effective conservation planning of Indonesia’s CWR diversity and will significantly enhance the country’s food and nutritional security.

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2.
Plant conservation urgently needs a concept that would unify different aspects of population viability as parts of conservation methodology. Such unification is especially lacking for ex situ conservation. We introduce a novel conservation approach in which ex situ collections maintained in natural or semi-natural environment and preserving both neutral and adaptive genetic diversity are a part of a complementary ex situ–in situ conservation strategy. Our approach is the first that explicitly takes into account ecologically significant (i.e. adaptive) variation of plants in both ex situ and in situ conservation actions. Using this approach we provide detailed guidelines for (1) representative sampling of the populations; (2) collection maintenance; and (3) utilization for in situ actions.  相似文献   

3.
Ex situ seed banking is a practical and cost-effective means of preserving wild plant diversity and a crucial complement to the in situ conservation and restoration of species and habitats. As pressures on the natural environment have grown, so has the call for seed banks to provide scientifically-robust,practical solutions to seed-related problems in nature conservation, from single-species recovery and reintroduction to the restoration of complex, dynamic communities at the largest scales. In this paper, we discuss how the Royal Botanic Gardens, Kew and its Millennium Seed Bank have responded to this call in the United Kingdom. We demonstrate that banked seed collections can provide a range of otherwiseunavailable, high quality, known-origin, genetically-diverse biological materials. The data, expertise and specialist facilities that accompany these collections are also valuable, helping overcome constraints to the collection, production and effective use of native seed. Challenges remain-to ensure ex situ collections protect the species and genetic diversity that will enable plants to adapt to a changing environment, and to find new ways for seed banks to mobilise their resources at a landscape scale.  相似文献   

4.
The genetic diversity of endemic Madagascan Coffea species has not received any considerable attention, despite the high extinction threat facing most of the species on the island. In order to address this shortfall, we assessed and compared the genetic diversity and allelic richness of ex situ and in situ populations for four selected species, and 18 ex situ populations maintained at the Kianjavato Coffee Research Station. We also investigated the possibility of in situ and ex situ hybridization events for Madagascan coffee, both within and between species. For these purposes, we used 18 nuclear microsatellite markers, on a total of 37 Coffea populations (4 in situ and 33 ex situ) representing a total of 398 genotypes (96 in situ and 302 ex situ) for 23 species. Our study showed (1) strong differentiation between Madagascan Coffea species; (2) good differentiation between all the populations studied, including those from the same locality (even when the area of the locality was restricted); (3) good evidence for both in situ and ex situ hybridization, although in situ hybridization appeared to be limited; (4) much higher genetic diversity within in situ collections compared to ex situ collections; and (5) that, despite limitations, the Kianjavato Coffee Research Station collection is an extremely valuable resource of Madagascan coffee germplasm. Recommendations for in situ and ex situ germplasm conservation are discussed.  相似文献   

5.
Plant genetic resource conservation strategies, informed by an understanding of the geographical distribution of genetic variation within species, are likely to result in a wider representation of conserved diversity in ex situ gene banks and in situ genetic reserves. The main objective of this study was to map the geographical distribution of genetic variation, as revealed by randomly amplified polymorphic DNA (RAPDs), in four wild relatives of the cultivated lentil, namely Lens culinaris ssp. orientalis, L. odemensis, L. ervoides and L. nigricans . Areas of high diversity and unique diversity were located for each taxon, and regions where further germplasm collection was most likely to yield novel genetic variation were identified. There were centres of diversity for L. culinaris ssp. orientalis in southeast Turkey and northwest Syria, and in south Syria and Jordan. A centre of diversity was found to exist in Sweida province, south Syria, for L. odemensis , and for L. ervoides along the coastal border region between Syria and Turkey stretching down along the Syrian coast. There was a centre of diversity for L. nigricans in west Turkey. Analytical techniques previously used at the species level were found to be useful at the genotypic level to objectively target areas for future collection missions, to increase diversity in ex situ collections and to target areas for in situ conservation.  相似文献   

6.
Ex situ germ plasm collections of woody crops are necessary to ensure the optimal use of plant genetic resources. The fig tree (Ficus carica L.) germ plasm bank, consisting of 229 accessions, is located in Centro de Investigación ‘La Orden’. Despite great progress in conservation, ex situ collections face size and organization problems. Core collections obtained from structured samples of bigger collections are a useful tool to improve germ plasm management. In this work, we used simple sequence repeat (SSR) markers to establish a core collection in this underutilised Mediterranean fruit tree species. Four approaches have been carried out (random sampling, maximization, simulated annealing and stepwise clustering) to determine the best method to develop a core collection in this woody plant. The genetic diversity obtained with each subset was compared with that of the complete collection. It was found that the most efficient way to achieve the maximum diversity was the maximization strategy, which, with 30 accessions, recovers all the SSR alleles and does not show significant differences in allele frequency distribution in any of the loci or in the variability parameters (H O, H E) between the whole and core collections. Thus, this core collection, a representative of most fig diversity conserved in the germ plasm bank, could be used as a basis for plant material exchange among researchers and breeders.  相似文献   

7.
8.
Increasing germplasm erosion requires the recovery and conservation of traditional cultivars before they disappear. Here we present a particular case in Spain where a thorough prospection of local fruit tree species was performed in the 1950s with detailed data of the origin of each genotype but, unfortunately, the accessions are no longer conserved in ex situ germplasm collections. However, for most of those cultivars, an old stone collection is still preserved. In order to analyze the diversity present at the time when the prospection was made and to which extent variability has been eroded, we developed a protocol in apricot (Prunus armeniaca L.) to obtain DNA from maternal tissues of the stones of a sufficient quality to be amplified by PCR. The results obtained have been compared with the results from the profiles developed from apricot cultivars currently conserved in ex situ germplasm collections. The results highlight the fact that most of the old accessions are not conserved ex situ but provide a tool to prioritize the recovery of particular cultivars. The approach used in this work can also be applied to other plant species where seeds have been preserved.  相似文献   

9.
Dendrobium officinale (Orchidaceae) is an endangered plant species with important medicinal value. To evaluate the effectiveness of ex situ collection of D. officinale genetic diversity, we developed 15 polymorphic trinucleotide microsatellite loci of D. officinale to examine the genetic diversity and structure of three D. officinale germplasm collections comprising 120 individuals from its germplasm collection base and their respective wild populations consisting of 62 individuals from three provinces in China. The three germplasm collections showed reductions in gene diversity and average number of alleles per locus, but an increase in average number of rare alleles (frequency?≤?0.05) per locus in comparison to their wild populations. However, the differences in gene diversity between the germplasm collections and wild populations were not statistically significant. The analysis using STRUCTURE revealed evident differences in genetic composition between each germplasm collection and its wild population, probably because the D. officinale individuals with distinct genotypes in each wild population were unevenly selected for establishing its germplasm collection. For conservation management plans, we propose that D. officinale individuals with rare alleles need to be conserved with top priority, and those individuals with the most common alleles also should be concerned. The 15 new microsatellite loci may be used as a powerful tool for further evaluation and conservation of the genetic diversity of D. officinale germplasm resources.  相似文献   

10.
Cacao (Theobroma cacao L.), the tree from which cocoa butter and chocolate is derived, is conserved in field genebanks. The largest of these ex situ collections in the public domain is the International Cocoa Genebank, Trinidad (ICG,T). Reduction of genetic redundancy is essential to improve the accuracy and efficiency of genebank management. This study examined the pedigree and genetic diversity in a subset of 387 accessions in this collection. Sibship reconstruction of this subset revealed 56 full-sib families nested within 189 half-sib families. Sixteen centers of interconnectivity were identified, which suggested a high level of genetic redundancy in the collection. Generally, consistent phylogenetic trees were obtained using different genetic distance measures. However, a principal coordinate analysis of the D est differentiation measure elicited the best representation of accession group clustering, and we recommend this approach when probing fine-scale genetic differentiation among cacao accessions. The composite genetic diversity of 414 cacao accessions was contained in a core set of 59 unique accessions. These results have significant implications in the conservation of genetic resources of the ICG,T and other cacao genebanks. The approach developed in this study is recommended as a strategy to curators in guiding conservation management practices of cacao and other similar ex situ genebanks.  相似文献   

11.
Botanic gardens and arboreta, particularly in regions where iconic relict trees naturally occur, play a vital role in the conservation of these species. Maintaining well-managed living ex situ collections of rare and threatened relict tree species provides an immediate insurance policy for the future species conservation. The aim of this research was to investigate the origin, representativeness and genetic diversity of relict trees kept in botanic gardens and arboreta. We used as a model two ecologically and biogeographically distinct members of the prominent relict genus Zelkova (Ulmaceae), which survived the last glaciation in disjunct and isolated refugial regions: Z. carpinifolia in Transcaucasia and Z. abelicea endemic to Crete (Greece) in the Mediterranean. Our study revealed substantial differences in the genetic diversity and the origin of living ex situ collections of the two investigated taxa. The living ex situ collections of Z. carpinifolia have relatively high representativeness compared with the global genetic variability of natural stands identified in a previous study. In contrast, Z. abelicea, which possesses an extraordinarily high genetic variability in natural populations, is clearly underrepresented in botanic garden collections. Moreover, all Z. abelicea trees investigated in this study most probably originated from a single region, the Levka Ori in western Crete. Thus, the ex situ conservation of Z. abelicea requires major planning and coordination efforts, including the establishment of well-documented collections in botanic gardens in Greece and especially on Crete. New living ex situ collections should be created using plant material collected from all of the mountain regions where Z. abelicea still occurs. Our study highlights the need for re-evaluating the existing living ex situ collections of trees and the development of new strategies for future conservation efforts in botanic gardens and arboreta. The coordination of conservation efforts between gardens must be enhanced to prioritize actions for the most threatened relict tree species.  相似文献   

12.
Many of Chile’s iconic cactus species are threatened by human activities and global change. In order to safeguard them from extinction, both in situ and ex situ conservation actions are urgently needed. In this paper, an overview is given of the in situ and ex situ conservation status of the mainly Chilean cactus genera Copiapoa, Eriosyce and Eulychnia, including a worldwide survey of living ex situ collections of the species of these genera. From our results, we can conclude that although the threats to Chile’s remarkable biodiversity are now recognized as an environmental problem, and efforts are underway to protect the threatened endemic flora, many of the most threatened species are currently not protected in situ. Although a higher percentage of living accessions of Copiapoa, Eriosyce and Eulychnia in ex situ collections are of known wild origin compared to results of previous studies on other plant groups, the number of available accessions is insufficient to adequately preserve the genetic diversity of the threatened species. Prospects to upscale both in situ and ex situ conservation of the studied genera are discussed.  相似文献   

13.
There is a growing call for inventories that evaluate geographic patterns in diversity of plant genetic resources maintained on farm and in species' natural populations in order to enhance their use and conservation. Such evaluations are relevant for useful tropical and subtropical tree species, as many of these species are still undomesticated, or in incipient stages of domestication and local populations can offer yet-unknown traits of high value to further domestication. For many outcrossing species, such as most trees, inbreeding depression can be an issue, and genetic diversity is important to sustain local production. Diversity is also crucial for species to adapt to environmental changes. This paper explores the possibilities of incorporating molecular marker data into Geographic Information Systems (GIS) to allow visualization and better understanding of spatial patterns of genetic diversity as a key input to optimize conservation and use of plant genetic resources, based on a case study of cherimoya (Annona cherimola Mill.), a Neotropical fruit tree species. We present spatial analyses to (1) improve the understanding of spatial distribution of genetic diversity of cherimoya natural stands and cultivated trees in Ecuador, Bolivia and Peru based on microsatellite molecular markers (SSRs); and (2) formulate optimal conservation strategies by revealing priority areas for in situ conservation, and identifying existing diversity gaps in ex situ collections. We found high levels of allelic richness, locally common alleles and expected heterozygosity in cherimoya's putative centre of origin, southern Ecuador and northern Peru, whereas levels of diversity in southern Peru and especially in Bolivia were significantly lower. The application of GIS on a large microsatellite dataset allows a more detailed prioritization of areas for in situ conservation and targeted collection across the Andean distribution range of cherimoya than previous studies could do, i.e. at province and department level in Ecuador and Peru, respectively.  相似文献   

14.
The use of in vitro techniques for conservation has been rising steadily since their inclusion in The Convention on Biological Diversity and The Global Strategy for Plant Conservation. Unfortunately, bryophytes are often overlooked in conservation initiatives, but they are important in a number of large-scale ecosystem processes, i.e. nutrient, water and carbon cycling. There is a long history of the use of tissue culture in cultivating bryophytes, and many species respond well to in vitro techniques. For 6 yr (2000–2006), The Royal Botanic Gardens, Kew and the UK statutory conservation agencies supported a project for the ex situ conservation of bryophytes. Living and cryopreserved collections of UK threatened species were successfully established and the cryopreserved collection continues to be maintained. Other in vitro conservation collections are maintained over Europe, at botanic gardens, museums and by individual university researchers, but there is no coherent European collection of bryophytes for conservation, or standardisation of techniques. A major issue for many in vitro collections is the maintenance of within species genetic diversity. Such diversity is considered to be important, as it is the basis by which populations of species can adapt to new conditions and evolve. We are proposing to establish a European network for in vitro conservation of bryophytes. We envisage that this will include living collections, cryopreserved collections and spore collections. Conservation of genetic diversity would be a priority and the collections would provide a valuable resource for conservation initiatives and support research into rare and threatened species.  相似文献   

15.
Thousands of years ago humans began domesticating crops as a food source. Among the wild germplasm available, they selected those that were best adapted for cultivation and utilization. Although wild ancestors have continued to persist in regions where domestication took place, there is a permanent risk of loss of the genetic variability of cultivated plants and their wild relatives in response to changing environmental conditions and cultural practices. Recognizing this danger, plant ex situ genebank collections were created since the beginning of the last century. World-wide, more than 6 million accessions have been accumulated including the German ex situ genebank in Gatersleben, one of the four largest global collections, housing 150,000 accessions belonging to 890 genera and 3032 species. This review summarizes the ex situ plant genetic resources conservation behavior with a special emphasis on German activities. Strategies for maintenance and management of germplasm collections are reviewed, considering modern biotechnologies (in vitro and cryo preservation). General aspects on genetic diversity and integrity are discussed.  相似文献   

16.
Smallholders’ agroforests may be valuable for conserving tropical trees through three main mechanisms. First, trees planted and/or retained by farmers in agricultural landscapes where wild stands were once found may be circa situm reservoirs of biodiversity. Second, farmland trees may support conservation in situ by providing an alternative source of product to reduce extraction from forest, and by acting as ‘corridors’ or ‘stepping stones’ that connect fragmented wild stands. Third, the additional value that planting assigns to trees may result in greater interest in including them in seed collections, field trials and field ‘genebanks’ that support ex situ conservation. Here, we critically review the evidence for these mechanisms, and highlight areas for research and for intervention so that agroforestry practices can better support conservation in each setting, with an emphasis on often neglected genetic-level considerations. Based on current global challenges to diversity, conservation will need to rely increasingly on a smallholder-farm circa situm approach, but concerns on long-term effectiveness need to be properly quantified and addressed. Connectivity between widely dispersed, low density trees in agricultural landscapes is an important factor determining the success of the circa situm approach, while improving farmers’ access to a diversity of tree germplasm that they are interested in planting is required. The circumstances in which agroforestry plantings can support in situ conservation need to be better defined, and research on the stability of active tree seed collections (how long are species and populations retained in them?) as ex situ reservoirs of biodiversity is needed.  相似文献   

17.
The Puerto Rican Boa (Chilabothrus inornatus) was placed on the US Endangered Species List in 1970. Progress has been made since to clarify the recovery status of this species, though the design of a new recovery plan must include information regarding genetic variation within and among populations of this species. While measures of genetic diversity in wild populations of this species are finally becoming available, relative genetic diversity represented in ex situ populations is unknown, which hampers efforts to develop an ex situ species management plan. Here, we provide an analysis of genetic diversity in US public and private collections (zoos and breeders) using mitochondrial sequence data and five highly polymorphic nuclear microsatellite loci. We analyzed 50 boas from the US ex situ population and determined overall genetic diversity and relatedness among these individuals. We then compared these data to mitochondrial and microsatellite data obtained from 176 individuals from wild populations across the native range of the species. We found little inbreeding and a large amount of retained genetic diversity in the US ex situ population of C. inornatus relative to wild populations. Genetic diversity in the ex situ population is similar to that found in wild populations. Ours is only the second explicit attempt to characterize genetic diversity at the molecular level in ex situ populations of boid snakes. We anticipate that these results will inform current breeding strategies as well as offer additional information that will facilitate the continuation of ex situ conservation breeding or management in boas.  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.
Ex situ germplasm collections seek to conserve maximum genetic diversity in a small number of samples. Geographic and environmental information have long been treated as surrogate measures of genetic diversity, proposed to be useful for increasing allelic diversity of collections. We examine the effect of maximizing geographic and environmental diversity on the retention of distinct haplotype blocks in germplasm subsets, using three species with extensive genomewide genotypic data. We show that maximizing diversity in the surrogate measures produces subsets with uneven representation of haplotypic diversity across the genome. Some regions are well-conserved, exhibiting high haplotypic diversity, while others are poorly-conserved and contain significantly less haplotypic diversity than would be obtained via random sampling. In two of three species, poorly-conserved genomic regions were enriched in regulatory genes which, as a class, contribute to phenotypic variation. The specific genes affected varied by species but, overall, haplotypic diversity was poorly-conserved at genes controlling?~?10% of major molecular functions and biological processes. While this study was limited to three exemplar species, we find little evidence to support continued use of geographic or environmental surrogates for ex situ conservation activities attempting to capture maximum genomewide allelic diversity. Although geographic and environmental diversity have proven to be reliable predictors of allele frequency differences and ecotypic differentiation across species ranges, they appear to be poor predictors of allelic diversity per se, offering little opportunity to enrich collections for haplotypic diversity overall, and ample opportunity to bias the conservation of important functional genetic variation. We propose a bioinformatic bridge between haplotypic diversity and the potential phenotypic diversity residing in collections using the Gene Ontology.  相似文献   

20.
Dehaasia pugerensis Koord. & Valeton is a threatened Indonesian Lauraceae species. It is an endemic tree known only from Jember Regency in East Java. To enhance the conservation of D. pugerensis, we conducted a population survey in several locations in Jember where the species were previously collected. The objectives were to: i) assess the current population status of D. pugerensis, ii) collect plant materials (seed, seedling, or cutting) to serve as ex situ collections, and iii) update the conservation status of the species according to IUCN Red List Category and Criteria. We only found D. pugerensis in 6 out of 16 locations in Wuluhan and Ambulu District during the survey. We successfully located 560 individuals of the species, of which 194 individuals (34.6%) were in the mature stage. Based on the diameter and height classes, the population of D. pugerensis formed a reverse J-shaped size distribution. We successfully collected 23 seeds and 15 seedlings of the species for ex situ collections. Our findings showed that the current status of D. pugerensis is Critically Endangered (CR) based on criteria B1ab(i,ii,iii,iv,v)and C2a(ii). Under these categories, the species faces an extremely high risk of extinction in the wild. Therefore, prompt comprehensive conservation actions are needed to ensure the survival of the species.  相似文献   

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