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1.
About a quarter of Chinese wild orchid species are used in traditional medicine or as health food supplements. The market demand for some species, such as those in the epiphytic genus Dendrobium, has diminished many wild populations to local extinction or dangerously small numbers. Conservation of these heavily exploited orchids currently relies on a two-pronged approach: establishing nature reserves and encouraging massive commercial cultivation in artificial settings. We argue that these measures are not sufficient to restore or maintain healthy wild populations, and augmentation and reintroduction of these species in natural forests are needed. We argue for an unconventional reintroduction approach, in which populations planted in natural forests are allowed to be sustainably harvested (restoration-friendly cultivation). Because Dendrobium orchids are epiphytic, restoration-friendly cultivation of these species will not be at the expenses of other native plants. In addition, market premiums on wild-collected medicinal plants will generate incentives for farmers who participate in restoration-friendly cultivation to preserve natural forests. With proper policy and oversight, the restoration-friendly cultivation of medicinal Dendrobium orchids will facilitate the conservation of these threatened species, encourage protection of natural forests, and benefit marginalized rural communities. Adding this restoration-friendly cultivation into the current mix of conservation approaches has the potential to turn deeply-entrenched traditional uses of orchids from a conservation challenge to a conservation success.  相似文献   

2.
Crop wild relatives possess important traits, therefore ex situ and in situ conservation efforts are essential to maintain sufficient options for crop improvement. Bolivia is a centre of wild relative diversity for several crops, among them potato, which is an important staple worldwide and the principal food crop in this country. Despite their relevance for plant breeding, limited knowledge exists about their in situ conservation status. We used Geographic Information Systems (GIS) and distribution modelling with the software Maxent to better understand geographic patterns of endemic wild potato diversity in Bolivia. In combination with threat layers, we assessed the conservation status of all endemic species, 21 in total. We prioritised areas for in situ conservation by using complementary reserve selection and excluded 25% of the most-threatened collection sites because costs to implement conservation measures at those locations may be too high compared to other areas. Some 70% (15 of 21 species) has a preliminary vulnerable status or worse according to IUCN red list distribution criteria. Our results show that four of these species would require special conservation attention because they were only observed in <15 locations and are highly threatened by human accessibility, fires and livestock pressure. Although highest species richness occurs in south-central Bolivia, in the departments Santa Cruz and Chuquisaca, the first priority area for in situ conservation according to our reserve selection exercise is central Bolivia, Cochabamba; this area is less threatened than the potato wild relatives’ hotspot in south-central Bolivia. Only seven of the 21 species were observed in protected areas. To improve coverage of potato wild relatives’ distribution by protected areas, we recommend starting inventories in parks and reserves with high modelled diversity. Finally, to improve ex situ conservation, we targeted areas for germplasm collection of species with <5 accessions conserved in genebanks.  相似文献   

3.
Picrorhiza kurrooa, one of the important plant species among the various medicinal plants, is endemic to Himalaya. As the plant is useful in the treatment of various diseases, e.g., hepatic disorders, gastric troubles, anemia, asthma, etc., illegal collection from the wild is increasing and now this plant is banned for export in any form and listed as ‘endangered’. Ecological studies carried out on this species in last few decades suggested that the availability of this species in its specific habitats is comparatively lower than other associate species. Possible factors responsible for this depletion are increasing demand in the pharmaceutical industries, habitat specificity, heavy exploitation from the wild, unorganized cultivation practices etc. Biotechnology is playing a crucial role to conserve this important plant species. The past 23 years have witnessed a progressive biotechnological advances made in P. kurrooa. People have published various reports on establishments of in vitro culture techniques including micropropagation, synthetic seed production, plant regeneration via callus-mediated shoot organogenesis, adventitious shoot regeneration, genetic transformation through Agrobacterium rhizogenes, secondary metabolite analysis etc. This review attempts to focus on present ecological status and provide a comprehensive account on the tissue culture-mediated biotechnological interventions made in P. kurrooa for improvement and conservation of this medicinally important plant.  相似文献   

4.
As biodiversity declines, wildlife conservation focuses on in situ and ex situ management strategies. Zoo-based breeding programmes are often designed to contribute to the conservation of species that are threatened in the wild. Diet contributes to the reproductive success, disease status and longevity of all animals. It is near-impossible to replicate a species' diet in captivity using only the species they consume in the wild, but the nutritional composition of a wild diet, if known, can be closely matched using commercially available foods for which the nutritional composition has been calculated. Ecological research has identified food items of importance in the diet of many species. However, the nutritional composition of these food items is rarely evaluated, even though the composition of wild food items is important in understanding the dietary adaptations and requirements of wildlife. In contrast, the nutritional requirements of domestic species are well researched and can be used to predict a range of plausible nutrient requirements of some wild species, especially those with similar life histories. Access to wild populations provides further opportunities for nutritional science to determine the requirements of individual species. Small-scale dietary experimentation undertaken at conservation institutions may show positive effects on health and welfare but is rarely published in the scientific literature. This review describes current standards in nutritional management of birds and recommends pathways for filling knowledge gaps. Research on mammals has dominated the nutrition literature, so there is a relative lack of nutritional management information for birds. We combine concepts of domestic animal nutrition with recent findings on the nutritional requirements of birds to provide a foundation for further studies of avian nutrition. We call for the broader zoological community to share data and collaborate on nutritional research to support conservation institutions in nutritional management of wild birds.  相似文献   

5.
Many amphibians have declined globally due to introduction of the pathogenic fungus Batrachochytrium dendrobatidis (Bd). Hundreds of species, many in well-protected habitats, remain as small populations at risk of extinction. Currently the only proven conservation strategy is to maintain species in captivity to be reintroduced at a later date. However, methods to abate the disease in the wild are urgently needed so that reintroduced and wild animals can survive in the presence of Bd. Vaccination has been widely suggested as a potential strategy to improve survival. We used captive-bred offspring of critically endangered booroolong frogs (Litoria booroolongensis) to test if vaccination in the form of prior infection improves survival following re exposure. We infected frogs with a local Bd isolate, cleared infection after 30 days (d) using itraconazole just prior to the onset of clinical signs, and then re-exposed animals to Bd at 110 d. We found prior exposure had no effect on survival or infection intensities, clearly showing that real infections do not stimulate a protective adaptive immune response in this species. This result supports recent studies suggesting Bd may evade or suppress host immune functions. Our results suggest vaccination is unlikely to be useful in mitigating chytridiomycosis. However, survival of some individuals from all experimental groups indicates existence of protective innate immunity. Understanding and promoting this innate resistance holds potential for enabling species recovery.  相似文献   

6.
The inter-Andean tropical rainforests and dry forests of the Magdalena river basin (Tumbes-Choco-Magdalena biodiversity hotspot) in northern Colombia have undergone significant forest loss and degradation in recent decades. Six primate species inhabit this region, five of which are currently threatened with extinction and one of which—the brown spider monkey, Ateles hybridus—is considered critically endangered. Accurate and recent information on the distribution and conservation status of these threatened primate populations is scarce or nonexistent, even though such data are needed to implement successful conservation actions and management plans. Between 2006 and 2016, we evaluated the status and distribution of primates across inter-Andean lowland forests in northern Colombia. We visited 30 sites to evaluate the presence/absence of brown spider monkeys and other primate taxa in the region. We also carried out surveys at 10 of these sites to obtain estimates of primate population densities and demographic information from forests with different levels of anthropogenic disturbance. Novel data on primate presence/absence were obtained for 27 sites, and 136 records were collected in total. Only 33% of the sites visited were large forest fragments (>?500 Ha). This study confirms that at least six primate species are still present in the Rio Magdalena region, which represents the highest platyrrhine diversity west of the Andes. This study also confirms the persistence of a wild population of Colombian woolly monkeys (Lagothrix lagotricha lugens) in the Serranía de San Lucas. Assigning formal protected status to this region is an urgent priority for the conservation of primates in the Rio Magdalena region.  相似文献   

7.
The newly discovered endemic maple Acer yangbiense of China has only five individuals left in the wild, and thus has been classified as a plant species with extremely small populations (PSESP). PSESP species call for emergency protection procedures, such as ex-situ conservation and reintroduction. Our objectives were to examine the genetic diversity of A. yangbiense and to evaluate former conservation strategies from a genetic point of view. Our results suggested that A. yangbiense was not genetically depauperate, but its genetic loss at a species level was obvious. A parentage analysis indicated a high selfing-rate in A. yangbiense and suggested the existence of a previously unknown wild individual. Former conservation strategies did not include all genetic variations of the wild population, and gene diversity of the ex-situ conserved seedlings is lower than that of the wild population. From our findings, we make suggestions to guide the subsequent protection of this species.  相似文献   

8.
A role for molecular genetic approaches in conservation of endangered taxa is now commonly recognized. Because conservation genetic analyses provide essential insights on taxonomic status, recent evolutionary history and current health of endangered taxa, they are considered in nearly all conservation programs. Genetic analyses of the critically endangered Far Eastern, or Amur leopard, Panthera pardus orientalis, have been done recently to address all of these questions and develop strategies for survival of the leopard in the wild. The genetic status and implication for conservation management of the Far Eastern leopard subspecies are discussed.  相似文献   

9.
The Ethnobotany and Ethnopharmacology of Wild Tomatillos, Physalis longifolia Nutt., and Related Physalis Species: A Review. The wild tomatillo, Physalis longifolia Nutt., and related species have been important wild-harvested foods and medicinal plants. This paper reviews their traditional use as food and medicine; it also discusses taxonomic difficulties and provides information on recent medicinal chemistry discoveries within this and related species. Subtle morphological differences recognized by taxonomists to distinguish this species from closely related taxa can be confusing to botanists and ethnobotanists, and many of these differences are not considered to be important by indigenous people. Therefore, the food and medicinal uses reported here include information for P. longifolia, as well as uses for several related taxa found north of Mexico. The importance of wild Physalis species as food is reported by many tribes, and its long history of use is evidenced by frequent discovery in archaeological sites. These plants may have been cultivated, or ??tended,?? by Pueblo farmers and other tribes. The importance of this plant as medicine is made evident through its historical ethnobotanical use, information in recent literature on Physalis species pharmacology, and our Native Medicinal Plant Research Program??s recent discovery of 14 new natural products, some of which have potent anti-cancer activity.  相似文献   

10.
More than 3,000 species are listed as critically endangered worldwide, and various conservation measures such as habitat restoration, assisted reproduction and establishment of ex situ populations would be required to prevent their extinction. We determined the genotype of all 15 known wild clumps using nuclear microsatellite markers for Stachyurus macrocarpus var. prunifolius, a critically endangered shrub endemic to the Ogasawara (Bonin) Islands of Japan. In addition, the seedlings propagated from seeds taken from one wild clumps were genotyped. The results of complete genotyping showed that both wild and nursery populations had population-specific alleles. Two alleles were detected only in the nursery population, indicating the existence of undiscovered mature individuals in the wild. Four alleles were found only in the wild and were detected in two geographically isolated clumps, and this finding may propose that re-introduction and transplantation between different sites requires sensitive handling in terms of the conservation of evolutionary significant units. These results show that complete genotyping can provide essential genetic and ecological information for effective management of endangered species.  相似文献   

11.
The palm species Pseudophoenix ekmanii (endemic to the Dominican Republic) and P. lediniana (endemic to Haiti) are the only Critically Endangered species (sensu IUCN) of the genus. Results are presented of recent field research and population genetic studies targeting P. lediniana. The field research confirmed that wild plants of P. lediniana are restricted to a single population found along almost inaccessible and unstable limestone cliffs along a ravine in southern Haiti, near Jacmel in the Province of Ouest. The population is composed of six fragments with approximately 71 adults and 2 juveniles. No seedlings were located, and the population is under severe extinction threat because of landslides during the raining season, massive forest clearance, and burns for charcoal extraction and cropping of subsistence staple crops. Seven DNA microsatellite (SSR) loci were used to generate estimates of genetic variation of this species. Approximately one-third of all wild plants (21 individuals) were sampled. Only four of these SSR loci were polymorphic and population genetic coefficients showed that the population is highly inbred. Population genetics results for P. lediniana were compared with those previously published for P. ekmanii. Levels of genetic variation were quantified by number of polymorphic loci and observed heterozygosity. These values were much lower in P. ledinana than in P. ekmanii. The latter species is officially protected in a national park and has several populations, some much larger than that of the P. lediniana population. Differences concerning in situ conservation protection and population size might explain differences for levels of genetic variation between these two Critically Endangered species. Ex situ and in situ strategies for conservation are proposed.  相似文献   

12.
Investigating crop origins is a priority to understand the evolution of plants under domestication, develop strategies for conservation and valorization of agrobiodiversity and acquire fundamental knowledge for cultivar improvement. The date palm (Phoenix dactylifera L.) belongs to the genus Phoenix, which comprises 14 species morphologically very close, sometimes hardly distinguishable. It has been cultivated for millennia in the Middle East and in North Africa and constitutes the keystone of oasis agriculture. Yet, its origins remain poorly understood as no wild populations are identified. Uncultivated populations have been described but they might represent feral, i.e. formerly cultivated, abandoned forms rather than truly wild populations. In this context, this study based on morphometrics applied to 1625 Phoenix seeds aims to (1) differentiate Phoenix species and (2) depict the domestication syndrome observed in cultivated date palm seeds using other Phoenix species as a “wild” reference. This will help discriminate truly wild from feral forms, thus providing new insights into the evolutionary history of this species. Seed size was evaluated using four parameters: length, width, thickness and dorsal view surface. Seed shape was quantified using outline analyses based on the Elliptic Fourier Transform method. The size and shape of seeds allowed an accurate differentiation of Phoenix species. The cultivated date palm shows distinctive size and shape features, compared to other Phoenix species: seeds are longer and elongated. This morphological shift may be interpreted as a domestication syndrome, resulting from the long-term history of cultivation, selection and human-mediated dispersion. Based on seed attributes, some uncultivated date palms from Oman may be identified as wild. This opens new prospects regarding the possible existence and characterization of relict wild populations and consequently for the understanding of the date palm origins. Finally, we here describe a pipeline for the identification of the domestication syndrome in seeds that could be used in other crops.  相似文献   

13.
The increasing fragmentation of forest habitats and the omnipresence of cultivars potentially threaten the genetic integrity of the European wild apple (Malus sylvestris (L.) Mill). However, the conservation status of this species remains unclear in Europe, other than in Belgium and the Czech Republic, where it has been declared an endangered species. The population density of M. sylvestris is higher in the forests of the upper Rhine Valley (France) than in most European forests, with an unbalanced age-structure, an overrepresentation of adults and a tendency to clump. We characterize here the ecology, age-structure and genetic diversity of wild apple populations in the Rhine Valley. We use these data to highlight links to the history of this species and to propose guidelines for future conservation strategies. In total, 255 individual wild apple trees from six forest stands (five floodplain forests and one forest growing in drier conditions) were analysed in the field, collected and genotyped on the basis of data for 15 microsatellite markers. Genetic analyses showed no escaped cultivars and few hybrids with the cultivated apple. Excluding the hybrids, the genetically “pure” populations displayed high levels of genetic diversity and a weak population structure. Age-structure and ecology studies of wild apple populations identified four categories that were not randomly distributed across the forests, reflecting the history of the Rhine forest over the last century. The Rhine wild apple populations, with their ecological strategies, high genetic diversity, and weak traces of crop-to-wild gene flow associated with the history of these floodplain forests, constitute candidate populations for inclusion in future conservation programmes for European wild apple.  相似文献   

14.
We use chloroplast DNA sequencing to examine aspects of the pre-European Māori cultivation of an endemic New Zealand root crop, Arthropodium cirratum (rengarenga). Researching the early stages of domestication is not possible for the majority of crops, because their cultivation began many thousands of years ago and/or they have been substantially altered by modern breeding methods. We found high levels of genetic variation and structuring characterised the natural distribution of A. cirratum, while the translocated populations only retained low levels of this diversity, indicating a strong bottleneck even at the early stages of this species’ cultivation. The high structuring detected at four chloroplast loci within the natural A. cirratum range enabled the putative source(s) of the translocated populations to be identified as most likely located in the eastern Bay of Plenty/East Cape region. The high structuring within A. cirratum also has implications for the conservation of genetic diversity within this species, which has undergone recent declines in both its natural and translocated ranges.  相似文献   

15.
Establishing new populations is essential for preventing the extinction of critically endangered plant species. However, defining the range of environmental conditions suitable for the most severely endangered species is challenging, since few wild populations remain for study. Experimental reintroductions of these species can achieve multiple conservation goals by improving our understanding of habitat and management requirements while simultaneously establishing new populations. We demonstrate this with Arenaria paludicola, a critically endangered wetland plant species now known from a single wild population in coastal California. Before transplanting, we tested salinity tolerance in the greenhouse, and found tolerance of a broader range of soils than expected based on the current distribution. We then transplanted A. paludicola in three different habitat types, with and without neighbor removal. Success of A. paludicola transplants differed dramatically between the three habitat types, indicating the importance of variation at the habitat and microhabitat level. The best practices for transplant management are context-dependent: neighbor removal may promote the growth of A. paludicola, but neighbors may also facilitate transplant establishment in unstable substrates. After one year, A. paludicola continued to thrive in habitats dominated by Oenanthe sarmentosa with open canopies and moist soil. This habitat differs from that of the remaining wild population. Our discovery of an additional habitat type suitable for A. paludicola will allow more effective selection of future transplant sites.  相似文献   

16.

Background

Wild plant gathering is an essential element in livelihood strategies all over the world. However due to changing circumstances in Europe, the reason for gathering has altered from one of necessity in the past to a pleasurable activity today. Wild plant gathering has therefore also received renewed attention as a form of intangible cultural heritage expressing local preferences, habits and man??s relationship with nature. In the Biosphere Reserve Grosses Walsertal (Austria), local people??s knowledge of the gathering of wild plants and their perception of their own gathering activities are being documented. The focus of this paper is on the uses of herbal teas and the informal guidelines for gathering plants that have been issued by the Bergtee (mountain tea) association.

Methods

Thirty-six free-list interviews were conducted with subsequent semi-structured interviews and three focus group meetings held with members of the Bergtee association. Participatory observation (gathering and processing plants, mixing and marketing tea) also allowed for greater understanding of what had been reported.

Results

In total, 140 different gathered plant species were listed by respondents. Herbal tea is the most frequently mentioned use. The Bergtee association, founded by a young man and two middle-aged women in the valley, is a good example of the link between biological and cultural diversity, with the aim of sharing the biosphere reserve??s natural treasures as well as local plant-related knowledge in the form of herbal tea products. The association??s informal guidelines for gathering reflect people??s attitude to nature: monetary income does not play a major role in gathering plants; instead people??s appreciation of the value of the nature around them is to the fore.

Conclusions

Gathering wild plants can be seen as an expression of people??s regional identity. The conscious appreciation of nature and related local knowledge is crucial for the sustainable conservation and use of the Biosphere Reserve??s resources.  相似文献   

17.
The Rhododendron of China exhibit great diversity, however no conservation evaluation of the genus had been performed, as a result of no governmental financial support. Based on our recent field investigations covering a total of seven provinces and 95 days from 2011 to 2013 in China, we herein provide an updated conservation status on eight species plus two further species that are listed as endangered and vulnerable in the Red List of Rhododendrons in which the evaluation was mainly based on old records. Our surveys indicated that urgent conservation actions to the two critically endangered species R. magniflorum (less than 10 extant plants) and R. roxieoides (only 22 mature individuals) should be performed. Moreover, we proposed that species represented by few plants, and that grow at low altitude, in disturbed habitats, should be given priority for ex- and in-situ conservation. Despite current distributions of all listed endangered Rhododendrons were not fully covered, our report aimed to arouse conservation attention and actions on Rhododendrons preferably by governmental financial support in China.  相似文献   

18.
Euptelea pleiospermum is an ??old rare?? tree species distributed along the high-elevation streamsides in Burma, China, and India. Deforestation and construction of roads for timber transport have highly fragmented the natural habitats of this species in the Shennongjia Forestry District. In this study, we used this fragmentation to test the hypothesis that ??old rare?? tree species are insusceptible to the genetic consequences of habitat fragmentation. Using eight microsatellite loci, we estimated allelic richness (A R), observed heterozygosity (H O), expected heterozygosity (H E), Wright??s inbreeding coefficient (F IS), and genetic differentiation (F ST and D EST) between pre- and post-fragmentation cohorts. We found no significant differences in either genetic diversity or genetic differentiation between the two cohorts. The limited genetic effects of fragmentation may result from too few fragmented generations, because the time between the start of fragmentation (year 1970) and our study (year 2008) was less than one generation of this tree species. It should be mentioned that clonal reproduction by sprouting, a common phenomenon in many ??old rare?? tree species, can help E. pleiospermum buffer the genetic impacts of fragmentation by delaying the time between generations. Therefore, we conclude that this ??old rare?? tree species show limited genetic impacts from recent habitat fragmentation. However, the elimination of rare alleles and increase of inbreeding coefficient in the post-fragmentation cohort are early warnings of deleterious genetic consequences of fragmentation. Our results provide valuable information to formulate conservation and restoration guidelines for E. pleiospermum.  相似文献   

19.
Translocation of threatened species is a tool used increasingly to conserve biodiversity, but the suite of co-dependent species that use the threatened taxa as hosts can be overlooked. We investigate the preliminary impact of translocating three threatened plant species on insect species and the integrity of insect assemblages that depend on these plants as their hosts. We compare the insect assemblages between natural populations of the threatened species, related non-threatened plant species growing wild near the threatened plants, and threatened plants translocated to another site approximately 40?km away. We used host breadth models and a coextinction risk protocol to determine which insect species are potentially host-specific on the threatened plants, and then assessed these insects?? potential presence at the translocation site. We found that insect assemblages on naturally-occurring threatened plants had more individuals, higher species density and higher species richness than assemblages on translocated plants. For one plant species, Leucopogon gnaphalioides, species composition differed significantly between wild and translocated populations (P?<?0.001). Furthermore, four insect species that were host-specific to Banksia brownii and B. montana were not detected on the translocated plants. Instead, translocated plants supported insect assemblages more similar to those of related plant species from the surrounding area. We conclude that threatened plant translocations that involve seed collection and propagation may have limited benefit for individual dependent species or the supported insect assemblage. Additional conservation actions will be required to maintain the diversity of insect assemblages and host-dependent relationships.  相似文献   

20.
The genetic erosion of Pistacia germplasm has been highlighted in many reports. In order to emphasize this and to focus more attention on this subject, national and international (especially IPGRI and IFAR) institutions have initiated projects proposing to characterize, collect and conserve Pistacia germplasm. Therefore, this paper reviews recent research concerning conventional (in situ and ex situ) and unconventional biotechnological conservation strategies applied to the preservation of Pistacia germplasm. As regards conventional conservation, the majority of germplasm collections of Pistacia species are preserved on farms (in situ) and in seed and field genebanks (ex situ), as well as in the wild, where they are vulnerable to unexpected weather conditions and/or diseases. Hence, complementary successful unconventional in vitro methods (organogenesis, somatic embryogenesis and micrografting) and slow-growth storage conditions for medium-term preservation of Pistacia are presented together with the morphological and molecular studies carried out for the characterization of its species in this review. Moreover, special attention is additionally focused on cryopreservation (dehydration- and vitrification-based one-step freezing techniques) for the long-term preservation of Pistacia species. Possible basic principles concerning the establishment of a cryobank for the successful conservation of Pistacia germplasm are also discussed.  相似文献   

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