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1.
Pejibaye (Bactris gasipaes) was domesticated and widely used in the lowland humid neotropics during pre-Colombian times. Several research programs are underway to study and improve the species for use by farmers in ecologically suitable regions. Five breeding programs are outlined, each for a use to which the pejibaye may be put: (1) palmito (heart of palm), (2) whole fruit for human consumption, (3) flour and meal production, (4) oil production, and (5) animal ration from residues or purposefully bred varieties. Yield estimates and breeding problems are discussed. It is certain that the pejibaye can again become an important crop for the humid tropics.  相似文献   

2.
One species of hiphomycetos group, belonging to the genus Bipolaris Shoemaker that was identified like Bipolaris bicolor (Mitra) Shoemaker is recorded for the first time on pupunha palm (Bactris gasipaes Kunth) from Brazil. The comparison with other close species reported like pathogenic folial spot in genus Arecaceae is made. Its morphological and cultural characteristics are described.  相似文献   

3.
Bactris gasipaes (Arecaceae), also known as peach palm, was domesticated by Amazonian Indians and is cultivated for its fruit and heart-of-palm, a vegetable grown in the tree’s inner core. Currently, the conservation of this species relies on in situ conditions and field gene banks. Complementary conservation strategies, such as those based on in vitro techniques, are indicated in such cases. To establish an appropriate cryopreservation protocol, this study aimed to evaluate the ultrastructural features of B. gasipaes embryogenic cultures submitted to vitrification and subsequent cryogenic temperatures. Accordingly, somatic embryo clusters were submitted to Plant Vitrification Solution 3 (PVS3). In general, cells submitted to PVS3 had viable cell characteristics associated with apparently many mitochondria, prominent nucleus, and preserved cell walls. Cells not incubated in PVS3 did not survive after the cryogenic process in liquid nitrogen. The best incubation time for the vitrification technique was 240 min, resulting in a survival rate of 37 %. In these cases, several features were indicative of quite active cell metabolism, including intact nuclei and preserved cell walls, an apparently many of mitochondria and lipid bodies, and the presence of many starch granules and condensed chromatin. Moreover, ultrastructure analysis revealed that overall cellular structures had been preserved after cryogenic treatment, thus validating the use of vitrification in conjunction with cryopreservation of peach palm elite genotypes, as well as wild genotypes, which carry a rich pool of genes that must be conserved.  相似文献   

4.
Genetic diversity and kin relationships among wild and cultivated populations of the pejibaye palm (Bactris gasipaes, Palmae) using microsatellite markers. The genetic diversity of the peach palm (Pejibaye, Bactris gasipaes Kunth) was evaluated using four nuclear DNA microsatellites in an effort to elucidate the evolution and domestication of this crop. A total of 258 samples from seven wild populations and eleven races were analyzed. All loci were polymorphic and a total of 50 alleles were identified. Average genetic diversity (0.67) and genetic differentiation among populations (Fst=0.16) were high when all populations were considered. Genetic differentiation was lower when the populations were grouped according to their origin into Western and Eastern populations (Fst=0.13 for both). Gene flow was slightly higher among Western populations (Nm=1.71) than among Eastern populations (Nm=1.62). The Putumayo, Yurimaguas, Vaupés, Tucurrique and Guatuso races seem to have been subjected to intense human selection. Hybrid populations exist in Azuero, Tuira, Cauca, Vaupés, Puerto Ayacucho and Solim?es, probably resulting from exchange and introgressions among sympatric wild and cultivated populations. Genetic distance (Dm) was estimated to determine the degree of relationship among populations using the neighbor-joining method; the wild populations from Maracaibo were used as the outgroup. The populations were divided into three general groups: Maracaibo (B. caribaea, B. macana var veragua and B. macana var arapuey), Eastern Amazon (Tembe, Pará and Acre) and a third group with two subgroups, Western (Azuero, Chontilla, Tuira, Cauca, Tucurrique and Guatuso) and Upper Amazon (B. dahlgreniana, Puerto Ayacucho, Solim?es, Vaupés and Putumayo). The genetic relationships strongly support the hypothesis that peach palm was brought into cultivation independently in no less than three areas: the Western Andes (extending into lower Central America); Upper Amazon (extending into the Solim?es and its tributaries), and the Eastern Amazon (extending from Bolivia to the lower Amazon through the Madeira River).  相似文献   

5.
This paper appraises the role of prehistoric human societies in modifying the natural woodland biodiversity of several regions throughout Scotland. It draws attention to the likelihood that, contrary to popular belief, biodiversity was enhanced by interactions between agricultural communities and woodlands. The possible purposefulness of such interactions is discussed. Mindful of the present concern to re-establish ‘native’ woodlands in many parts of northern Britain, we then review three approaches to the identification of native tree types in Scotland, and conclude that insufficient attention in reafforestation schemes is being paid to (a) the palaeoecological record as a record of native woodland or (b) the likely former high taxonomic diversity of woodlands. Both these failings will lead to the creation of new woodlands lacking in species diversity.  相似文献   

6.
Nutritive assessment of pejibaye (Bactris gasipaes) meals included proximal composition of the lipid and nitrogenous fractions. Caloric values obtained as true metabolizable energy (TME) indicate that the pejibaye has a higher content of energy than corn and that it is not necessary to separate the seeds from the fruits in animal feeds; the level of indispensable aminoacids is considerably low, especially methionine, which is lower than in corn; thin layer chromatography shows that most of the free fatty acids are present in a ratio of 2:1 in unsaturated to saturated acids. The predominant fatty acids in whole pejibaye meal are oleic and palmitic acids with adequate levels of linoleic acid. Saturated fatty acids are predominant in the seed, with a very high content of lauric and myristic acids.  相似文献   

7.
Regrowth capacity and genetic stability of plants recovered following cryopreservation are associated with changes in DNA epigenetics, particularly in DNA methylation levels. In this study, global DNA methylation profiles associated with frequency of regrowth of peach palm (Bactris gasipaes) somatic embryos following cryopreservation using droplet-vitrification were investigated. Somatic embryo clusters (SEC) subjected to plant vitrification solution 3 (PVS3) for different durations (0, 60, 120, 180, and 240 min) were evaluated for regrowth capacity. The highest frequency of regrowth (52.4 %) was obtained when SEC were incubated in PVS3 for 120 min prior to droplet-vitrification cryopreservation. Global DNA methylation profiles were influenced by both cryoprotectants and droplet-vitrification cryopreservation. Incubation of SEC in PVS3 for limited durations not only reduced frequency of regrowth, but also increased DNA methylations levels when compared with proliferating SEC grown in a temporary immersion system. Although SEC subjected to cryopreservation exhibited the highest DNA methylation variation, 120 min SEC incubation in a PVS3 solution resulted in the recovery of initial global methylation profiles after 24 weeks of regrowth.  相似文献   

8.
The fact that pests are the most abundant species in agricultural settings has broadly precluded the attention to non-pest species and the study of temporal dynamics of diversity in agroecosystems. Because, agroecosystems hold increasingly important portions of biological diversity, understanding of non-pest species dynamics in such systems will contribute significantly to their conservation. In addition, deep understanding of both pest and non-pest population dynamics in a community context necessarily requires a long-term approach. By means of the analysis of weekly fruit fly sampling sessions across 12 years, in three tropical fruit orchards, we describe the temporal dynamics of species richness and turnover, structure and composition of Anastrepha fruit fly ensembles considering pest and non-pest species. Furthermore, we ask if time series of non-pest species covariate with time series of pest species, as a way to evaluate the best management scheme to minimize negative impacts of pest control on non-pest species. Among 18 Anastrepha fruit fly species detected over 12 years, five were considered as pest species. Fruit fly ensembles were characterized by strong seasonal dynamics composed of annual cycles. Sapodilla was the most diverse orchard. Overall, fruit fly ensembles appeared stable throughout time. The temporal dynamics of non-pest species covaried positively with temporal dynamics of pest abundance, with consequent management implications. Results suggest that in mango and grapefruit orchards, pest control could be focused during time periods with low potential impact on non-pest species; while in sapodilla orchards other approaches should be developed. The approach described here could be used in agroecosystems to minimize the impact of pest management on non-pest species particularly in highly anthropized landscapes and human-managed ecosystems were biodiversity conservation is a high priority.  相似文献   

9.
Coastal-marine biodiversity conservation must focus increasingly at the level of the land- and seascape. Five cases illustrate discontinuities and synergisms and how system changes may take place. For Caribbean coral reefs, the result of overfishing and disease has been a shrinkage in the entire system, the effects of which may cascade through the coastal seascape. For Beringia, patterns of benthic diversity are best understood in a manner that matches the multiscale, integrated dynamics of weather, ice, marine mammal feeding, and community structure. In the case of US East Coast estuaries, oyster reefs may be keystone elements, with important effects on functional diversity. Large-scale coastal systems depend upon the connectivity of fresh and marine waters in the coastal zone, having implications for the apparent stochasticity of coastal fisheries. And, for a coastal barrier-lagoon site, a state change may be described in terms of a combination of succession, the attainment of a quasi-equilibrium state, and disturbance. A profound problem for conservation is that there is very little information about the relationship between species diversity and ecological function. Coastal-marine biodiversity conservation is best addressed at the level of the land- and seascape.  相似文献   

10.
Originally prepared as a keynote address for the 2008 La Tapoa Workshop on Natural Resource Management (NRM) and Community Based Natural Resource Management (CBNRM), this paper examines the Southern African experience in CBNRM over the past 20 years. From this experience the paper draws lessons on when and where CBNRM is appropriate, what can make it work, and what can make it work better. These lessons are discussed under the three categories of benefit, conservation and empowerment. Benefit is usually conceptualized in terms of financial revenue, and using a Zimbabwean case study the paper shows how in unusual circumstances this can be substantial. Normally, however, natural resource production can only supplement inputs from agriculture and other modes of production, and the paper warns against regarding CBNRM as a panacea for rural poverty. Benefit should also be understood in non-pecuniary terms, and when economic benefit is linked with authority and responsibility large increments in social capital can result. The conservation interests of donors are often perceived as being at odds with local perspectives, a perception which fails to take into consideration means-end-sequencing. A socially constructed stalemate often occurs when external agencies impose their agendas upon local populations, a stalemate which can be broken when communities are given the authority and responsibility necessary to create internally legitimate regimes. A new science which combines professional and civil inputs is required to achieve CBNRM’s goal—empowered and dynamic local regimes integrated into larger scale systems of conservation and development.  相似文献   

11.
The knowledge of species occurrence within an area is crucial to develop proper conservation strategies to protect species diversity. Biosphere Reserves (BRs), established to preserve biodiversity and sustainably use their resources, should therefore have precise information of its biodiversity. We compared and evaluated information on threatened and non-threatened vertebrate species available for Spanish BRs from three sources: management documents (MDs), the Global Biodiversity Information Facility index (GBIF), and atlases and red books. Our results suggest that information from any one source was rather partial, to a degree that depended on which vertebrate group was considered. Management documents did list a high percentage of threatened species found in BRs, reaching up to the total number of species of birds and mammals. Species lists overlap between all three sources ranged from 59 % for fish to 84 % for mammals. In addition, there is an inconsistency between national and international threatened species categories and it should thus call for revisions. Even though the information of non-threatened and threatened species occurrence in MDs of Spanish BRs is good, it is necessary to pay attention to amphibian and fish species which are less recorded.  相似文献   

12.
The access to new molecular markers is not always possible for all researchers, due to limited laboratory and economical resources. A new technique, called AFLP, seems to be a simple and robust method to obtain a large number of variable molecular markers. In this article I show the results of AFLP analysis in three different conservation projects requiring different level of genetic variability. I also compare the multi-locus AFLP results with single-locus markers (microsatellites) and haploid organellar marker (mtDNA) sequences. The results suggest that the AFLP technique could be very useful in a wide range of conservation studies.  相似文献   

13.
We review the uses of fossil insects, particularly Coleoptera (beetles) and Chironomidae (non-biting midges) from ancient deposits to inform the study of wetland ecosystems and their ecological and restoration processes. In particular, we focus on two contrasting ecosystems, drawing upon research undertaken by us on British raised mire peats and shallow lake systems, one an essentially terrestrial ecosystem, the other aquatic, but in which wetland insects play an important and integral part. The study of raised mire peats suggests that faunal stability is a characteristic of these wetland systems, over what appear to be extensive periods of time (up to several millennia), whilst studies of shallow lake ecosystems over recent timescales indicates that faunal instability appears to be more common, usually driven by increasing eutrophication. Drawing upon a series of fossil Coleoptera records spanning several thousand years from Hatfield Moors, south Yorkshire, we reconstruct in some detail the mire’s ontogeny and fluctuations in site hydrology and vegetation cover, illustrating the intimate association between substrate, topography and peat development. A comparison between fossil and modern beetle populations indicates that the faunal characteristics of this mire and its adjacent neighbour, Thorne Moors, become established during the early phases of peat development, including its rare endemics, and that the faunal biodiversity on the sites today is dictated by complex site histories. The over-riding characteristic of these faunas is of stability over several thousand years, which has important implications for the restoration of degraded sites, especially those where refugial areas are limited. In contrast, analyses of fossil Chironomidae from shallow lakes allow researchers to track changes in limnological status and while attempts have been made to reconstruct changes in nutrient levels quantitatively, the chironomids respond indirectly to such changes, typically mediated through complex ecosystem dynamics such as changes in fish and/or macrophyte communities. These changes are illustrated via historic chironomid stratigraphies and diversity indices from a range of shallow lakes located across Britain: Slapton Ley, Frensham Great Pond, Fleet Pond, Kyre Pool and Barnes Loch. These sites have shown varying degrees of eutrophication over recent timescales which tends to be associated with a decline in chironomid diversity. While complex functional processes exist within these ecosystems, our evidence suggests that one of the key drivers in the loss of shallow lake chironomid diversity appears to be the loss of aquatic macrophytes. Overall, while chironomids do show a clear response to altered nutrient regimes, multi-proxy reconstructions are recommended for a clear interpretation of past change. We conclude that if we are to have a better understanding of biota at the ecosystem level we need to know more of the complex interactions between different insect groups as well as with other animal and plant communities. A palaeoecological approach is thus crucial in order to assess the role of insect groups in ecosystem processes, both in the recent past and over long time scales, and is essential for wetland managers and conservation organisations involved in long term management and restoration of wetland systems  相似文献   

14.
Despite an increasing amount of data on the effects of tropical land use on continental forest fauna and flora, it is debatable whether the choice of the indicator variables allows for a proper evaluation of the role of modified habitats in mitigating the global biodiversity crisis. While many single-taxon studies have highlighted that species with narrow geographic ranges especially suffer from habitat modification, there is no multi-taxa study available which consistently focuses on geographic range composition of the studied indicator groups. We compiled geographic range data for 180 bird, 119 butterfly, 204 tree and 219 understorey plant species sampled along a gradient of habitat modification ranging from near-primary forest through young secondary forest and agroforestry systems to annual crops in the southwestern lowlands of Cameroon. We found very similar patterns of declining species richness with increasing habitat modification between taxon-specific groups of similar geographic range categories. At the 8 km(2) spatial level, estimated richness of endemic species declined in all groups by 21% (birds) to 91% (trees) from forests to annual crops, while estimated richness of widespread species increased by +101% (trees) to +275% (understorey plants), or remained stable (-2%, butterflies). Even traditional agroforestry systems lost estimated endemic species richness by -18% (birds) to -90% (understorey plants). Endemic species richness of one taxon explained between 37% and 57% of others (positive correlations) and taxon-specific richness in widespread species explained up to 76% of variation in richness of endemic species (negative correlations). The key implication of this study is that the range size aspect is fundamental in assessments of conservation value via species inventory data from modified habitats. The study also suggests that even ecologically friendly agricultural matrices may be of much lower value for tropical conservation than indicated by mere biodiversity value.  相似文献   

15.
Electrophoretic analysis of 18 allozyme loci was used to estimate the levels and structuring of genetic variation within and among natural populations of the protected endemic palm species from the Canary Islands (Phoenix canariensis) to evaluate its genetic relationship with the widespread congener P. dactylifera, and to assess comparatively the genetic variation in the populations where the two species coexist with morphologically intermediate plants (mixed populations). Our survey revealed that the within-population component explains roughly 75% of the genetic variation levels detected in P. canariensis (A=1.59; P=41.8; He=0.158), which rank higher than those reported for other species of the Arecaceae. A Principal Component analysis (PCA) based on allele frequencies consistently separates populations of P. canariensis and P. dactylifera, and reveals a close genetic relationship between P. canariensis and the mixed populations. Reduced levels of genetic variation in P. canariensis with respect to P. dactylifera, the fact that the genetic makeup of the Canarian endemic (with no unique alleles) is a subset of that found in P. dactylifera, and the high genetic identity between both species strongly suggest that P. canariensis is recently derived from a common ancestor closely related to P. dactylifera.  相似文献   

16.
Home gardens have received increasing attention and have been insistently presented as hotspots for agro-biodiversity over the last decades. However, apart from their exceptional high plant species diversity, there is little quantitative evidence of the effectiveness of plant species conservation in home gardens. This study examined this issue by assessing (i) the size and membership of garden flora and the contribution to the maintenance of the national flora, (ii) how home garden flora connects to the larger ecosystem it belongs to and (iii) the conservation status of plant species at the home garden level. 360 home gardens distributed in three agro-ecological zones and nine phyto-geographical districts in Benin were visited and inventoried. Diversity parameters at different taxonomic levels were calculated. Species accumulation and spatial occupancy, multivariate methods and rarity index were also used for data analysis. Findings showed that the 360 studied home gardens hosted up to 14.21% of plant species and 44.32% of plant families of the national flora. Home garden flora was constantly dominated by exotic plant species but strongly connected to their surrounding ecosystems, being composed of at least 60% of plant species from their phyto-geographical districts. Finally, home garden plant species were mostly rare and threatened at the home garden level. In this study, we acknowledge the contribution of home gardens to the maintenance of plant species diversity at regional and global levels than local level. Based on the observed prevalence of exotic species, HG effectiveness in sustainably conserving native plant species biodiversity remains questionable.  相似文献   

17.
To detect differences in the information available on freshwater fish species found in Mexican biosphere reserves, the number of species considered in three sources of information: management programmes, Global Biodiversity Information Facility (GBIF) and the scientific literature were compared. Additionally, management actions for the reserves were evaluated. More than 55% of freshwater fish species registered for the reserves were found only in one of the three sources of information, while just 12% was shared among all the three. Fifteen threatened species were registered in GBIF and the scientific literature that were not found in management programmes. Although all the management programmes described conservation actions, none of them gave details about how they would be implemented. Lack of communication among the sources studied, unawareness of the existence of threatened species and the absence of detailed management actions hinder the development of adequate conservation strategies.  相似文献   

18.
Cryobiology offers an important opportunity to assist in the management and study of wildlife, including endangered species. The benefits of developing genome resource banks for wildlife are profound, perhaps more so than for traditional uses in terms of livestock and human fertility. In addition to preserving heterozygosity and assisting in the genetic management of rare populations held in captivity, frozen repositories help insure wild populations against natural and human-induced catastrophes. Such banks also are an invaluable source of new knowledge (for basic and applied research) from thousands of species that have yet to be studied. However, it is crucial that genome resource banks for wildlife species be developed in a coordinated fashion that first benefits the conservation of biodiversity. Spurious collections will be of no advantage to genuine conservation. The Conservation Breeding Specialist Group (CBSG; of the International Union for the Conservation of Nature and Natural Resources' Species Survival Commission) has promoted international dialogue on this topic. CBSG working groups have recognized that such repositories be developed according to specific, scientific guidelines consistent with an international standard that ensures practicality, high-quality ethics, and cost-effectiveness. Areas requiring priority attention also are reviewed, including the need for more basic research, advocacy, and support for developing organized repositories of biomaterials representing the world's diverse biota.  相似文献   

19.
Biodiversity loss poses a real threat to the livelihoods, food security and health of the poor. In Vietnam, nearly 700 species are threatened with national extinction and over 300 species are threatened with global extinction. Deforestation is the main contributor to these biodiversity losses. This study examines biodiversity conservation attitudes of foresters and proposes policy options to promote biodiversity in planted forests. A household survey of 291 foresters in Yen Bai Province, Vietnam, was conducted to examine attitudes to biodiversity conservation. A range of forest policy tools was investigated to find the most appropriate one to enhance biodiversity, given the specific social-economic conditions of foresters. A forest-level optimisation model was employed to design the optimal level of payment for biodiversity conservation. The results suggest that a large number of foresters would agree to the idea of enhancing biodiversity in planted forests if they were financially supported. It is concluded that policy options for the Government of Vietnam include refinements to the current payment scheme and considering increasing the payment level to foresters to enhance biodiversity. These findings may have some generalisability to the plantation forestry sector in other developing countries in tropical zones, and implications for implementing the REDD+ mechanism in developing countries.  相似文献   

20.
Marine biodiversity and its distribution in the New Zealand region were determined using historical data for an appropriate indicator taxon, the Bryozoa. Bryozoans were identified as belonging to three communities, termed Intertidal/Shelf/Slope (ISS) and Deep-Sea 1 and 2 (DS1 and DS2). Biodiversity was assessed using measures based on relatedness of species, average taxonomic distinctness and variation in taxonomic distinctness. High values of biodiversity for the ISS community are particularly concentrated at both ends of two main islands of New Zealand; the biogenic substratum of the Three Kings Plateau and Foveaux Strait. High values of biodiversity for the DS1 community were primarily located on the seamounts of the northern edge of the Chatham Rise. Values of biodiversity for stations comprising the DS2 community were generally low. The relationship between bryozoan community composition/biodiversity and depth suggested that habitat availability/heterogeneity, sedimentary perturbation and primary productivity could be evoked to explain the pattern of biodiversity observed. The results of the study indicate particular areas of the shelf and deep-sea environment that could be protected in order to conserve New Zealand's marine biodiversity.  相似文献   

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