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1.
The origin of lentil from the taxon Lens culinaris subsp. orientalis has been proved by morphological evidence and breeding experiments. This wild form exhibits variation in many characters and is distributed over a vast area from the Middle-East to central Asia. Characters that are polymorphic in the wild progenitor but monomorphic in the cultigen can be utilized for better identification of the genetic stock which gave rise to the domesticated lentil. Three characters of that kind have been identified in lentil: chromosomal architecture, crossability potential and restriction pattern of chloroplast DNA. Nearly all accessions of the cultivated lentil tested to these three characters have been found monomorphic, but considerable polymorphism exists in the wild accessions. Three subsp. orientalis accessions have been shown to share the above characters with the cultigen and hence can be regarded as members of the genetic stock from which lentil was domesticated. These three accessions originated from eastern Turkey and northern Syria.  相似文献   

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Genetic Resources and Crop Evolution - This is the first report evaluating the genetic diversity of Mexican grape species utilizing DNA-based markers to understand the distribution of grape...  相似文献   

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The lipid content and fatty acid composition in the edible meat of twenty-nine species of wild and cultured freshwater and marine fish and shrimps were investigated. Both the lipid content and fatty acid composition of the species were specified due to their unique food habits and trophic levels. Most of the marine fish demonstrated higher lipid content than the freshwater fish, whereas shrimps had the lowest lipid content. All the marine fish and shrimps had much higher total n-3 PUFA than n-6 PUFA, while most of the freshwater fish and shrimps demonstrated much lower total n-3 PUFA than n-6 PUFA. This may be the biggest difference in fatty acid composition between marine and freshwater species. The cultured freshwater fish demonstrated higher percentages of total PUFA, total n-3 PUFA, and EPA + DHA than the wild freshwater fish. Two freshwater fish, including bighead carp and silver carp, are comparable to the marine fish as sources of n-3 PUFA.  相似文献   

4.
Obtaining reliable population size or abundance estimates of endangered species is critical for their conservation and management. Genotyping non-invasively collected samples is an effective way to gain insights into the number and grouping patterns of rare or elusive animals. In this study we used genetic capture-recapture estimators to obtain a precise estimate of the size of a western gorilla population inhabiting an intensely sampled 101 km2 area in Loango National Park, Gabon. Using 394 putative gorilla samples collected opportunistically over a 3 year period, we identified 83 unique genotypes. We used a rarefaction curve, Bayesian estimator and two maximum-likelihood methods to estimate that between 87 and 107 individuals used the study area between February 2005 and September 2007. The confidence interval surrounding the genetic estimate was smaller than that obtained using traditional ape survey methods. In addition, genetic analysis showed that gorilla and chimpanzee faeces were identified with 98% and 95% accuracy in the field, respectively. Patterns of co-occurrence of individual gorillas suggest that at least 11 gorilla social groups and five lone silverback males lived in the study area and that several individuals transferred between groups during the 3-year study period. When properly designed and implemented as part of a long-term biomonitoring program, genetic capture-recapture should prove an invaluable tool for evaluating, even on a large-scale, the population size and dynamics of apes and other elusive species.  相似文献   

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The genetic origin of cultivated papaya is not clear. Wild relatives of papaya (Carica papaya) from central southern America were investigated using isozyme and RAPD analysis. Seven other species (including six from the genus Carica) were found to be relatively distant from papaya providing no indication of the genetic origin of papaya. Isozyme and RAPD data gave similar measures of genetic similarity within this group. C. papaya was about 70% dissimilar to the other Carica species by both methods. The other Carica species had average dissimilarities around 50%. Two species, C. pubescens and C. stipulata were much closer to each other with similarities of 87% by isozyme analysis and 82% by RAPD analysis. Although both methods gave similar measures for genetic distance the large number of RAPD markers available made RAPD analysis more reliable for analysis of the extremes (e.g. closely related taxa may show no isozyme differences and distant taxa may show no isozyme similarities).  相似文献   

7.
Genetic Resources and Crop Evolution - Alliums comprise of popular spices and used for various culinary purposes and nutraceuticals. Poor genetic characterization and scarce information regarding...  相似文献   

8.
Ninety, 21-day-old, Japanese quail (Coturnix coturnix japonica) divided into three groups with five subgroups each were fed a basal diet that served as control or a basal diet containing 5 or 10% of dried tomato pulp (DTP), a byproduct of the tomato-processing industry. The DTP contained lycopene and beta-carotene at 281 and 24.3 mg kg(-)(1) of dry weight, respectively. On day 42 of age, birds were slaughtered, and carcasses were trimmed for breast meat. To assess the effect of dietary treatment on the oxidative stability of raw and cooked meat, raw meat was subjected to iron-induced lipid oxidation, whereas both raw and cooked meats were subjected to refrigerated storage at 4 degrees C. The extent of lipid oxidation was determined on the basis of the malondialdehyde (MDA) formed through the use of third-order derivative spectrophotometry. Results showed that after 6 and 9 days of refrigerated storage, MDA values in raw meat were increased. The increase was higher (P < 0.05) for the 10% DTP group and lower (P < 0.05) for the 5% DTP group, compared to control. An analogous oxidation profile was observed for cooked meat at 3, 6, and 9 days of storage. Iron-induced lipid oxidation of raw meat showed that the 10% DTP group as well as the control group exhibited MDA values that did not differ (P > 0.05) from each other at all time points, whereas the 5% DTP group presented MDA values that, although not differing from those of the other groups at 0 and 50 min, were significantly (P < 0.05) lower than those of the other groups at 100 and 150 min of iron-induced lipid oxidation. These results suggested that inclusion of dried tomato pulp in feed at a level of 5% exerted an antioxidant effect, whereas addition at level of 10% exerted a prooxidant effect. Mean alpha-tocopherol levels in the control, 5% DTP, and 10% DTP groups were 2.2, 2.1, and 1.4 mg kg(-)(1) of meat, respectively. Fatty acid analysis showed that the 10% DTP group had a higher (P < 0.05) content of total polyunsaturated fatty acids and a greater (P < 0.05) unsaturated/saturated fatty acid ratio compared to control. There might be an interaction between DTP and alpha-tocopherol that is of importance for the balance between pro- and antioxidative activities. Future experiments should be designed to explore the interaction between individual carotenoids and tocopherols in order to better elucidate their role in oxidative changes.  相似文献   

9.
Discovery and incorporation of genes from wild species provide means to sustain crop improvement, particularly when levels of resistance in the cultigens are low and virulent strains of pests and pathogens overcome the host plant resistance. The extent of utilization and the potential of the wild genepool for genetic enhancement were reviewed in five important food crops viz. sorghum, pearl millet, chickpea, pigeonpea and groundnut grown in the semi-arid tropics. Introgression from compatible wild germplasm in the primary gene pool resulted in transfer of new cytoplasmic male sterility systems in pearl millet and pigeonpea, development of high protein, cleistogamous flower and dwarf pigeonpea lines and foliar disease resistant groundnut cultivars. Utilization of wild species in secondary and tertiary gene pools has been generally limited due to sterility, restricted recombination or cross incompatibility. Nevertheless, these species are extremely important as they contain high levels of resistance to several important biotic and abiotic stresses. Several of them, like those belonging to the Parasorghum section and the rhizomatous Arachis species are sources of multiple resistances and hold great promise to sustain crop productivity.  相似文献   

10.
Lolium and Festuca are two important genera of cool-season forage and turf grasses worldwide. Lolium temulentum L. (darnel ryegrass) has been proposed as a model species for genomics studies of cool-season forage and turf grasses. A study with 41 darnel ryegrass, three tall fescue (Festuca arundinacea Schreb.), two tetraploid fescue (F. glaucescens), and two meadow fescue (F. pratensis) genotypes was initiated to (i) identify a set of microsatellite (simple sequence repeats) markers useful for L. temulentum L., and (ii) to utilize such markers for assessing the genetic variability of L. temulentum accessions collected from different geographical regions of the world. A total of 40 tall fescue (TF) EST-SSRs and 60 Festuca–Lolium (F × L) genomic SSRs were screened on a subset of eight genotypes. The selected 30 tall fescue EST-SSRs and 32 F × L genomic SSRs were used for further analysis of genotypes. The TF-EST- and the F × L genomic-SSRs identified 10.3 and 9.3 alleles per marker, respectively with an average polymorphic information content (PIC) value of 0.66. The phenogram based on 319 EST-SSR and 296 genomic SSR fragments, grouped L. temulentum accessions into three major clusters except for accession ABY-BA 8892.78. Lolium temulentum accession ABY-BA 8892.78 did not cluster with any other accession. The Festuca clusters were distantly related with darnel ryegrass clusters with a similarity coefficient of 0.26. The selected set of tall fescue EST- and F × L genomic SSRs were useful in assessing L. temulentum genetic diversity and could benefit the genetic improvement of members of the Festuca–Lolium complex.  相似文献   

11.
European native plant diversity is currently suffering erosion and extinction and thus, it is crucial to improve conservation strategies to maintain this essential resource. If unchecked, this genetic erosion and species extinction will cause unnecessary and irreversible harm to the economy and social well being of Europe. Much plant biodiversity is undoubtedly found in the existing 9654 European protected areas that cover 1,066,358 km2, but clearly targeted and active conservation of priority plant species is required within these protected areas. To help ensure more efficient long-term sustainable conservation, a novel approach to the in situ conservation of European plants, notably crop wild relatives, is suggested. The purpose of this approach is to know what plant genetic resources (PGR) we have, where they are located and to assess whether the current network of protected areas includes a representative sample of European PGR diversity. The generation of in situ conservation and management plans for PGR populations in existing protected areas can significantly improve the present conservation status. Additionally, the identification of gaps of certain PGR in current protected areas can provide the basis for the designation of new complementary PGR in situ reserves.  相似文献   

12.
Two strains of Pediococcus pentosaceus were isolated from refrigerated pork and found to produce antimicrobial substances that may inhibit foodborne pathogens and have potential as natural food preservatives. They were named P. pentosaceus L and S. The antimicrobial substances were purified to electrophoretical homogeneity by chloroform extraction and designated pentocins L and S with molecular masses (M) of 27 and 25 kDa, respectively. Both pentocins also had broad inhibition spectra and were thermostable. They inhibit the growth of tested spore-forming G+ and G- strains and the germination of Bacillus subtilis ATCC 10225, B. subtilis ATCC 10254, and Bacillus cereus ATCC 11778 spores. The inhibition activities decreased as the glucose in the medium decreased from 8.0 to 2.0%.  相似文献   

13.
Molecular genetic and chemical assessment of Rhizoma Curcumae in China   总被引:2,自引:0,他引:2  
Rhizoma Curcumae (Ezhu) is a traditional Chinese medicine that has been used in removing blood stasis and alleviating pain for over a thousand years. Three species of Curcuma rhizomes are being used, which include Curcuma wenyujin, Curcuma phaeocaulis, and Curcuma kwangsiensis. In China, the production of Rhizoma Curcumae largely depends on agricultural farming. The essential oils are considered as active constituents in Rhizoma Curcumae, which include curdione, curcumol, and germacrone. On the basis of the yield of curdione, curcumol, and germacrone in an orthogonal array design, the optimized extraction condition was developed. The amounts of these compounds within essential oils in Rhizoma Curcumae varied according to different species and their regions of cultivation. Chemical fingerprints were generated from different species of Curcuma, which therefore could serve as identification markers. In molecular genetic identification of Rhizoma Curcumae, the 5S-rRNA spacer domains of 5 Curcuma species, including the common adulterants of this herb, were amplified, and their nucleotide sequences were determined. Diversity in DNA sequences among various species was found in their 5S-rRNA spacer domains. Thus, the chemical fingerprint together with the genetic distinction could serve as markers for quality control of Curcuma species.  相似文献   

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Six species of the genus Prunus occur inAndalusia. Matters regarding their ecology, ethnobotanical aspectsand conservation are discussed, as well as knowledge about thegermplasm of those species with greater economic importance and theirdegree of conservation, namely: P.avium, P.mahaleb and P.insititia. Various conservation measures areproposed for wild germplasm and for the germplasm of local varieties:a) conservation efforts should target the best populations,except in the case of P.avium and P.insititia, where every individual should beaddressed, including both wild and local cultivars; b) theDehesa del Camarate (Sierra Nevada) is proposed as an areafor in situ germplasm conservation; c) theawareness of the importance of Prunus germplasmshould be increased among forest workers, environmental managers andthe public; d) some silvicultural techniques are proposed, suchas mixed Prunus patches, hedge treatment,Z-tree selection at the early stages and the protection ofroot suckers; e) improved, selected P.avium and P.mahaleb germplasm should be used at highlyproductive sites since these two species can be cultivated as highvalue timber trees; f) some Prunus speciescan also provide profitable NTFPs in the region. Details regardingdifferent collection areas are covered. Finally, some topics arerecommended for scientific research. Three tables and a distributionmap of Prunus species in Andalusia areincluded.  相似文献   

16.
The conservation community has been set a considerable challenge by way of the CBD (Convention on Biological Diversity) 2010 targets. This may not be achievable by 2010 as demanded by the CBD, but at least methodologies can be assessed with a view to their implementation, so that loss of biodiversity and its inherent genetic diversity can be reduced post 2010. There is therefore a need to develop and implement protocols to efficiently measure genetic erosion and to make the identification of the drivers of erosion clear enabling counter-measures to be taken. In this paper the applicability of the indirect genetic erosion threat assessment for wild populations of rare and endemic Vicia species has been investigated. The method applied was based on the scoring of 18 factors perceived to be threats in the 18 study sites in two regions of Syria. Both temporal and spatial patterns of genetic erosion were considered. The method clearly detected spatial patterns of threat, enabling discrimination between the study sites located in the two study regions. However, no significant variation among the sites within each region was detected, highlighting the restricted spatial resolution of the method. Most importantly the results were in agreement with population demographic change observed, confirmed by a highly significant correlation between the erosion threat score and the relative population size change over the last 20 years. The results confirm the great potential of indirect genetic erosion threat assessment in routine evidence-based wild plant conservation decision-making.  相似文献   

17.
In Sicily and in the small surrounding islands the section Brassica of the genus Brassica comprises five species, B. insularis Moris, B. incana Ten., B. macrocarpa Guss., B. rupestris Raf. and B. villosa Biv. These taxa represent a genetic resource as relatives of kale crops but some populations are endangered or threatened, thus isozyme analyses were performed to assess the genetic diversity degree at population and species levels in order to assist the design of conservation management programs.Eleven loci from five enzyme systems (aconitase, leucine aminopeptidase, 6-phosphogluconate dehydrogenase, phosphoglucoisomerase phosphoglucomutase) were analyzed in sixteen natural population (fifteen from Sicily, one from Calabria). Mean within-population genetic diversity was moderate (P = 41%, A = 1.54, H = 0.16). In some cases a great number of heterozygous individuals were detected, in other cases fixation index (F) deviated significantly from Hardy-Weinberg genotypic expectations.A total of 37 alleles was recognized, six of which resulted exclusive to single populations. The among-population component of the total genetic diversity (Gst mean values) for each species was 0.30–0.37, indicating genetic differentiation among populations.Among B. villosa and B. rupestris populations genetic distance values resulted rather low and they resulted high with B. incana and B. macrocarpa populations.The results are discussed with regard to the distribution of the genetic diversity level and the genetic resources management.  相似文献   

18.
The probability and severity of an adverse event can be analyzed by quantitative exposure assessment (QEA). This methodology was applied to model the human health risks associated with the combustion of specified risk material (SRM) derived meat and bone meal (MBM) in a combustion facility. The identification of MBM and SRM as significant factors in the spread of bovine spongiform encephalopathy (BSE) has resulted in restrictions on their use and movement, and this has led to a requirement for alternative end-uses for these products. A stochastic (Latin Hypercube sampling) simulation model was developed to assess the exposure and hence the risks associated with the use of SRM-derived MBM in a combustion facility. The model simulates the potential infectivity pathways that SRM-derived MBM follows, including its production from animals potentially infected with sub-clinical BSE and subsequent processing of the material with segregation and heat treatments. A failure probability was included to take account of sub-optimal operating conditions. Two scenarios, reflecting the infectivity risk in different animal tissues as defined by the European Commission's scientific steering committee (SSC), were performed with 100,000 iterations of the model. Model results showed that the societal exposure to humans resulting from the combustion of SRM-derived MBM is extremely small (mean values ranging from 7.57 x 10(-6) ID50/year to 8.38 x 10(-5) ID50/year). The resulting societal risks are significantly less than the background societal risk of approximately 2.5 cases of sporadic CJD in Ireland each year. A sensitivity analysis revealed that the species barrier had a large impact on exposure calculations and hence should be the focus of further scientific investigation to reduce our uncertainty about this parameter. The model predicts that material spillage into untreated effluent represents the biggest risk to humans, indicating that efforts for risk mitigation should be focused on reducing the potential for spillage.  相似文献   

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