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1.
2.
In India, food-grade agar is produced from Gracilaria edulis while bacteriological-grade agar is extracted from Gelidiella acerosa. Agarose is directly obtained from Gracilaria dura. Seaweeds for agar production mainly come from wild stocks located in reefs of the Gulf of Mannar, southeast coast. Landings of Gr. edulis were peak (982 dry t) during 1990 while landings of Ge. acerosa reached maximum (665 dry t) during 2002–2003. Overexploitation is leading to a decrease in biomass of these two algae at an alarming rate for the last decade. Commercial cultivation of agarophytes is yet to increase in India in spite of growing pressure on wild stocks triggered by increase in demand of raw material by the industry. Taking this into consideration, a number of efforts have been initiated to develop feasible cultivation methods for agarophytes. The present paper summarizes various methods developed for commercial cultivation of Gr. edulis, Gr. dura, Gracilaria verrucosa and Ge. acerosa in the open sea. We also discuss the challenges in the development of commercial farming of agarophytes in India.  相似文献   

3.
Understanding the use of small bridges and culverts by wildlife to cross the Qinghai–Tibet railway will aid in the design of wildlife crossing structures for similar transportation infrastructure. From 2014 to 2016, 36 infrared cameras were placed inside 14 small bridges and 11 culverts along the Qinghai–Tibet railway to determine the structures’ effectiveness as wildlife passages. Thirteen species of mammals were found to use the small bridges and culverts to cross the railway. The crossing rates for all mammals were significantly higher for small bridges than for culverts. Tibetan antelope (Pantholops hodgsonii), Tibetan gazelle (Procapra picticaudata), kiang (Equus kiang), and wild yak (Bos mutus) preferred small bridges over culverts to cross the railway. In contrast, mountain weasel (Mustela altaica) and Asian badger (Meles leucurus) preferred culverts to cross the railway. The crossing rates of all mammals, particularly Tibetan gazelle and woolly hare, were positively influenced by structure width. Structure height had a positive influence on wild yak, but structure length had a negative influence on kiang. The distance to the highway had a positive influence on the crossing rates of all mammals, particularly wild yak and woolly hare. Human use of the structures had no influence on the crossings of most mammals except for common wolf. We suggest that road design schemes include large and open crossing structures to benefit most species with limitations on human activities near wildlife passages.  相似文献   

4.
Wildlife species damaging crops can cause substantial losses to farmers and at the same time create negative attitudes against wildlife and conservation efforts that may result in negative interactions against wildlife and lead to human-wildlife conflicts (HWCs). For the analysis of negative interactions between humans and terrestrial wildlife species, a globally applicable scheme for monitoring was developed and applied over 6 years in study areas of two Asian (Nepal and India) and two African (Zambia and Tanzania) countries. Factors influencing crop consumption by eight different groups of herbivores were monitored and analyzed using generalized linear models. Seasonality, crop availability, type and the phenological stage of the crop seem to play an important role in the crop damaging behavior of herbivores. Crop consumers such as elephants (Loxodonta africana and Elephas maximus), zebra (Equus quagga spp.) and boars/hogs (Sus scrofa, Potamocherus larvatus and Phacochoerus africanus) show preferences for harvested and/or maturing crops. Rhinos (Rhinoceros unicornis) and antelopes/deer (Taurotragus oryx, Aepyceros melampus, Boselaphus tragocamelus and Axis axis) damage the highest numbers of fields with crops at an intermediate growth stage. The findings of this study can inform management of HWCs in areas where people and wildlife coexist. Furthermore, this study demonstrates the benefits of standardized HWC assessments in order to compare data from different continents and between different species to be able to draw generalized conclusions for the management of HWC.  相似文献   

5.

Background

The swine-adapted serovar Choleraesuis of Salmonella enterica subspecies enterica is found rarely in domestic pigs in Germany. However, a considerable and increasing number of S. Choleraesuis organisms have been isolated from wild boars in Germany in recent years. To investigate a possible epidemiological context, S. Choleraesuis strains from a regional German wild boar population and other hosts were characterised by genotyping methods.

Results

Macrorestriction analysis, biochemical differentiation and antimicrobial susceptibility typing enabled the identification of several clusters of S. Choleraesuis. Some clusters occurred almost permanently in a certain district, whereas other groups circulated among different wild boar herds in larger regions. Non-porcine hosts were infected with the same cluster as the wild boars.

Conclusions

The emergence of S. Choleraesuis in wild boars might be caused by a higher prevalence in the wild boar population, but also the higher awareness to infections with African swine fever may have resulted in a higher number of examined animals. Separation of wild boar populations and, as a result, also the diverse S. Choleraesuis organisms might be due to natural barriers and artificial barriers like arterial roads. The findings of S. Choleraesuis in domestic pigs emphasize the importance of strict biosecurity measures to prevent transmission from wild boars of this but also other pathogens. To avoid risks for humans by zoonotic pathogens regular inspections of meat from wildlife need to be conducted.
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6.
We summarize the research on Asian Sun catfish, Horabagrus brachysoma (Günther), an endemic and threatened freshwater catfish from Western Ghats of India, and provide a comprehensive review of its taxonomy, distribution, biology, population, conservation and aquaculture. Although described in 1864, the taxonomy of H. brachysoma, particularly its familial affinities, continues to be in flux. The species, originally described from the erstwhile ‘state of Cochin’ in present day Kerala State, India, has a current distribution ranging from southern Kerala (8°N) to southern Maharashtra (16°N), where they are found in lowland westward-flowing rivers, as well as natural freshwater lakes and backwaters. As a much relished food fish, H. brachysoma is exploited throughout its range, predominantly through an unmanaged artisanal fishery. Although there are no scientific estimates of either the status or trends in overall population of this endemic catfish, anecdotal evidence and fisher-knowledge suggests drastic declines of several local populations. The fishery for H. brachysoma in the Periyar and Achenkovil rivers in the State of Kerala has been documented to be unsustainable. As a result of an overall population decline of 35 % due to overharvest and habitat loss, H. brachysoma is assessed as ‘Vulnerable’ on the IUCN Red List of Threatened Species?. Primary research on various aspects of feeding, reproductive biology and demography has generated a wealth of information on the species, but this knowledge is yet to be utilized for the development and implementation of in situ conservation or management plans. In view of its high consumer demand, efficient biological and eco-physiological characteristics, as well as the availability of a captive breeding technology, H. brachysoma is considered an emerging species for small-scale aquaculture. Priorities for scientific research to address knowledge-gaps, as well as strategies for effective conservation of this threatened freshwater catfish are discussed.  相似文献   

7.
Natural infection of captive nonhuman primates (NHPs) with Trypanosoma cruzi (agent of Chagas disease) is an increasingly recognized problem in facilities across the southern USA, with negative consequences for NHP health and biomedical research. We explored a central Texas NHP facility as a nidus of transmission by characterizing parasite discrete typing units (DTU) in seropositive rhesus macaques (Macaca mulatta), identifying the wildlife reservoirs, and characterizing vector infection. In seropositive NHPs, we documented low and intermittent concentrations of circulating T. cruzi DNA, with two DTUs in equal proportions, TcI and TcIV. In contrast, consistently high concentrations of T. cruzi DNA were found in wild mesomammals at the facility, yet rodents were PCR-negative. Strong wildlife host associations were found in which raccoons (Procyon lotor) harbored TcIV and opossums (Didelphis virginiana) harbored TcI, while skunks (Mephitis mephitis) were infected with both DTUs. Active and passive vector surveillance yielded three species of triatomines from the facility and in proximity to the NHP enclosures, with 17% T. cruzi infection prevalence. Interventions to protect NHP and human health must focus on interrupting spillover from the robust sylvatic transmission in the surrounding environment.  相似文献   

8.
Prunus yedoensis Matsumura is one of the popular ornamental flowering cherry trees native to northeastern Asia, and its wild populations have only been found on Jeju Island, Korea. Previous studies suggested that wild P. yedoensis (P. yedoensis var. nudiflora) is a hybrid species; however, there is no solid evidence on its exact parental origin and genomic organization. In this study, we developed a total of 38 nuclear gene-based DNA markers that can be universally amplifiable in the Prunus species using 586 Prunus Conserved Orthologous Gene Set (Prunus COS). Using the Prunus COS markers, we investigated the genetic structure of wild P. yedoensis populations and evaluated the putative parental species of wild P. yedoensis. Population structure and phylogenetic analysis of 73 wild P. yedoensis accessions and 54 accessions of other Prunus species revealed that the wild P. yedoensis on Jeju Island is a natural homoploid hybrid. Sequence-level comparison of Prunus COS markers between species suggested that wild P. yedoensis might originate from a cross between maternal P. pendula f. ascendens and paternal P. jamasakura. Moreover, approximately 81% of the wild P. yedoensis accessions examined were likely F1 hybrids, whereas the remaining 19% were backcross hybrids resulting from additional asymmetric introgression of parental genotypes. These findings suggest that complex hybridization of the Prunus species on Jeju Island can produce a range of variable hybrid offspring. Overall, this study makes a significant contribution to address issues of the origin, nomenclature, and genetic relationship of ornamental P. yedoensis.  相似文献   

9.
This study aimed to isolate acaricidal active fractions from acetone extract of Aloe vera L. and investigate the toxicity of these fractions against Tetranychus cinnabarinus (T. cinnabarinus) and Panonychus citri (P. citri). Acetone extract of A. vera L. was isolated by immersing in acetone for 72 h, and diverse fractions were fractionated by column chromatography. The acaricidal activity of each fractions was evaluated by corrected mortality of T. cinnabarinus through slide-dip bioassay. The 8th and 13th fractions of acetone extract with good acaricidal activity were indentified by LC/MS, and the toxicity of these two fractions to T. cinnabarinus and P. citri was identified by regression analysis. Acetone extract of A. vera L. exhibited obvious acaricidal activity, from which a total of 18 fractions were isolated. The 8th and 13th fractions with strong acaricidal activity against T. cinnabarinus were identified to be 3-O-alpha-d-mannopyranosyl-d-mannopyranose (OAMM) and aloe emodin. When compared with spirodiclofen, both OAMM and aloe emodin exhibited higher toxicity to T. cinnabarinus, while only OAMM exhibited a higher toxicity to P. citri (P < 0.05). OAMM and aloe emodin isolated from acetone extract of A. vera L. exhibited obvious acaricidal activities against T. cinnabarinus and P. citri.  相似文献   

10.
Despite the paraquat-resistant mutants that have been reported in plants, this study identified a novel A. thaliana mutant (pqr2) from an XVE inducible activation library based on its resistance to 2 μM paraquat. The pqr2 mutant exhibited a termination mutation in the exon of AT1G31830/PAR1/PQR2, encoded a polyamine uptake transporter AtPUT2/PAR1/PQR2. The PQR2 mutation could largely reduce superoxide accumulation and cell death in the pqr2 plants under paraquat treatment. Moreover, compared with wild type, the pqr2 mutant exhibited much reduced tolerance to putrescine, a classic polyamine compound, which confirmed that PQR2 encoded a defective polyamine transporter. Notably, co-treated with ABA and paraquat, both pqr2 mutant and wild type exhibited a lethal phenotype from seed germination, but the wild type like pqr2 mutant, could remain paraquat-resistance while co-treated with high dosage of Na2WO4, an ABA synthesis inhibitor. Gene expression analysis suggested that ABA signaling should widely regulate paraquat-responsive genes distinctively in wild type and pqr2 mutant. Hence, this study has for the first time reported about ABA negative effect on paraquat-resistance in A. thaliana, providing insight into the ABA signaling involved in the oxidative stress responses induced by paraquat in plants.  相似文献   

11.

Key message

Allotetraploidization drives Glu-1Ay silencing in polyploid wheat.

Abstract

The high-molecular-weight glutenin subunit gene, Glu-1Ay, is always silenced in common wheat via elusive mechanisms. To investigate its silencing and heredity during wheat polyploidization and domestication, the Glu-1Ay gene was characterized in 1246 accessions containing diploid and polyploid wheat worldwide. Eight expressed Glu-1Ay alleles (in 71.81% accessions) and five silenced alleles with a premature termination codon (PTC) were identified in Triticum urartu; 4 expressed alleles (in 41.21% accessions), 13 alleles with PTCs and 1 allele with a WIS 2-1A retrotransposon were present in wild tetraploid wheat; and only silenced alleles with PTC or WIS 2-1A were in cultivated tetra- and hexaploid wheat. Both the PTC number and position in T. urartu Glu-1Ay alleles (one in the N-terminal region) differed from its progeny wild tetraploid wheat (1–5 PTCs mainly in the repetitive domain). The WIS 2-1A insertion occurred?~?0.13 million years ago in wild tetraploid wheat, much later than the allotetraploidization event. The Glu-1Ay alleles with PTCs or WIS 2-1A that arose in wild tetraploid wheat were fully succeeded to cultivated tetraploid and hexaploid wheat. In addition, the Glu-1Ay gene in wild einkorn inherited to cultivated einkorn. Our data demonstrated that the silencing of Glu-1Ay in tetraploid and hexaploid wheat was attributed to the new PTCs and WIS 2-1A insertion in wild tetraploid wheat, and most silenced alleles were delivered to the cultivated tetraploid and hexaploid wheat, providing a clear evolutionary history of the Glu-1Ay gene in the wheat polyploidization and domestication processes.
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12.
The aim of this study was to assess whether animal tuberculosis (TB) is transmitted between free-living European bison (Bison bonasus caucasicus), wild boars (Sus scrofa), and protected carnivores such as grey wolves (Canis lupus), brown bears (Ursus arctos), and Eurasian lynx (Lynx lynx) in the Bieszczady Mountains in Southern Poland. Results of animal studies suggest that TB transmission from bison or wild boars to grey wolves is possible. These are the first described cases where Mycobacterium caprae was detected in samples collected from grey wolves.  相似文献   

13.
The phylogeny and evolution of the microRNA families, miR820 and miR396, was analysed across the AA genomes of the Oryza species, the close relatives of domesticated rice. A highly dynamic evolution of the miR820 family was revealed. The number of copies of MIR820 genes, their chromosomal location and the mature microRNA sequence varied greatly with a total of 16 novel miR820 variants being identified. The phylogeny of pre-MIR820 sequences revealed that MIR820 genes of recently evolved Oryza AA genomes may have derived from sequence divergence of one or a few ancestral genes found in wild Australian perennial rice populations, Taxon B (jpn2)-MIR820 genes. Genomic scale duplication played an important role in the evolution of some of the miR396 family genes in AA genome Oryza species. miR396 family contained a MIR396 gene cluster (MIR396a and MIR396c) which was conserved across the cereal genomes. Nucleotide diversity analysis at these two MIR396 loci revealed that domesticated rice has retained less than 10% of the total diversity present in wild species. In contrast, the nucleotide sequence of four MIR396 loci remained almost conserved across domesticated and wild rices, indicating that they were under extreme functional constraint and may be involved in regulating some fundamental processes which are important both for wild and domesticated rices. Expression analysis demonstrated that miR820 variants were expressed in O. glaberrima O. barthi and O. longistaminata genome. These findings pose new challenges to explain the possible role of miR820 variants identified.  相似文献   

14.
Bacterial bioluminescence was applied to detection of general toxicity (MIT test) and genotoxicity (SOS-lux test) of some chemicals, seawater, and fresh water. The SOS-induced luminescence of E. coli WP2s (cda::luxCDABE) cells was higher than in E. coli C 600 (cda::luxCDABE) at 37°C and pH 6.5. The mutagenic effect of N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), mitomycin C, and hydrogen peroxide determined from the induction of E. coli WP2s cell luminescence was detected at lower concentrations than in the assessment of reversion frequencies. General toxicity was demonstrated by using luminescence inhibition for hydrogen peroxide, Zn2+, and Cd2+ at low concentrations. Regions of the Krasnodar Krai where sea and fresh waters exerted toxic action on luminescence were determined by the microbioluminescent method.  相似文献   

15.
Eight pairs of chloroplast DNA (cpDNA) universal primers selected from 34 pairs were used to assess the genetic diversity of 132 pear accessions in Northern China. Among them, six amplified cpDNA fragments showed genetic diversity. A total of 24 variable sites, including 1 singleton variable site and 23 parsimony informative sites, as well as 21 insertion-deletion fragments, were obtained from the combined cpDNA sequences (5309–5535 bp). Two trnL-trnF-487 haplotypes, five trnL-trnF-413 haplotypes, five rbcL haplotypes, six trnS-psbC haplotypes, eight accD-psaI haplotypes and 12 rps16-trnQ haplotypes were identified among the individuals. Twenty-one haplotypes were identified based on the combined fragments. The values of nucleotide diversity (Pi), average number of nucleotide differences (k) and haplotype diversity (Hd) were 0.00070, 3.56408 and 0.7960, respectively. No statistical significance was detected in Tajima’s D test. Remarkably, the important cpDNA haplotypes and their representing accessions were identified clearly in this study. H_19 was considered as one of the ancient haplotypes and was a divergent centre. H_16 was the most common haplotype of the wild accessions. H_2 was the haplotype representing the most pear germplasm resources (46 cultivars and two wild Ussurian Pear accessions), followed by haplotype H_5 (30 cultivars, two wild Ussurian Pear accessions and four sand pears in outgroups) representing the cultivars ‘Dangshan Suli’ and ‘Yali’, which harbour the largest and the second largest cultivation areas in China. More importantly, this study demonstrated, for the first time, the supposed evolution routes of Pyrus based on cpDNA divergence in the background of pear phylogeny in Northern China.  相似文献   

16.
Commercial exploitation of wild yams (Dioscorea spp.) was once a pillar of the Mexican economy and is currently practiced in the USA and Asia. However, no such activity has yet been reported in South America, the continent richest in Dioscorea species. Upon discovery of wild Dioscorea tubers in marketplaces in Bogotá, Colombia, we sought to (1) identify the species being sold, (2) document the medicinal properties attributed to them, and (3) conduct a preliminary characterization of the market for this product in the capital. During the years 2010, 2012, and 2013, 226 semi-structured interviews were conducted with vendors in 82 medicinal plant stalls distributed in marketplaces throughout Bogotá. Tubers of four native species were identified, all wild-harvested: D ioscorea coriacea, Dioscorea lehmannii, Dioscorea meridensis, and Dioscorea polygonoides; all were sold under the generic name zarzaparrilla, with D. coriacea being the most prevalent species. All vendors interviewed recommended Dioscorea spp. for treating “ailments of the blood,” with “blood cleanser,” and lowering triglycerides and cholesterol as the most often-cited specific uses. Total estimates of sales of wild yams over the study period averaged 488 kg/week, extrapolated to over 25,000 kg/year, with yearly sales varying between 5% and 6% around the mean. This is the first report of raw tubers of any Dioscorea species being commercialized for the treatment of blood or metabolic disorders in Latin America, and the data suggest there is a robust market established in Bogotá. In the interest of public health, pharmacological studies should be undertaken to test the biological activity of these species and to rule out toxicity. We especially recommend population studies of D. coriacea to provide baseline data for sustainable management of this non-timber forest product.  相似文献   

17.
Endelus (Kubaniellus) indicus sp. n. from India, E. (K.) lao sp. n. and E. (K.) khnzoriani sp. n. from Laos, E. (s. str.) sausai sp. n. from China, and E. (s. str.) dembickyi sp. n. from India are described, the two latter species are included in the Endelus bicarinatus Théry, 1932 species-group recently established by the author. E. collinus Obenberger, 1922 is included in this group; lectotype of this species is designated. Keys to species of the subgenus Kubaniellus and of the E. collinus group are provided. E. (K.) kareni Kalashian is for the first time recorded for Shaanxi Prov., E. pacholatkoi Kalashian, E. smaragdinus Desc. et Vill., and E collinus Obenb., for Laos (the latter species, also for Myanmar).  相似文献   

18.
Infestation by the ectoparasitic mite Sarcoptes scabiei (Acari: Sarcoptidae) has important implications for global wildlife conservation and both animal and human health. Ribosomal and mitochondrial DNA sequences of parasites are useful to determine genetic diversity and to describe their likely dynamic evolution. In this study, we described the genetic diversity of S. scabiei individuals collected from wild animals in China by sequencing the ribosomal ITS-2 and mitochondrial 16S rRNA genes. A total of 13 Sarcoptes isolates of wildlife, coupled with one of rabbit origin, were subjected to genetic characteristics. After cloning and sequencing, 14 ITS-2 sequences and 12 16S rRNA sequences were obtained and analyzed. Further analysis of haplotype network and population genetic structure revealed that there were 79 haplotypes in ITS-2 (main haplotype H2) and 31 haplotypes in 16S rRNA (main haplotype C10). The phylogenetic trees showed some partial clustering by location and host, and the analysis of gene polymorphism may prompt that all isolates of S. scabiei have a similar origin. We speculate that the genetic evolution of S. scabiei may be related with that of the hosts, but more research is necessary to better understand the host-parasite co-evolutionary relationship in S. scabiei. These results provide new insights into understanding the population genetics and evolutionary biology of S. scabiei and therefore a better understanding of controlling its infestation pathways worldwide.  相似文献   

19.
20.
In this study, acute toxicity tests were performed to evaluate the impacts of lead (II) acetate trihydrate and atrazine on aquatic organism using a typical freshwater flea, Daphnia magna. Besides, the proteomic profile of the treated D. magna (LC20) was investigated in the pH range from 3 to 10 using 2-dimensional gel electrophoresis method and then analyzed by the Progenesis software to explore the differentially expressed proteins (DEPs) compared to the control organisms. The results showed that there were 179 DEPs caused by these two toxic compounds. More interestingly, the identified DEPs have been found to be involved in energy metabolism, oxidative stress response, dynamic structure of cytoskeleton filaments and effected by two chemicals in opposite ways: up- and down-regulation. A significant difference of protein expression between the control and the stress-exposed D. magna which confirmed the effect of toxic chemicals has been observed. In summary, the proteomic approach as well as the detailed analysis results were proved to be useful for understanding the novel molecular mechanisms for lead or atrazine induced pathological changes. Moreover, specific DEPs can be used as novel biomarker candidates to detect these heavy metal and pesticide.  相似文献   

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