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1.
The current work shows the first step in the knowledge on the health status of European storm petrel (Hydrobates pelagicus) colony inhabiting Grosa Island (Murcia, SE Spain). We performed a screening about the bacterial pathogens carried by them (among the infectious agents checked, bacteria of the orders Mollicutes and Chlamydiales, and the genera Salmonella are of main interest) and compare these results with similar works performed in Larus species because most of the breeding colonies of storm petrel share habitats with gull colonies, and these could become pathogen reservoirs to petrels. Our results show the European storm petrels sampled have absence of pathogens of main interest and low levels of opportunistic pathogens. No Mycoplasma species were isolated, and no Chlamydophila psittaci were demonstrated by lipopolysaccharide antigen immunodetection. The commensal bacteria were isolated in higher frequencies than the previous [Staphylococcus epidermidis (5/15), Staphylococcus hominis (2/15) and Staphylococcus aureus (1/15)]. The rate of isolation of Gram-negative was lower than in the previous Gram-positive bacteria [Pasteurella sp. (1/15) and Pseudomonas aeruginosa (1/15)], and no Enterobacteriaceae were isolated. The absence of pathogen carriers on European storm petrel is the main conclusion of this survey; it is an evidence that the bacterial infectious pathogens described in gulls may not be an important selective force on their survival.  相似文献   

2.
Intraplant epizootics of entomopathogens,Beauveria bassiana (Balsamo) Vuillemin, andNosema pyrausta (Paillot) were studied in a corn,Zea mays L., agroecosystem. Egg masses of the European corn borer,Ostrinia nubilalis (Hübner), infected withN. pyrausta were placed on midwhorl-stage corn plants. Conidia ofB. bassiana were applied in an aqueous suspension. Frass from the initial insects remaining within the plants was contaminated with sufficientN. pyrausta spores to infest 80% of the filial generation in each year of a 2-yr study. Viability ofN. pyrausta within the frass was monitored throughout the winter. Potential for impact of this inoculum on the filial generation is discussed. Conidia from cadavers of the European corn borer that were killed by the initial inoculum ofB. bassiana and/or conidia from the initial inoculum ofB. bassiana significantly reduced tunneling by the filial generation of the European corn borer. However, neither the concentration ofB. bassiana nor the age of the larvae exposed toB. bassiana, had any significant (P<.05) effect on tunneling by the 2nd-generation larvae. This paper reports the results of research only. Mention of a pesticide in this paper does not constitute a recommendation for use by the U.S. Department of Agriculture or cooperators, nor does it imply registration under FIFRA as amended.  相似文献   

3.
Indigenous to Europe, the blackberry rust fungus Phragmidium violaceum was introduced to Australia and subsequently appeared in New Zealand, with the most recent authorised introductions to Australia specifically for the biological control of European blackberry. Markers for ‘selective amplification of microsatellite polymorphic loci’ (SAMPL) were developed for studying the population genetics of P. violaceum. Modification of one of the two SAMPL primers with a HaeIII adapter (H) revealed significantly greater levels of genetic variation than primers used to generate AFLPs, the latter revealing little or no variation among 25 Australasian and 19 European isolates of P. violaceum. SAMPL was used to describe genetic variation among these 44 isolates of P. violaceum from 51 loci generated using primer pairs (GACA)4 + H–G and R1 + H–G. The European isolates were more diverse than Australasian isolates, with 37 and 22 % polymorphic loci, respectively. Cluster analysis revealed geographic clades, with Australasian isolates forming one cluster separated from two clusters comprising the European isolates. However, low bootstrap support at these clades suggested that Australian isolates had not differentiated significantly from European isolates since the first record of P. violaceum in Australia in 1984. In general, the results support two hypotheses. First, that the population of P. violaceum in Australia was founded from a subset of individuals originating from Europe. Second, that P. violaceum in New Zealand originated from the Australian population of P. violaceum, probably by wind dispersal of urediniospores across the Tasman Sea. The application of SAMPL markers to the current biological control programme for European blackberry is discussed.  相似文献   

4.
The respective status of the Portuguese oyster, Crassostrea angulata, and the Pacific oyster, Crassostrea gigas, has long been a matter of controversy. Morphological and physiological similarities, homogeneity of allozyme allelic frequencies between populations of the two taxa and the demonstration of hybridization lead most authors to suggest that they should be regrouped within the same species. The risk of introgression and the present expansion of C. gigas aquaculture in Europe raises the question of the need for preservation of C. angulata in Europe, as only a few populations remain. We studied European and Asian populations of C. gigas and C. angulata using microsatellite and mitochondrial DNA markers to estimate their genetic diversity and differentiation. The analysis of genetic distances and the distribution of allelic and haplotype frequencies revealed significant genetic differences between taxa, showing two clusters: (1) C. gigas French and Japanese populations and (2) C. angulata Portuguese and Taiwanese populations. The Asian origin of the Crassostrea angulata taxa is therefore confirmed. Unlike previous studies based on allozymes, significant nuclear genome differences were noted between C. angulata and C. gigas. Despite the presumed history of the introduction of C. angulata into Southern Europe, these populations did not show any significant reduction of variability compared to Taiwanese populations. Any conservation plans for European C. angulata populations should take its non-native origin into account. They represent a valuable genetic resources for European breeding program.  相似文献   

5.
In this note the taxonomic position of the tiny eomyid genus Keramidomys (Hartenberger, 1967) from the Early/Middle Miocene boundary locality of Sandelzhausen in the Bavarian Upper Freshwater Molasse is reexamined. As the chronological dating of the Sandelzhausen fossil site has been modified in the past from formerly the Neogene mammal unit MN6 to now MN5 and thanks to new abundant material this rodent is compared with other European forms. It is shown that the Sandelzhausen eomyid must be called K. thaleri Hugueney & Mein, 1968 on the basis of several morphological dental differences from K. carpathicus Schaub & Zapfe, 1953. This rodent seems to be an immigrant from East Asia into Europe. Even if K. thaleri is known in many European localities, all correlated to MN5, it is always a rare element of European rodent faunas. Differentiation from K. carpathicus is not easy and requires a sufficiently large sample.   相似文献   

6.
European Black Poplar (Populus nigra) is considered a rare and endangered tree species because of severe reduction of its natural riverine habitat and potential hybridisation with the related non-indigenous taxa P. deltoides and P. x canadensis. As it is difficult to distinguish these taxa solely based on their morphology, we applied a PCR-based assay with an easy-to-use and robust molecular marker set (cpDNA trnL-trnF/RsaI RFLP, nDNA win3 and nDNA POPX/MspI RFLP) in order to identify pure P. nigra. Different plant tissues could be used for fast and standardised DNA extraction. The application of the three marker types was tested on a number of different Populus taxa, and they were also used for the verification of pure P. nigra in a sample of 304 putative P. nigra individuals from Switzerland. Cross-checking of the DNA data with those using a traditional allozyme approach resulted in complete agreement. The availability of molecular identification methods is an important prerequisite for the conservation of European Black Poplar, because pure, non-introgressed plant material can then be used in restoration projects of European floodplains.  相似文献   

7.
北京出入境检验检疫局从美国进境旅客携带的石榴中检出欧洲球螋。了解欧洲球螋的基本特性,能为相关部门对其检疫鉴定提供参考依据。对欧洲球螋的相关文献进行了查阅和整理,详细介绍了欧洲球螋的分类地位、分布、形态特征及近似种等信息,我国出入境检验检疫部门对球螋属的截获情况,讨论了欧洲球螋的检疫意义。认为欧洲球螋在我国无分布且具有一定的入侵风险,口岸应对该虫引起足够的重视。  相似文献   

8.
Diseases of Mites   总被引:6,自引:0,他引:6  
An overview is given of studies on diseases of mites. Knowledge of diseases of mites is still fragmentary but in recent years more attention has been paid to acaropathogens, often because of the economic importance of many mite species. Most research on mite pathogens concerns studies on fungal pathogens of eriophyoids and spider mites especially. These fungi often play an important role in the regulation of natural mite populations and are sometimes able to decimate populations of phytophagous mites. Studies are being conducted to develop some of these fungi as commercial acaricides.Virus diseases are known in only a few mites, namely, the citrus red mite and the European red mite. In both cases, non-occluded viruses play an important role in the regulation of mite populations in citrus and peach orchards, respectively, but application of these viruses as biological control agents does not seem feasible. A putative iridovirus has been observed in association with Varroa mites in moribund honeybee colonies. The virus is probably also pathogenic for honeybees and may be transmitted to them through this parasitic mite.Few bacteria have been reported as pathogens of the Acari but in recent years research has been concentrated on intracellular organisms such as Wolbachia that may cause distorted sex ratios in offspring and incompatibility between populations. The role of these organisms in natural populations of spider mites is in particular discussed. The effect of Bacillus thuringiensis on mites is also treated in this review, although its mode of action in arthropods is mainly due to the presence of toxins and it is, therefore, not considered to be a pathogen in the true sense of the word.Microsporidia have been observed in several mite species especially in oribatid mites, although other groups of mites may also be affected. In recent years, Microsporidia infections in Phytoseiidae have received considerable attention, as they are often found in mass rearings of beneficial arthropods. They affect the efficacy of these predators as biological control agent of insect and mite pests. Microsporidia do not seem to have potential for biological control of mites.  相似文献   

9.
DNA contents have been determined cytophotometrically in the three Central European, relatedScilla speciesS. bifolia (2n = 18, 2 x, 1 C = 6.2 pg),S. drunensis (2n = 36, 4 x, 1 C = 12.8 pg), andS. vindobonensis (2n = 18, 2 x, 1 C = 9.4 pg). The tetraploid speciesS. drunensis contains twice as much DNA as the diploidS. bifolia. However, the diploid speciesS. vindobonensis differs in DNA content fromS. bifolia by a factor of about 1.5. This difference is largely due to euchromatic DNA, although the higher DNA content inS. vindobonensis is combined with higher heterochromatin content. The data indicate thatS. bifolia andS. drunensis on the one hand, andS. vindobonensis on the other hand are phyletically well separated. Previous taxonomic conclusions from morphology as well as C-banding are thus corroborated.Evolution ofScilla and Related Genera, V.  相似文献   

10.
Summary Dispersed pituitary cells from male African catfish, Clarias lazera, were fractionated in a density gradient of Percoll. Five fractions were isolated, consisting of about 6, 19, 39, 95 and 83% gonadotrops, respectively. The gonadotrops were identified by their ultrastructural characteristics, by immunocytochemistry, and by measuring their hormone content. After one day in culture, in each fraction the secretion of gonadotropin could be stimulated by a luteinizing hormone-releasing hormone analogue, indicating that the cells had retained their functional integrity. Since the regulatory mechanisms of different cell types from the pituitary have some similarity, purification of the gonadotrops provides a model to study the regulation of gonadotropin secretion.A portion of the results was presented as a poster at the XIIth Conference of the European Society of Comparative Endocrinology, Sheffield, July 31–August 5, 1983  相似文献   

11.
Wild common carp from two lakes and two rivers in Greece were genetically characterized with sequencing analysis of two mitochondrial DNA segments: cytochrome b (1119 bp) and D-loop (646 bp). A total of 9 variable singleton sites and 7 unique haplotypes were detected. A common haplotype was found in three out of the four populations examined, which seems to be the ancestral one and represents the European origin of common carp from Greece. This haplotype could be also justified by the introductions reported with individuals belonging to the Central European race, into many natural habitats in Greece. Limited genetic variation — in Evros and Aliakmonas populations — could be due to bottleneck effects and small effective population sizes, whereas the different haplotypes found in Lake Volvi could represent different common carp stocks. Values of sequence divergence among Greek haplotypes ranged from 0.0006 to 0.0023. The Neighbour-Joining (NJ) phylogenetic tree constructed based on the combined sequences, reveals that the populations of common carp from Greece belong to the European group of populations — which is highly divergent from the South East-Asia cluster — and to the subspecies Cyprinus carpio carpio.  相似文献   

12.
Zhou JF  Wu QJ  Ye YZ  Tong JG 《Genetica》2003,119(1):93-97
Although common carp is the major fish species in Asian and European aquaculture and many domestic varieties have occurred, there is a controversy about the origination of European domestic common carp. Some scientists affirmed that the ancestor of European domestic common carp was Danube River wild common carp, but others considered it might be Asian common carp. For elucidating origination of European domestic common carp, we chose two representative European domestic common carp strains (German mirror carp and Russian scattered scaled mirror carp) and one wild common carp strain of Cyprinus carpio carpio subspecies (Volga River wild common carp) and two Asian common carp strains, the Yangtze River wild common carp (Cyprinus carpio haematopterus) and traditionally domestic Xingguo red common carp, as experimental materials. ND5–ND6 and D-loop segments of mitochondrial DNA were amplified by polymerase chain reaction and analyzed through restriction fragment length polymorphism (RFLP) and sequencing respectively. The results revealed that HaeIII and DdeI digestion patterns of ND5–ND6 segment and sequences of control region were different between European subspecies C. carpio carpio and Asian subspecies C. carpio haematopterus. Phylogenetic analysis showed that German mirror carp and Russian scattered scaled mirror carp belonged to two subspecies, C. carpio carpio and C. carpio haematopterus, respectively. Therefore, there were different ancestors for domestic carp in Europe: German mirror carp was domesticated from European subspecies C. carpio carpio and Russian scattered scaled mirror carp originated from Asian subspecies C. carpio haematopterus.  相似文献   

13.
We examined the Chaetocercus and Lophornis holdings of 21 European, US and South American avian collections. Only skin specimens with exact (to the year) collecting dates and reliable locality data on their labels, which could be checked personally, were analysed. We located 466 Chaetocercus and 373 Lophornis specimens collected between the years 1859 and 1999. The vast majority of these records are old ones, dated between 1880 and 1960: 93% of the Chaetocercus and 82% of the Lophornis study skins. Less than 1% of all specimens was obtained after 1990. Potential explanations for our findings, such as declining population levels of these hummingbird genera, historically changing collecting activities regarding commercial dealers and collecting techniques, and legal collecting restrictions are discussed. Our findings reflect a general trend of decreasing collecting activities worldwide.Communicated by F. Bairlein  相似文献   

14.
Gene content proved to be less than expected in completely sequenced eukaryotic genomes. Moreover, gene number differs only three times between such distant organisms as human and Drosophila. Hence it is likely that the essential functional and structural differences between the two species mostly depend on the regulation of gene activity than on the set and quality of genes themselves. New data demonstrate that changes in chromatin structure play a greater role in the fine gene activity regulation than considered before. R.B. Khesin had foreseen many chromatin functions that only recently came to be recognized. Khesin was interested in genome inconstancy over his last years. A higher content of several important chromosomal proteins was recently revealed in chromatin of transposable genetic elements (TGE). The possible role of TGE in chromatin organization in the nucleus is considered.  相似文献   

15.
Ribosomal DNA sequences were employed to infer relationships among EuropeanPottiaceae. Intragenic spacer I was sequenced for sixTrichostomoideae (Eucladium verticillatum, Pleurochaete squarrosa, Tortella flavovirens, T. nitida, T. tortuosa, Trichostomum brachydontium) and seven taxa from the other European subfamilies included inPottiaceae (Bryoerythrophyllum recurvirostrum, Didymodon vinealis, Microbryum starkeanum, Tortula muralis, Syntrichia ruralis, Weissia controversa andTimmiella cf.barbuloides). Cladistic analysis of sequence data shows close relationships betweenPleurochaete, Tortella andWeissia. Tortella appears to be paraphyletic, as it includesPleurochaete, Weissia andTrichostomum. Weissia, therefore, seems to be better placed inTrichostomoideae than, as traditionally done, inPottioideae. NeitherMerceyoideae norPottioideae appear to be monophyletic sensu stricto, at least within the limits of the taxa in analysis. Within the latter subfamily,Syntrichia is clearly separated fromTortula. These results would suggest that taxonomy inPottiaceae does not depict the pattern of descent, and therefore is in need of revision.  相似文献   

16.
Ooishi  Shigeko 《Hydrobiologia》1994,292(1):89-96
An ascidicolid copepod, Haplostomides hawaiiensis, is described on the basis of females obtained from the compound ascidian Polyclinum constellatum collected in Keehi Lagoon, Honolulu, Hawaii. The features that separate H. hawaiiensis from other species of the genus include an elongate body with dorsal curvature and indistinct tagmosis, and a combination of characters of cephalic appendages (antenna with 2 spines, mandible with 3 setae, maxillule with 7 setae and maxilla with 2 setae) and thoracic appendages (legs 1–4 with 1 seta on protopod and 2 spines and 1 seta on exopod). Haplostomides hawaiiensis appears to be most closely related to H. hibernicus (T. & A. Scott, 1895) which occurs in compound ascidians from European seas. This is the first copepod associate of an ascidian to be reported from Hawaii.  相似文献   

17.
Taiwan is a phytogeographically isolated area, with a rate of ca. 40% endemism in higher plants. In this study, the strong tendency towards genetic isolation and speciation ofBotryobasidium subcoronatum (Basidiomycota) from Taiwan is evaluated in comparison with European specimens. Mating tests amongB. subcoronatum specimens collected in Taiwan and Europe were performed. Mon-mon and di-mon matings confirm different intersterility groups or biological species. The biological species concept was compared with results from morphological comparison and molecular data from mtSSU rDNA and the nuclear ITS2 region. Three intersterility groups have been detected comprising European and Taiwanese strains from temperate and subtropical areas. MtSSU rDNA and the ITS2 rDNA sequences confirm consepecifity ofB. subcoronatum.  相似文献   

18.
Effects of exposure to maize pollen of event Bt176 (cultivar “Navares”) on the larvae of the European common swallowtail (Papilio machaon L.) were studied in the laboratory. First instar larvae were exposed to different pollen densities applied to leaf disks of Pastinaca sativa L. for 48 h. Pollen densities applied in this study were in the range recorded from the field. Larvae which were exposed to higher Bt maize pollen densities consumed more pollen and had a lower survival rate. The LD50 with regard to larvae surviving to adulthood was 13.72 pollen grains consumed by first-instar larva. Uptake of Bt maize pollen led to a reduced plant consumption, to a lower body weight, and to a longer development time of larvae. Effects on pupal weight and duration of the pupal period were present but less pronounced and smaller than effects on larvae. Larvae having consumed Bt-maize pollen as first instars had a lower body weight as adult females and smaller forewings as adult males. We conclude that possible effects of Bt maize on European butterflies and moths must be evaluated more rigorously before Bt maize should be cultivated over large areas.  相似文献   

19.
A molecular phylogenetic analysis of Cynoglottis was performed to evaluate previous hypotheses based on non-molecular evidence concerning the position of this genus within Boraginaceae tribe Boragineae. ITS-5.8S and trnLUAA sequences from the nuclear and chloroplast non-coding genomes were obtained for four Cynoglottis taxa and selected members of the related genera Anchusa, Anchusella, Gastrocotyle, Brunnera and Pentaglottis. Cynoglottis is monophyletic, but neither trnL nor ITS support a close relationship with Brunnera, unlike previously supposed on morphological grounds. Brunnera is, instead, related to the southwestern European monotypic genus Pentaglottis, with which it forms a basal clade. ITS-5.8S sequences show that Anchusa thessala, a southeastern European annual species of Anchusa subg. Buglossellum, is sister to Cynoglottis and that the two taxa form a clade which also includes the Balkan endemic Gastrocotyle macedonica. Species of Anchusa subg. Anchusa form a separate lineage with high bootstrap support, suggesting that this heterogeneous genus is paraphyletic with respect to Cynoglottis. ITS sequences also discriminate between the Balkan-Apenninic diploid C. barrelieri and the Anatolian tetraploid C. chetikiana, albeit with low support. The molecular results are discussed in the light of karyological, morphological and chorological aspects.This work has been supported by M.I.U.R. 40% 2003 and the University of Firenze.  相似文献   

20.
The present review describes the distribution and the function-dependent reactivity pattern of those peptidergic and aminergic components of the neuroendocrine system of hibernating mammals that have been studied by histological, pharmacological and physiological techniques. Particular attention has been paid to the intrinsic connectivity of the peptidergic apparatus and its input systems. Since the reactivity patterns of the neuroendocrine system show remarkable fluctuations in relation to the various stages of hibernation and euthermia, these fluctuations have been analyzed with respect to (1) their causative role in the regulation of hibernation and (2) their secondary response to physiological changes during hibernation. The author's investigations described in this review have mainly been performed in European hedgehogs (Erinaceus europaeus), European and golden hamsters (Cricetus cricetus, Mesocricetus auratus), dormice (Glis glis), and in Richardson's and Columbian ground squirrels (Spermophilus richardsonii, Spermophilus columbianus), by the use of light- and electron-microscopic immunocytochemistry and histochemistry, in situ hybridization, radioimmunoassays and stereotaxically guided application techniques. These experiments were also performed in hypothermic animals. The (partially published) results obtained by the author and his associates are reviewed with reference to the body of evidence found in the recent literature. With respect to their reactivity patterns, several neuropeptide and transmitter systems can be regarded as candidates for control systems of hibernation. Neuronal complexes immunoreactive for endogenous opiates, in particular enkephalin, and also for vaspressin, somatostatin, substance P, corticotropin-releasing factor and serotonin are probably involved in the neuroendocrine control of hibernation.Dedicated to the memory of Dr. Gesa Merker  相似文献   

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