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1.
The phylogenetic relationships and molecular differentiation of three species of angiostrongylid nematodes (Angiostrongylus cantonensis, Angiostrongylus costaricensis and Angiostrongylus malaysiensis) were studied using the AC primers for a 66-kDa protein gene of A. cantonensis. The AC primers successfully amplified the genomic DNA of these angiostrongylid nematodes. No amplification was detected for the DNA of Ascaris lumbricoides, Ascaris suum, Anisakis simplex, Gnathostoma spinigerum, Toxocara canis, and Trichinella spiralis. The maximum-parsimony (MP) consensus tree and the maximum-likelihood (ML) tree both showed that the Angiostrongylus taxa could be divided into two major clades - Clade 1 (A. costaricensis) and Clade 2 (A. cantonensis and A. malaysiensis) with a full support bootstrap value. A. costaricensis is the most distant taxon. A. cantonensis is a sister group to A. malaysiensis; these two taxa (species) are clearly separated. There is no clear distinction between the A. cantonensis samples from four different geographical localities (Thailand, China, Japan and Hawaii); only some of the samples are grouped ranging from no support or low support to moderate support of bootstrap values. The published nucleotide sequences of A. cantonensis adult-specific native 66 kDa protein mRNA, clone L5-400 from Taiwan (U17585) appear to be very distant from the A. cantonensis samples from Thailand, China, Japan and Hawaii, with the uncorrected p-distance values ranging from 26.87% to 29.92%.  相似文献   

2.
This study aimed to assess physicochemical and microbiological properties of fresh spent mushroom substrates (SMSs) – without post-crop heat treatment – from Agaricus subrufescens and Lentinula edodes production to optimize the use of these residues in the soil enrichment for lettuce growth promotion and soil remediation. Organic matter and C content of both SMSs were high. Fresh A. subrufescens SMS was a good source of N, P and K. On the other hand, L. edodes SMS presented a lower concentration of these nutrients and a high level of immaturity. Both SMSs presented high electric conductivity values (2.5–3.4 mS/cm). Microbiological analysis, based upon enumeration of culturable bacteria (thermophilic and mesophilic) and fungi, and also evolution of CO2, showed that SMSs played higher microbial diversity than soil control. Laccase activity from A. subrufescens SMS tended to remain constant during a 2-month period, while L. edodes SMS presented low laccase activity throughout the same period. Agaricus subrufescens and L. edodes were able to grow on a PDA (Potato Dextrose Agar) media supplemented with different concentrations of atrazine (1–50 μg/ml), degraded the herbicide, attaining rates of 35% and 26%, respectively. On experiments of lettuce growth promotion using a soil-based potting media with different SMS rates, 5% and 10% (dw) rates of A. subrufescens SMS resulted in higher lettuce aerial dry weights than the rates of 25% and 40%, the chemical fertilization (NPK) and the control (soil). At 10% supplementation, lettuce aerial dry weight increased 2.2 and 1.3 times compared to the control and the NPK treatment, respectively. Protein content increased along with SMS rates. Fresh A. subrufescens SMS was an excellent supplement for lettuce growth promotion and showed potential for remediation of biocides possibly due to improved microbial diversity and enzymatic activity. Fresh L. edodes SMS was not a good fertilizer, at least under the conditions tested. However, microbiological analysis showed that promising results may be achieved when using fresh L. edodes SMS for soil remediation.  相似文献   

3.
The origin of Hordelymus genome has been debated for years, and no consensus conclusion was reached. In this study, we sequenced and analyzed the RPB2 (RNA polymerase subunit II) gene from Hordelymus europaeus (L.) Harz, and its potential diploid ancestor species those were suggested in previous studies. The focus of this study was to examine the phylogenetic relationship of Hordelymus genomes with its potential donor Hordeum, Psathyrostachys, and Taeniatherum species. Two distinguishable copies of sequences were obtained from H. europaeus. The obvious difference between the two copies of sequences is a 24 bp indel (insertion/deletion). Phylogenetic analysis showed a strong affinity between Hordeum genome and Hordelymus with 85% bootstrap support. These results suggested that one genome in tetraploid H. europaeus closely related to the genome in Hordeum species. Another genome in H. europaeus is sister to the genomes in Triticeae species examined here, which corresponds well with the recently published EF-G data. No obvious relationship was found between Hordelymus and either Ta genome donor, Taeniatherum caput-medusae or Ns genome donor, Psathyrostachys juncea. Our data does not support the presence of Ta and Ns genome in H. europaeus, and further confirms that H. europaeus is allopolyploid.  相似文献   

4.
Varroa destructor mite is currently the most serious threat to the world bee industry. Differences in mite tolerance are reported between two honey bee species Apis mellifera and Apis cerana. Differential gene expression of two honey bee species induced by V. destructor infection was investigated by constructing two suppression subtractive hybridization (SSH) libraries, as first steps toward elucidating molecular mechanisms of Varroa tolerance. From the SSH libraries, we obtained 289 high quality sequences which clustered into 132 unique sequences grouped in 26 contigs and 106 singlets where 49 consisted in A. cerana subtracted library and 83 in A. mellifera. Using BLAST, we found that 85% sequences had counterpart known genes whereas 15% were undescribed. A Gene Ontology analysis classified 51 unique sequences into different functional categories. Eight of these differentially expressed genes, representative of different regulation patterns, were confirmed by qRT-PCR. Upon the mite induction, the differentially expressed genes from both bee species were different, except hex 110 gene, which was up-regulated in A. cerana but down-regulated in A. mellifera, and Npy-r gene, which was down-regulated in both species. In general, most of the differential expression genes were involved in metabolic processes and nerve signaling. The results provide information on the molecular response of these two bee species to Varroa infection.  相似文献   

5.
In the autumn/winter breeding polychaetes, Arenicola marina and A. defodiens, spawning can be advanced or delayed by a number of months through temperature manipulation of the adults. However, this manipulation may have significant consequences for fertilization rates and embryo developmental success and so in vitro fertilizations were performed to assess the impact of manipulation. Firstly, we used oocytes and sperm obtained from advanced or delayed individuals. For both species, using gametes from 4 weeks advanced individuals did not result in a significant reduction in development, however, gametes from individuals advanced (A. marina only) or delayed by 8 weeks resulted in significantly fewer embryos developing normally. Reciprocal crosses of temperature-manipulated A. marina gametes (from 4 weeks advanced and 4 weeks delayed individuals) with those at the natural spawning time confirmed that the reduction in developmental success in both was attributable to the oocytes. After 5 h post-fertilization, the majority of oocytes from advanced individuals had fertilized, but by 24 h most were abnormal. For fertilizations with gametes from delayed individuals, nearly 100% of the embryos were developing normally after 24 h, but after 144 h significantly more were abnormal in crosses involving oocytes from delayed females. Although both species have reproductive plasticity to extend their breeding season, the significant reduction in the numbers of competent larvae produced as the spawning is delayed or advanced further may be a significant bottleneck in aquaculture and it may also have considerable implications for the long-term reproductive success of a population in response to environmental change.Sympatric populations of the species exist in many locations and the inherent variability in the breeding seasons could allow spawning times to overlap. Artificially delaying A. marina individuals enabled fertilizations to be performed with A. defodiens at the natural spawning time in the laboratory. Both conspecific fertilizations produced 100% trochophore larvae after 120 h, but A. defodiens oocytes failed to fertilize after incubation with A. marina sperm, in comparison to the A. marina oocytes incubated with A. defodiens sperm where 40% developed to the trochophore stage. This asymmetric gamete incompatibility may be one of a suite of mechanisms to minimise hybridisation.  相似文献   

6.
7.
The aim of this study was to characterise the genetic variation and molecular relationships of the brown rot polypore, Laetiporus sulphureus s. lat., from Europe, South America, Africa, and Asia, using ITS sequences of the nu-rDNA and by comparing the growth rate in vitro. In a NJ analysis of the sequences of 130 individuals of L. sulphureus s. lat., eight distinct clusters emerged, supported by BS values of 70-100 %. Within each cluster, the ITS rDNA sequence variation was below 3 %. The sequences were also analysed together with Laetiporus sequences available from GenBank. Results demonstrated the possible presence of L. huroniensis in Europe (invalidly named L. montanus) and L. gilbertsonii in South America, and provided more information on the Pan-American and European distribution of one of the clades, currently known in North America as L. sulphureus. L. conifericola formed a separate distinct clade. Moreover, the analysis revealed two unknown Laetiporus taxa in Korea, one in South Africa, and one in Europe. As L. sulphureus is described from Europe (France), and we show that more than one taxon exist here, it is presently not possible to define L. sulphureus s. str. Certain biological differences between some of the clades (in vitro growth rates, chemical composition, and pigmentation) were demonstrated and discussed.  相似文献   

8.
A phylogenetic analysis of Bambusa and allies based on the plastid DNA non-coding regions rps16-trnQ, trnC-rpoB, trnH-psbA and trnD-T, and a partial nuclear GBSSI gene, was carried out. This included representatives from all four Bambusa subgenera (including type species), a group of segregate Southeast Asian genera distinctive by their climbing–scrambling culms (Dinochloa, Holttumochloa, Kinabaluchloa, Maclurochloa, Soejatmia, Sphaerobambos), and two other Bambusinae genera (Dendrocalamus, Gigantochloa). The results do not support the present subgeneric classification of Bambusa. The climbing Southeast Asian genera, all of which include species previously placed in Bambusa, are distinct from the “core Bambusa group” (type species and alliance) and the Bambusa complex generally.  相似文献   

9.
Lindernia procumbens and L. dubia are common annual weeds in flooded rice fields of Japan. Two subspecies of L. dubia, subsp. major and subsp. dubia, are usually recognized in Japan but they are both regarded as synonyms of L. dubia elsewhere. In a cluster analysis based on AFLP, most L. dubia subsp. major formed a separate cluster from L. dubia subsp. dubia although 11% of haplotypes classified using AFLP were not coincident with classification using the shape of leaf bases, which is the commonly used identification trait. Artificial F1 plants between L. procumbens and L. dubia subsp. major, and between L. procumbens and L. dubia subsp. dubia did not produce seed. Forty percent of capsules produced by F1 plants from these two subspecies were slimmer and 80% pollen were sterile in slimmer capsules. However, seed number of most F1 capsules was not different from that of self-fertilized plants, suggesting that there was no complete reproductive isolation between the subspecies. Natural hybridization of these subspecies may have occurred but we are not aware of it because F1 plants are rare and F2 plants are indistinguishable from these subspecies.  相似文献   

10.
Bioluminescence is well known among white-spored species of Basidiomycota including several species of the white-rot wood decay genus Armillaria. Previous work demonstrated consistent differences among A. gallica, A. mellea, and A. tabescens in luminescence magnitude and in luminescence expression relative to environmental stimuli. In the present studies, temporal fluctuations in mycelial luminescence were quantitatively characterized using genets matched for geographical location. All genets derived from rhizomorphs or basdiomata were constitutively luminescent while six of 13 genets originating from mycelial fans were inconsistently luminescent. Using time series of 1000 consecutive measurements over 800 ms intervals, fluctuation patterns had significantly quantifiable structure and were not simply ‘white noise’. Fluctuation patterns were qualitatively similar with alternating periods of rapid fluctuation and relative stability, regardless of luminescence magnitude. Anomalous spikes or shifts in luminescence were recorded for several genets suggesting further work to identify the transient stimuli which elicited these altered luminescence patterns.  相似文献   

11.
组蛋白作为核小体的基本组分,是染色质的结构和功能必需的。组蛋白的变体和修饰共同参与染色质修饰及基因的表达调控。真核生物细胞中的5种组蛋白在进化中高度保守,然而纤毛虫的组蛋白H4与其他真核生物相比有较大的差异。本实验应用PCR技术从八肋游仆虫(Euplotes octocarinatus)中获得了2种组蛋白H4基因,分别为H4A和H4B,GenBank登录号为:JN715068和JN715069。序列分析表明,H4A基因开放阅读框324 bp,预测编码107个氨基酸,分子量为11.6 ku,等电点为10.99。而H4B基因编码框384 bp,编码127个氨基酸,分子量为14.4 ku,等电点为9.93。Blast结果显示,H4A序列与其他生物中H4的一致性相对较高,达81%~94%,而H4B的一致性为36%~70%。H4A和H4B的一致性仅为44.7%。实时荧光定量PCR表明,H4A的转录本高于H4B。结果提示:在进化过程中八肋游仆虫可能进化出特殊的组蛋白H4基因,不同的组蛋白H4可能发挥不同的功能。  相似文献   

12.
As part of studies of metabolites from fungi common in the built environment in Canadian homes, we investigated metabolites from strains of three Eurotium species, namely E. herbariorum, E. amstelodami, and E. rubrum as well as a number of isolates provisionally identified as Aspergillus ustus. The latter have been recently assigned as the new species A. insuetus and A. calidoustus. E. amstelodami produced neoechinulin A and neoechinulin B, epiheveadride, flavoglaucin, auroglaucin, and isotetrahydroauroglaucin as major metabolites. Minor metabolites included echinulin, preechinulin and neoechinulin E. E. rubrum produced all of these metabolites, but epiheveadride was detected as a minor metabolite. E. herbariorum produced cladosporin as a major metabolite, in addition to those found in E. amstelodami. This species also produced questin and neoechinulin E as minor metabolites. This is the first report of epiheveadride occurring as a natural product, and the first nonadride isolated from Eurotium species. Unlike strains from mainly infection-related samples, largely from Europe, neither ophiobolins G and H nor austins were detected in the Canadian strains of A. insuetus and A. calidoustus tested, all of which had been reported from the latter species. TMC-120 A, B, C and a sesquiterpene drimane are reported with certainty for the first time from indoor isolates, as well as two novel related methyl isoquinoline alkaloids.  相似文献   

13.
The goal of this study was to examine the fatty acid (FA) profile of two Artemia species, A. persimilis (Argentina) and A. franciscana (Great Salt Lake,Utah; USA) in coexistence at mesocosm scale. The experiment was carried out to 1) evaluate putative differences in the fatty acid composition of both species while they share resources and 2) to investigate the causes of such differences. Although the coexistence of these species in nature has not yet been observed, it remains possible that this situation may arise in the future mainly due to the invasive ability of A. franciscana. FA analyses were performed on individuals as well as on pooled biomasses of each species, and integrated in multivariate principal components analysis (PCA). Comparison of the relative abundance of FA between the two species revealed that interspecific differences in FA composition are greater than intraspecific variability. Higher percentages of unsaturation were found in the fatty acids of A. persimilis compared to A. franciscana, demonstrating that aside from a high phenotypic effect of diet on the FA composition of the animals, a species-specific genotypic effect should not be discarded.  相似文献   

14.
Phylogenetic relationships among the true finches (Fringillidae) have been confounded by the recurrence of similar plumage patterns and use of similar feeding niches. Using a dense taxon sampling and a combination of nuclear and mitochondrial sequences we reconstructed a well resolved and strongly supported phylogenetic hypothesis for this family. We identified three well supported, subfamily level clades: the Holoarctic genus Fringilla (subfamly Fringillinae), the Neotropical Euphonia and Chlorophonia (subfamily Euphoniinae), and the more widespread subfamily Carduelinae for the remaining taxa. Although usually separated in a different family-group taxon (Drepanidinae), the Hawaiian honeycreepers are deeply nested within the Carduelinae and sister to a group of Asian Carpodacus. Other new relationships recovered by this analysis include the placement of the extinct Chaunoproctus ferreorostris as sister to some Asian Carpodacus, a clade combining greenfinches (Carduelis chloris and allies), Rhodospiza and Rhynchostruthus, and a well-supported clade with the aberrant Callacanthis and Pyrrhoplectes together with Carpodacus rubescens. Although part of the large Carduelis-Serinus complex, the poorly known Serinus estherae forms a distinct lineage without close relatives. The traditionally delimited genera Carduelis, Serinus, Carpodacus, Pinicola and Euphonia are polyphyletic or paraphyletic. Based on our results we propose a revised generic classification of finches and describe a new monotypic genus for Carpodacus rubescens.  相似文献   

15.
The identification of the conventionally accepted species of Clavulina (Cantharellales, Basidiomycota) in Europe (Clavulina amethystina, Clavulina cinerea, Clavulina cristata, and Clavulina rugosa) is often difficult and many specimens are not straightforwardly assignable to any of those four species, which is why some authors have questioned their identity. In order to assess the status of those species, a morphological examination was combined with the molecular analysis of the ITS region. The same six major clades were obtained in the Bayesian and parsimony phylogenetic analyses, and all six clades were well-supported at least by one of the analyses. Morphological characters, such as the overall branching pattern, the presence and intensity of grey colour, the cristation of the apices, and basidiospore size and shape were to various extents correlated with the phylogenetic signal obtained from the ITS region. The congruence between the molecular analyses and morphology, rather than geographical origin, suggests the existence of several species that can be delimited using a combined phylogenetic and morphological species recognition. The analyses revealed that C. cristata and C. rugosa are well-delimited species. In contrast, more than one taxa could be subsumed under the names C. amethystina and C. cinerea, the taxonomical complexity of which is discussed. The ITS region is proved to be adequate to separate phylogenetic species of Clavulina.  相似文献   

16.
The study of the primitive gerbil remains of Pseudomeriones, recovered from the micromammalian sites of Paliambela-B and Monasteri (Latest Miocene, Northern Greece), gives evidence for a new species, which is characterized by its large size and simple molar morphology. A cladistic analysis based on dental characters affiliates this form with P. rhodius and P. pythagorasi and enables an intrageneric phylogenetic scenario.  相似文献   

17.
18.
The ultrastructure of septa and septum-associated septal pore caps are important taxonomic markers in the Agaricomycotina (Basidiomycota, Fungi). The septal pore caps covering the typical basidiomycetous dolipore septum are divided into three main phenotypically recognized morphotypes: vesicular-tubular (including the vesicular, sacculate, tubular, ampulliform, and globular morphotypes), imperforate, and perforate. Until recently, the septal pore cap-type reflected the higher-order relationships within the Agaricomycotina. However, the new classification of Fungi resulted in many changes including revision of existing and addition of new orders. Therefore, the septal pore cap ultrastructure of more than 325 species as reported in literature was related to this new classification. In addition, the septal pore cap ultrastructures of Rickenella fibula and Cantharellus formosus were examined by transmission electron microscopy. Both fungi have dolipore septa associated with perforate septal pore caps. These results combined with data from the literature show that the septal pore cap-type within orders of the Agaricomycotina is generally monomorphic, except for the Cantharellales and Hymenochaetales.It appears from the fungal phylogeny combined with the septal pore cap ultrastructure that the vesicular-tubular and the imperforate type both may have arisen from endoplasmic reticulum. Thereafter, the imperforate type eventually gave rise to the perforate septal pore cap-type.  相似文献   

19.
Dark, septate endophytes (DSE) were isolated from roots and needles of dwarf Picea abies and from roots of Vaccinium spp. growing on a permafrost site in the Jura Mountains in Switzerland. Two of the isolates sporulated after incubation for more than one year at 4 °C. One of them was a hitherto undescribed helotialean ascomycete Phaeomollisia piceae gen. sp. nov., the other was a new species of Phialocephala, P. glacialis sp. nov. Both species are closely related to DSE of the Phialocephala fortinii s. lat.-Acephala applanata species complex (PAC) as revealed by phylogenetic analyses of the ITS and 18S rDNA regions. Morphologically dissimilar fungi, such as Vibrissea and Loramyces species, are phylogenetically also closely linked to the new species and the PAC. Cadophora lagerbergii and C. (Phialophora) botulispora are moved to Phialocephala because Phialocephala dimorphospora and P. repens are the closest relatives. Several Mollisia species were closely related to the new species and the PAC according to ITS sequence comparisons. One DSE from needles of Abies alba and one from shoots of Castanea sativa formed Cystodendron anamorphs in culture. Their identical 18S sequences and almost identical ITS sequences indicated Mollisia species as closest relatives, suggesting that Mollisia species are highly euryoecious.  相似文献   

20.
In this report, a molecular phylogeny based on the plastid gene matK and on the region between the genes trnL and trnF, and a chemical relationship based on the pattern of sesquiterpenes, is proposed for Aristolochia species from southeastern Brazil. We found that Aristolochia is a monophyletic genus and species considered to be derived contain labdanoic acids (LAs) in their leaves. The phenetic relationship recovered with sesquiterpenes did not agree with the phylogenetic relationships for Aristolochia, and three main clusters were recognized, namely, germacrene-D, germacrene-C and Z-caryophyllene groups. The presence of different sesquiterpene structures in species that are phylogenetically closely related may reflect adaptations to avoid predation of herbivores specialized in feeding on Aristolochiaceae plants.  相似文献   

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