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Leaves of Fragaria ananassa Duch. cv. Redgauntlet with mottle and mild dwarf symptoms were grafted onto F. vesca indicator clones. The youngest leaves developed specific vein banding pattern located preferentially on secondary vei...
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Leaves of Fragaria ananassa Duch. cv. Redgauntlet with mottle and mild dwarf symptoms were grafted onto F. vesca indicator clones. The youngest leaves developed specific vein banding pattern located preferentially on secondary veins near the edge of the leaves. Electron microscopy of ultrathin sections and negatively stained purified virus preparations from symptom-bearing strawberry leaves revealed presence of different-sized isometric virions. Particles of about 50 nm and 23 nm in diameter were identified as strawberry vein banding virus (SVBV) and tobacco necrosis virus (TNV) D strain. Based on results of electron microscopy, DNA hybridization, enzyme-linked immunosorbent assay (ELISA), and DNA sequencing we propose that the anomalous "leaf edge vein banding" symptoms are caused by a mixed virus infection with SVBV and other viruses such as TNV.
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Daphne shrubs with light green rings and mosaic on leaves contained flexuous filamentous virions (696 x 13 nm) and cylindrical inclusions typical of the subdivision III of Edwardson's classification for inclusions induced by membe...
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Daphne shrubs with light green rings and mosaic on leaves contained flexuous filamentous virions (696 x 13 nm) and cylindrical inclusions typical of the subdivision III of Edwardson's classification for inclusions induced by members of the family Potyviridae. Decoration tests using antisera to 67 potyviruses revealed distant serological relations among chilli veinal mottle virus, Colombian datura virus, papaya ringspot virus, tobacco vein mottling virus and yam mosaic virus. The 3' terminal region of the virus genome was amplified by RT-PCR using primers specific for cloned and sequenced members of the family Potyviridae. The most similar sequences in the GenBank were those of isolates of wild potato mosaic virus (WPMV) and yam mild mosaic virus (YMMV), originating from Peru and Guadeloupe, respectively. The new sequence had 63.2% and 61.9% nucleotide identity to WPMV and YMMV in the coat protein gene. The results suggest that the Czech isolate from daphne should be regarded as a new member of the genus Potyvirus. The name daphne mosaic virus (DapMV) is suggested for this virus.
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Since 1938, when the first observation of a virus-like disease in daphne was recorded , about 15 different viruses have been found in different Daphne species. Among them, two poty viruses have been detected: daphne Y virus in New...
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Since 1938, when the first observation of a virus-like disease in daphne was recorded , about 15 different viruses have been found in different Daphne species. Among them, two poty viruses have been detected: daphne Y virus in New Zealand, with a particle length of 733 nm , and a second virus, also named daphne Y virus, in Germany, with particles of 750 nm in length and serologically related to turnip mosaic virus . The filamentous virus found in the Czech Republic has particles of modal length equal to 696 nm and induces the formation of inclusion bodies that are identical to those of the German isolate, but it is not mechanically transmissible to Chenopodium quinoa and C amaranticolor, in contrast to the German potyvirus. We named the Czech virus Daphne mosaic virus (DapMV), characterised it thoroughly, and based on the nucleotide sequence of the coat protein (CP) gene, proposed it to be a member of a new species of the genus Potyvirus . Here, we report the complete sequence of DapMV and its sequencerelationships.
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The 3'-terminal part of RNA1 genome segment of Radish mosaic virus (RaMV) including complete RNA polymerase gene was sequenced. The 207 amino acids long polymerase is matured from a polyprotein precursor by cleavage at putative Q/...
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The 3'-terminal part of RNA1 genome segment of Radish mosaic virus (RaMV) including complete RNA polymerase gene was sequenced. The 207 amino acids long polymerase is matured from a polyprotein precursor by cleavage at putative Q/H site by viral protease. The alignment of available amino acid sequences of RNA polymerase genes of comoviruses revealed a closest (55%) identity of RaMV to Red clover mottle virus (RCMV).
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The complete mitochondrial genome of the ascomycete fungus Phomopsis longicolla was sequenced using lllumina HiSeq platform. It consists of 53,439 bp with high (65.6%) A + T content and includes 14 conserved protein subunits of th...
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The complete mitochondrial genome of the ascomycete fungus Phomopsis longicolla was sequenced using lllumina HiSeq platform. It consists of 53,439 bp with high (65.6%) A + T content and includes 14 conserved protein subunits of the mitochondrial oxidative phosphorylation system, two ribosomal RNAs and 25 tRNA genes. To our knowledge, this is the first complete mitochondrial genome of the Diaporthales member.
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Inter-simple sequence repeat (ISSR)-polymerase chain reaction (PCR) polymorphism was generated to provide useful markers for assessment of genetic diversity within flax germplasm collections.We used nine previously selected anchor...
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Inter-simple sequence repeat (ISSR)-polymerase chain reaction (PCR) polymorphism was generated to provide useful markers for assessment of genetic diversity within flax germplasm collections.We used nine previously selected anchored ISSR primers for fingerprinting of 53 flax cultivars or genotypes and obtained 62 scorable bands,from which 45 bands (72.6%) were polymorphic.An efficient separation of 53 flax accessions into four groups and eight subgroups was achieved using unweighted pair group method with arithmetic means (UPGMA) clustering procedure based on genetic similarity expressed by the Jaccard similarity coefficient (JSC).Clustering procedure within both groups and subgroups successfully produced smaller homogenous clusters,whereas clustering between the main four groups of flax accessions displayed only a continuous decrease of similarity with a weak clustering effect.Statistical significance of grouping and subgrouping within a cluster dendrogram was estimated by calculation of the error flag and cophenetic correlation parameter for each branch.Principal coordinates (PCO) analysis mostly confirmed the separation by UPGMA clustering.We observed a statistically significant correlation between the number of total vs polymorphic bands in ISSR patterns.A one-way analysis of variance (ANOVA) test confirmed statistically significant differences in the average thousand seed mass (TSM) between eight subclusters of flax accessions from an ISSR-PCR-based UPGMA dendrogram,which indicate statistical correlation between flax ISSR polymorphism (the structure of ISSR-based clustering) TSM.
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We revealed four statistically significant correlations related to inter-simple-sequence repeat (ISSR) patterns: (1) between thermodynamic free energy DELTAG~° of ISSR primer sequence and PCR reamplification intensity (dA_i),(2) ...
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We revealed four statistically significant correlations related to inter-simple-sequence repeat (ISSR) patterns: (1) between thermodynamic free energy DELTAG~° of ISSR primer sequence and PCR reamplification intensity (dA_i),(2) between free energy DELTAG~° of ISSR primer sequence and PIC coefficient quantifying the polymorphism of ISSR patterns,(3) and (4) between free energy DELTAG~° of anchor sequence of primer and the number of total,and polymorphic bands in ISSR patterns,respectively.Methodological recommendations for effective ISSR primer design were inferred based on revealed correlations.In particular,free energy of ISSR primer sequence is recommended to be DELTAG~°>160 kJ/mol of interaction and free energy of flanking anchor sequence in primer to be around DELTAG~°=28 kJ/mol of interaction to produce ISSR patterns displaying maximum polymorphism of flax germplasm.
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Spatial distribution of ground beetles and moths in the isolated Central European Mrtvy luh bog was analyzed. The most stenotopic tyrphobiontic species (relicts restricted to the peat bog) of ground beetles (Coleoptera: Carabidae)...
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Spatial distribution of ground beetles and moths in the isolated Central European Mrtvy luh bog was analyzed. The most stenotopic tyrphobiontic species (relicts restricted to the peat bog) of ground beetles (Coleoptera: Carabidae) and moths (Lepidoptera) are distributed according to a distinct ecological gradient between the bog margin (lagg) and the bog centre. The degree of habitat preference between the bog margin and centre is taxonomically specific and significant. A list of stenotopic species of high conservation value is given. Several tyrphobiontic species occur in the treeless bog centre only. The tyrphophilous and tyrphoneutral species are distributed in the peat bog mostly randomly, some of such species prefer bog margins. The migratory highly opportunistic moths from habitats outside the bog usually cross the treeless centre. Most of the ubiquitous tyrphoneutral and migratory moths represent the faunal component, which is a very temporary phenomenon only, not associated with the peat bog permanently. The conservation of insect biodiversity associated with isolated peat bogs depends on complete preservation of the edaphic ecological conditions of the fragile paleorefugial habitat island and its spatial structure.
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Specific pathogen-free (SPF) rabbits were inoculated with oocysts of an original strain (OS) of Eimeria piriformis and the first newly developed oocysts recovered from the intestine were used for infection of other rabbits. The pr...
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Specific pathogen-free (SPF) rabbits were inoculated with oocysts of an original strain (OS) of Eimeria piriformis and the first newly developed oocysts recovered from the intestine were used for infection of other rabbits. The prepatent period (PP) was shortened after 12 passages from 194 to 170 hours and remained stable after 5 passages without any selection pressure. Oocysts of the precocious line (PL) exhibited peculiar morphology. Besides refractile bodies (RB) within sporozoites, one huge RB joined with a residual body was present inside each sporocyst. The parasite developed in the proximal colon and, to a lesser extent, in other parts of the large intestine. All stages were seen in the epithelium of crypts. In OS, four asexual generations preceded gamogony and, like in other rabbit coccidia, two types of meronts were observed: meronts of type A that develop into polynucleate merozoite, in which endomerogony takes place, and meronts of the type B that form uninucleate merozoites. The endogenous development of PL was identical with that of OS except for the last merogony which was absent. This resulted in earlier appearance of gamogony and shortening of PP. These observations of the life cycle of E. piriformis substantially improve on its description made 50-60 years ago.
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