Molecular characterization of a rotaviruslike virus isolated from striped bass (Morone saxatilis).

The characteristics of a rotaviruslike (SBR) virus isolated from striped bass (Morone saxatilis) were examined following purification of viruses from infected cell cultures. Virions had a double-layered capsid of icosahedral symmetry and a diameter of 75 nm. Purified viruses contained five polypeptides ranging in molecular mass from 130 to 35 kDa. None of the structural proteins were glycosylated. Treatment with EDTA did not remove the outer capsid. By using enzymes and a chaotropic agent, it was shown that VP5 was the most external polypeptide. The genome of SBR virus was composed of 11 segments of double-stranded RNA (dsRNA). The electrophoretic pattern of the dsRNA of SBR virus was different from that of reovirus type 1 (Lang) and rotavirus (SA11) dsRNA. The SBR virus was compared with reovirus type 1 and SA11 virus by RNA-RNA blot hybridization. There was no cross-hybridization between any of the genome segments of the SBR, reovirus type 1, or SA11 viruses. Antigenic comparison of SBR virus and SA11 virus by cross-immunoprecipitation and cross-immunofluorescence tests did not show any relationship. These results suggest that SBR virus could represent a new genus within the family Reoviridae.     

Seed transmission of turnip yellow mosaic virus in winter turnip and winter oilseed rapes

This is the first record of seed transmission of turnip yellow mosaic virus (TYMV) in oilseed and turnip rapes. The seed transmission of TYMV in a naturally infected winter turnip rape (Brassica napus var. silvestris) cultivar Perko PVH was investigated. By ELISA 1.6%, 3.2% and 8.3% seed transmission of the virus was found in seed of plants from three localities. The proportion of infected seeds produced by artificially infected plants of winter oilseed rape (Brassica napus ssp. oleifera) and winter turnip rape cultivars was determined. The virus transmission rate, expressed as the proportion of virus-infected plants which germinated from the seed was for the oilseed rape cvs Jet Neuf 0.1%, Solida 0.4%, Silesia 0.8%, Darmor 1.2%, SL-507 0.2%, SL-509 0.0% and for the winter turnip rape cv. Perko 1.5%. ELISA cannot be used in direct tests on bulk seed lots to estimate proportion of infected seed, but must be used on germinated seedlings.     

Aspects of hadrosaurian cranial anatomy

Supraorbital bones in Saurolophus angustirostris are described, and their presence in all hadrosaurs is suggested. Frontal-nasal and premaxillar-nasal fontanellae are distinguished in hadrosaurs; their presence is explained as connected with growth and considered to he responsible for the variability of crest structures. New data indicating the presence of a cartilaginous diverticulum nasi within the circumnarial depression in Saurobphus ongustirostris are presented. A physiological (respiratory and/or thermoregulatory) function of the nasal diverticulum is proposed.     

European checkerspots (Melitaeini: Lepidoptera,Nymphalidae) are not aposematic – the point of view of great tits (Parus major)

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Multiplex panels of polymorphic microsatellite loci for two cryptic bat species of the genus Pipistrellus,developed by cross‐species amplification within the family Vespertilionidae

The paper presents multiplex panels of polymorphic microsatellites for two closely related cryptic species Pipistrellus pipistrellus and Pipistrellus pygmaeus. We tested the cross‐species amplification of 34 microsatellite loci, originally developed for five vespertilionid bat species. Ten and nine polymorphic loci in P. pipistrellus (mean number of alleles per locus = 10.5) and P. pygmaeus (8.1), respectively, in three multiplex polymerase chain reactions per species were amplified. All loci can be analysed in a single fragment analysis and can be used as markers to the study of evolution and the ecology of structured populations of socially living bats.