Detection of the root lesion nematode Pratylenchus penetrans in potato tubers     

Joana Figueiredo  Paulo Vieira  Isabel Abrantes  Ivânia Esteves 《Plant pathology》2021,70(8):1960-1968

The root lesion nematode Pratylenchus penetrans parasitizes a wide range of economically important crops, including potato (Solanum tuberosum). Damage by P. penetrans impacts not only the potato yield but can also reduce the tuber quality. Detailed information on tuber infection by P. penetrans is scarce for most cultivars and molecular detection of nematodes from infected tubers is needed. The objective of this study was to assess tuber symptomatology due to P. penetrans infection in 10 potato cultivars and to provide an accurate molecular methodology for nematode detection using tuber peels. Sprouts of certified potato seed from cultivars Agata, Agria, Camel, Désirée, Dirosso, Kennebec, Laura, Picasso, Royata, and Stemster were planted in 2 L pots, and soil was inoculated with 4 P. penetrans/g of soil. Sixty days after inoculation, tubers were harvested, inspected for lesions, and the number of nematodes/g of potato peel assessed. Observations of tubers with symptoms showed the presence of P. penetrans in superficial layers of peels around the lenticels and injured necrotic tissue. Different nematode stages were detected in tubers of all inoculated cultivars, varying from 4 to 46 nematodes/g of potato peel. Species-specific primers showed suitable sensitivity and reproducibility for the detection of P. penetrans in tuber potato peel samples. The molecular detection of P. penetrans directly from tuber peels can facilitate routine nematode inspections of potato seed tubers or cull potatoes for nematode detection, and prevent further dissemination of this species.  相似文献   

Untersuchungen über die Lokalisierung eines ECBO - Virus in Kälbernierenzellen mit Hilfe fluoreszierender Antikörper     

St. Christov  Vl. Serbezov  Iv. Karadjov 《Zoonoses and public health》1967,14(6):562-568

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Functional restoration of the bursa of Fabricius following in ovo infectious bursal disease vaccination   总被引：1，自引：0，他引：1  

Iván J  Nagy N  Magyar A  Kacskovics I  Mészáros J 《Veterinary immunology and immunopathology》2001,79(3-4):235-248

The primary role of the avian bursa of Fabricius is to provide an essential microenvironment for B-lymphocytes to diversify their immunoglobulin genes by gene hyperconversion. Infectious bursal disease (IBD) vaccination using intermediate plus vaccine strains can temporarily deplete the bursal follicles and interrupt the normal B-cell development, which is generally followed by B-cell repopulation and histological regeneration. To find evidence that functional restoration of the bursa of Fabricius occurs in addition to the histological regeneration, we have analysed the chB1 gene expression, which indicates active bursal B-lymphocytes, and also the surface expression of a carbohydrate structure Lewis(x), a marker which identifies those bursal B-lymphocytes that are undergoing gene hyperconversion. In ovo vaccination with an immune complex vaccine (IBDV-BDA) caused transient bursal destruction in both the SPF and the maternally protected broiler groups with differences evident in the starting time, the severity and the duration of the effect. After the depletion phase, signs of histological regeneration appeared together with chB1- and Lewis(x) expression indicating that B-lymphocytes were functionally active and the bursa of Fabricius was serving again as an efficient primary lymphoid organ providing an appropriate microenvironment for B-cell development.  相似文献   

Long-term study of the reproductive timing of the Neotropical catfish Iheringichthys labrosus (Lütken, 1874): Influence of temperature and river discharge     

Nicolás Vidal  Franco Teixeira de Mello  Iván González-Bergonzoni  Anahí López-Rodríguez  Giancarlo Tesitore  Joaquín Pais  Samanta Stebniki  Ivana Silva  Alejandro D’Anatro 《Ecology of Freshwater Fish》2020,29(2):334-345

Unravelling the effect of climate variability on species biology has been one of the main goals of ecological studies. Environmental factors such as river discharge and temperature have being proposed as triggers of reproductive cycle in fish. In temperate climates, fish reproduction is affected mainly by temperature, while is influenced by flood pulses in large tropical rivers. We evaluated the influence of temperature and river discharge as triggers of Iheringichthys labrosus’ reproduction. We studied the following reproductive variables: gonadosomatic index (GSI), hepatosomatic index (HSI) and condition factor (K). Females of I. labrosus were examined in a time series of ten years along three sites located in Lower Uruguay River at the beginning (last week of November-first week of December, spring) and by the end of the reproductive period (middle-end of April, autumn). Generalised linear models detected a positive effect of mean winter temperature and site on the spring mature female GSI. Site was significant in addition to the interaction between temperature and site. Moreover, the effect of winter temperature was stronger than water discharge in triggering reproductive timing of I. labrosus, contrary to the model proposed for other species in tropical systems. Additionally, a literature review suggested a latitudinal gradient on reproduction, occurring earlier and prolonged with decreasing latitude (and increasing temperature). In this study, we stated the effect of temperature on the life history in a Neotropical fish using a multifaceted approach, particularly important in the current context of global climate warming.  相似文献   

Exploring overlooked components of remote South-east Pacific oceanic islands: Larval and macrobenthic assemblages in reef habitats with distinct underwater soundscapes     

Sergio A. Carrasco  Macarena Bravo  Elba Avilés  Paula Ruíz  Alfio Yori  Iván A. Hinojosa 《水产资源保护:海洋与淡水生态系统》2021,31(2):273-289

1. Identifying the diverse assemblage of species inhabiting rocky and coral reef habitats in isolated oceanic environments, and the important sound cues emitted from the reef, are crucial components to understand how species locate suitable habitats for the completion of their life-cycle and, thus, the functioning of these vulnerable ecosystems.
2. Recent field information suggests that the majority of reef biodiversity comprises small cryptic invertebrates; however, knowledge on these small components is extremely scarce.
3. The present study used light attraction methods to explore the diversity of larval, post-larval and macrobenthic cryptic fauna, and hydrophones to characterize the natural soundscape of rocky and coral reef habitats at the Robinson Crusoe island (Juan Fernandez Archipelago; 33°38′S, 78°50′W), and Rapa Nui (Easter Island; 27°7′S, 109°21′W), respectively.
4. Pelagic collections found important site-specific patterns and identified two main species assemblages: early-life stages (e.g. eggs, larval and juvenile stages of crustaceans, molluscs, and fishes) and emerging macrobenthos (e.g. demersal zooplankton such as peracarid crustaceans, ostracods, copepods, and polychaetes), with the latter contributing between 73 and 98% to the total catches.
5. The soundscape records showed marked differences among sites and seasons at Robinson Crusoe island, with variable differences found between day and night. However, at Rapa Nui, there were no differences between sites, but the ambient sound was higher at night possibly due to higher snapping shrimp activity.
6. This information highlights the importance of considering small-scale (site-to-site) patterns when evaluating overlooked components of diversity (i.e. biological or acoustic) in oceanic habitats, and provides the basis for understanding the importance of natural noise in the settlement of most reef-associated species, crucial features for the conservation of these remote and vulnerable ecosystems.

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Analysis of ochratoxin a in coffee by solid-phase cleanup and narrow-bore liquid chromatography-fluorescence detector-mass spectrometry     

Ventura M  Vallejos C  Anaya IA  Broto-Puig F  Agut M  Comellas L 《Journal of agricultural and food chemistry》2003,51(26):7564-7567

A method for the analysis of ochratoxin A (OTA) in green and roasted coffee has been developed. OTA was extracted from coffee with 1% NaHCO(3), and the extract was filtered and purified by solid-phase cleanup using a polymeric column that exhibits reversed-phase and anion-exchange functionalities. OTA was analyzed on a narrow-bore reversed-phase C(18) HPLC column with acetonitrile/water (0.1% formic acid) (40:60) as mobile phase and quantified with a fluorescence detector. The presence of OTA in coffee was confirmed by single-quadruple mass spectrometry using an electrospray ionization source. The method has been validated, obtaining a recovery of 82.5% and a detection limit of 0.1 ng/g. It has been applied to 20 coffee samples from various countries and different manufacturers with no detection of OTA.  相似文献   

Settlement of mycobacteria in aluminum hydroxide-induced cutaneous granuloma of cattle     

G Lami  A Kardeván  T S Iványi  S G?nye  S Tuboly 《Acta veterinaria Academiae Scientiarum Hungaricae》1970,20(1):91-102

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Geographical assessment of body measurements and qualitative traits in West African cattle     

Amadou Traoré  Delphin Oloronto Koudandé  Iván Fernández  Albert Soudré  Víctor Granda  Isabel Álvarez  Siaka Diarra  Fousseyni Diarra  Adama Kaboré  Moumouni Sanou  Hamidou Hamadou Tamboura  Félix Goyache 《Tropical animal health and production》2015,47(8):1505-1513

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Identification of a third feline Demodex species through partial sequencing of the 16S rDNA and frequency of Demodex species in 74 cats using a PCR assay          下载免费PDF全文

Diana Ferreira  Natalia Sastre  Iván Ravera  Laura Altet  Olga Francino  Mar Bardagí  Lluís Ferrer 《Veterinary dermatology》2015,26(4):239-e53

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Variability in sesquiterpene lactones from the leaves of yacon (Smallanthus sonchifolius) accessions of different geographic origin     

María Inés Mercado  María Victoria Coll Aráoz  Iván Manrique  Alfredo Grau  César A. N. Catalán 《Genetic Resources and Crop Evolution》2014,61(6):1209-1217

The sesquiterpene lactones (STLs) content of glandular trichomes from the leaves of twenty-five yacon (Smallanthus sonchifolius, Asteraceae) accessions, obtained along a latitudinal gradient from Ecuador to northwest Argentina, was characterized by gas chromatography/mass spectroscopy (GC/MS). While accessions from Ecuador, Bolivia and Argentina proved to be very chemoconsistent, significant variation was found in quantitative composition of STLs from accessions in central Peru, the probable region of origin for the species.  相似文献