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61.
Eva Syrová Miroslava Palíková Jan Mendel Veronika Seidlová Ivana Papežíková Heike Schmidt-Posthaus Kristina Somerlíková Hana Minářová Lukáš Mareš Ivana Mikulíková Jiří Pikula Jan Mareš 《Journal of fish diseases》2020,43(10):1201-1211
Tetracapsuloides bryosalmonae (Myxozoa: Malacosporea) is the causative agent of proliferative kidney disease (PKD), which affects both wild and farmed salmonid fish. The objective of this study was to outline differences in susceptibility to PKD in different salmonid species, hybrids and breeding lineages. Susceptibility to T. bryosalmonae infection was established based on cumulative mortality, pathological findings and detection of T. bryosalmonae in the kidney using immunohistochemistry and molecular methods. Determination of pure and hybrid individuals of different species in the genus Salvelinus, and dissimilarity of rainbow trout lineages, was performed using traditional polymerase chain reaction (PCR) and microsatellite analyses. Rainbow trout displayed higher disease severity compared with brook trout and Alsatian charr. Moreover, the results indicated differences in infection susceptibility, not only among different salmonid species but also among different lineages of charr and rainbow trout. Our study indicated that some salmonid species and even different lineages of the same species are more suitable for farming under PKD pressure. 相似文献
62.
J. Plavec Ž. Budinšćak I. Križanac D. Škorić X. Foissac M. Šeruga Musić 《Plant pathology》2019,68(1):18-30
Flavescence dorée phytoplasma (FDp) is a quarantine pathogen associated with a severe and epidemic grapevine yellows disease representing a great threat for grapevine cultivation in Europe. An increase in disease spread prompted efforts to identify FDp strains in Croatia. Over 800 samples of grapevine together with presumed reservoir plants and almost 400 samples of Scaphoideus titanus and other potential vectors were collected countrywide and analysed. FDp isolates were characterized by multilocus sequence typing (MLST) of map, secY and uvrB-degV genes in order to determine genetic diversity and structure of FDp populations, and to trace transmission pathways. FD-related phytoplasmas were found in Croatia for the first time in alder, the invasive tree species Ailanthus altissima and leafhopper Phlogotettix cyclops. Phylogenetic analysis revealed the presence of three mapFD strain clusters: mapFD1, mapFD2 and mapFD3, and for the first time in Croatia a case of Palatinate grapevine yellows strain A (PGY-A). In total, 7 different map, 10 secY and 11 uvrB-degV genotypes were detected. The identification of 15 comprehensive FDp genotypes based on MLST suggests separate routes for disease introduction and propagation origins in Croatia. Moreover, high genetic variability of Croatian isolates indicates a complex ecological cycle of FDp involving various hosts. 相似文献
63.
G. V. Nakato P. Christelová E. Were M. Nyine T. A. Coutinho J. Doležel B. Uwimana R. Swennen G. Mahuku 《Plant pathology》2019,68(1):49-59
It is claimed that, with the exception of Musa balbisiana, all banana varieties are susceptible to bacterial wilt caused by Xanthomonas campestris pv. musacearum (Xcm). Despite being resistant to Xcm infection, M. balbisiana is not preferred for breeding because it belongs to the BB genome subgroup, while most edible bananas are of the A genome. To identify potential sources of resistance to Xcm, 72 banana accessions representing the Musa genetic diversity were evaluated in an outdoor confined potted trial. The midribs of the youngest leaf of 3-month-old banana plants were inoculated with 108 CFU mL−1 of Xcm isolate USY13P, and symptom development assessed weekly for 4 months. Results confirmed that M. balbisiana genotypes are indeed resistant to Xcm. Varieties within the Musa acuminata subsp. zebrina (AA) set were further identified as potentially useful sources of Xcm resistance. These findings reveal the potential to develop banana and plantain varieties with tolerance to Xcm. 相似文献
64.
Jurga Motiejūnaitė Gražina Adamonytė Reda Iršėnaitė Sigitas Juzėnas Jonas Kasparavičius Ernestas Kutorga Svetlana Markovskaja 《European Journal of Forest Research》2014,133(4):745-756
The early post-fire development of mycobiota following a crown fire in mountain pine plantations and a surface fire in Scots pine plantations, and in the corresponding unburnt stands in the coastal sand dunes of the Curonian Spit in western Lithuania was investigated. Species numbers in unburnt Pinus mugo and Pinus sylvestris stands showed annual fluctuation, but in the burnt sites, the numbers of fungi increased yearly, especially in the crown fire plots. Both burnt stand types—P. mugo and P. sylvestris—showed strongly significant (two-way ANOSIM; R = 1, p < 0.05) differences in species composition; the differences between unburnt sites were clearly expressed but less significant (R = 0.86, p < 0.05). Fungal species composition of burnt P. mugo and P. sylvestris sites was qualitatively different from that of corresponding unburnt sites (two-way ANOSIM; R ≥ 0.75, p < 0.05). The chronosequence of mycobiota in surface fire burns was less clearly defined than in crown fire sites, reflecting the greater patchiness of impacts of the surface fire. Although both fire types were detrimental or at least damaging to all functional groups of fungi (saprobic on soil and forest litter, wood-inhabiting, biotrophic, and mycorrhizal and lichenized fungi), their recovery and appearance (fructification) patterns varied between the groups and among the burn types. The end of the early post-fire fungal succession (cessation of sporocarp production of pyrophilous fungi) was recorded 3 years after the fire for both crown and surface fire types, which is earlier than reported by other authors. Rare or threatened fungal species that are dependent on fire regime were not recorded during the study. 相似文献
65.
Petar Kljajić Goran Andrić Marijana Pražić-Golić Dušanka Inđić Slavica Vuković 《Journal of pest science》2014,87(2):301-308
As very little is known about the impact of cold pre-treatments on insecticidal toxicity to the surviving stored-product insects, we examined the effects of cooling (?5 °C) on the toxicity of five contact insecticides to Sitophilus granarius adults from three populations (laboratory, field and selected). We determined: (a) weevil lethal time after exposure to ?5 °C, (b) the effects of two cold pre-treatments (LT20 and LT50—lethal time for 20 and 50 % of exposed adults) on 24 and 72 h recovery rates of laboratory adults after exposure to five insecticides and (c) deltamethrin, dichlorvos and malathion toxicity to two weevil populations with altered insecticide susceptibility after exposure to the LT20 and LT50 pre-treatments. The tested S. granarius populations showed no significant differences in their susceptibility to cooling. All insecticides except dichlorvos were more toxic to the laboratory weevils after 24 h than after 72 h recovery from the LT20 pre-treatment. Dichlorvos and deltamethrin were more toxic to the other two populations after 72 h of recovery. Comparing the effects of cold pre-treatment and non-treatment on the laboratory strain, no significant increase in the toxicity of insecticides was detected, while only deltamethrin was significantly more toxic to the field and selected populations recovering for 24 h (12.1 and 11.0 times, respectively) and 72 h (6.9 and 36.6 times) from the LT20 pre-treatment. In conclusion, only the shorter of the two cold pre-treatments was found effective in terms of increasing the insecticidal toxicity, especially against the populations with altered susceptibility to insecticides. 相似文献
66.
Maša Bošnjak Mojca Kržan Urša Lampreht Tratar Jožica Dolenc Maja Čemažar Alenka Seliškar 《Veterinary anaesthesia and analgesia》2021,48(1):35-41
ObjectiveTo investigate the pharmacokinetics of carprofen after a single intravenous (IV) dose and multiple oral doses administered to pigs undergoing electroporation of the pancreas.Study designProspective experimental study.AnimalsA group of eight female pigs weighing 31.74 ± 2.24 kg (mean ± standard deviation).MethodsCarprofen 4 mg kg?1 was administered IV after placement of a central venous catheter during general anaesthesia with isoflurane. Blood samples were collected 30 seconds before and 5, 10, 20, 30 and 60 minutes and 2, 4, 6, 8, 12 and 24 hours after carprofen administration. Subsequently, the same dose of carprofen was administered orally, daily, for 6 consecutive days and blood collected at 36, 48, 60, 72, 96, 120, 144 and 168 hours after initial carprofen administration. Plasma was analysed using liquid chromatography with mass spectrometry. Standard pharmacokinetic parameters were calculated by compartmental analysis of plasma concentration–time curves. Data are presented as mean ± standard error.ResultsThe initial plasma concentration of IV carprofen was estimated at 54.57 ± 3.92 μg mL?1 and decreased to 8.26 ± 1.07 μg mL?1 24 hours later. The plasma elimination curve showed a bi-exponential decline: a rapid distribution phase with a distribution half-life of 0.21 ± 0.03 hours and a slower elimination phase with an elimination half-life of 17.31 ± 3.78 hours. The calculated pharmacokinetic parameters were as follows: the area under the plasma concentration–time curve was 357.3 ± 16.73 μg mL?1 hour, volume of distribution was 0.28 ± 0.07 L kg?1 and plasma clearance rate was 0.19 ± 0.009 mL minute?1 kg?1. The plasma concentration of carprofen, administered orally from days 2 to 7, varied from 9.03 ± 1.87 to 11.49 ± 2.15 μg mL?1.Conclusions and clinical relevanceCarprofen can be regarded as a long-acting non-steroidal anti-inflammatory drug in pigs. 相似文献
67.
The spread of the genus Lactuca worldwide includes 16 species in Europe, 51 in Asia, 43 in Africa and 12 in America (mostly North American subcontinent). Natural distributions of Lactuca spp. are compared with the representation of wild Lactuca spp. in world genebank collections as recently summarized in the International Lactuca database (ILDB). A total of 27 wild Lactuca species are reported in world genebank collections in the ILDB, however, due to incorrect taxonomic determination the real number of species is lower. The substantial part (92%) of the collections is represented only by three species (L. serriola, L. saligna, L. virosa) and from a geographic viewpoint they are mostly European in origin. The autochthonous species originating from other continents (Asia, Africa, America), which form c. 83% of known Lactuca spp. richness, are very poorly represented in collections (only c. 3%). The majority of accessions originate from Europe (59%) and Asia (37%), nevertheless the whole area of natural distribution is not well covered. An extremely low number of accessions is available from Africa and America (2% each). Thus, the global biodiversity of Lactuca spp. germplasm is represented very poorly and is biased in genebank collections. For future studies of taxonomy, phytogeography, ecology, phylogenetic relationships, genetic diversity, inter- and intra-population structure, resistance research and practical breeding exploitation of wild Lactuca spp. germplasm, plant material from a wider ecogeographic distribution must be collected and introduced into genebank collections more intensively. 相似文献
68.
Zoldoš Vlatka Vidaković-Cifrek Željka Tomić Mihovil Papeš Dražena 《Water, air, and soil pollution》1997,94(1-2):181-190
Allium test has already been used to determine cytotoxicity of waste drilling fluids. In the present work the cytotoxicity of four pure chemicals (Defoamex, Idthin 400, Magco Thin and Slick Pipe) was investigated. Those chemicals are components of drilling fluids, therefore, they are usually constituents of oil and gas industry waste waters. The tested chemicals were prepared in 1:9 dilution and cytotoxic effects on root-tip meristem ofAllium ascalonicum were analysed after 24-, 48- and 72-hour-treatments. All samples showed cytotoxicity which was proved by cytogenetic parameters such as inhibition of mitotic activity and increase of mitotic abnormalities and chromosomal aberrations in comparison with the control. Almost all mitotic abnormalities induced by four chemicals tested were the result of disturbed spindle mechanisms accompanied with stickiness. Slick Pipe revealed the most prominent mitodepressive effect and induced a high number of abnormalities. It caused a significant decrease of mitotic activity and increase of mitotic abnormalities after all three treatment durations, while chemicals Defoamex and Magco Thin showed a significant decrease of mitotic activity only after 72-hour-treatment. Chemicals Defoamex, Idthin 400 and Magco Thin revealed a significant increase of mitotic abnormalities after 48- and 72-hour-treatments. 相似文献
69.
Márk Szalai Judit Papp Komáromi Renata Bažok Jasminka Igrc Barčić József Kiss Stefan Toepfer 《Journal of pest science》2011,84(1):133-142
Modelling population dynamics of the maize pest Diabrotica virgifera virgifera LeConte (western corn rootworm; Coleoptera: Chrysomelidae) requires knowledge on the growth rate (=net reproductive rate)
of the species. We investigated the generational (=annual) growth rate of D. v. virgifera in isolated maize fields in southern Hungary and eastern Croatia over several years. The population densities of D. v. virgifera were assessed by absolute counts of emerging adults in 90 gauze cages per study field. Emergence ranged from 1.3 to 30.7
adults per m2 in continuous maize field sections, and from 0.3 to 5.1 adults per m2 in adjacent first-year maize sections. The annual growth rates of D. v. virgifera ranged from 0.5 to 13, and averaged in close to 4. These experimentally assessed growth rates could complement growth estimates
in population dynamic models, particularly those for forecasting the population growth to economic thresholds or for estimating
population build-ups after new introductions of this alien species in Europe. As an example, the determined growth rate was
used to estimate that the first documented successful introduction of this species into Europe occurred between 1979 and 1984,
which is 8–13 years before the detection of this species and its larval damage in maize fields near Belgrade, Serbia, in 1992. 相似文献
70.
Irena Petrželová Aleš Lebeda 《European journal of plant pathology / European Foundation for Plant Pathology》2011,129(2):233-253
A metapopulation approach was applied to population studies of a common weed, Lactuca serriola (prickly lettuce). Seedlings grown from seed samples collected from 752 individual L. serriola plants in 50 populations occurring along an east-to-west transect across four European countries (Czech Republic, Germany,
Netherlands and United Kingdom) were screened for resistance to 10 common races of Bremia lactucae. Based on the recorded reaction patterns, host individuals were characterized into specific resistance (R-) phenotypes. Diversity
of R-phenotypes, their variation and distribution among and within European populations, was evaluated at different spatial
scales, i.e. from a metapopulation involving the entire European study area to individual plants occurring in local populations.
Generally, European populations of L. serriola have been shown to be highly susceptible to B. lactucae. However, large variation in L. serriola resistance was found both among and within individual countries. There was a clear gradient of increasing uniformity of race-specificity
moving from central to western Europe, as well as a slight decrease in the diversity of R-phenotypes. Populations in the United
Kingdom were the most divergent in terms of resistance structure from other geographic regions, and also were the most homogeneous,
most likely a consequence of the relatively greater degree of spatial isolation from other regions. Metapopulation, inter-
and intra-population variation in host resistance is discussed from the viewpoint of occurrence of race-specific interactions
in this wild plant pathosystem. 相似文献