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Lax Paola Rondan Dueñas Juan C. Andrade Alberto J. Doucet Marcelo E. 《European journal of plant pathology / European Foundation for Plant Pathology》2021,160(2):397-409
European Journal of Plant Pathology - Trichoderma aggressivum, a mycopathogen causing green mould disease, is a major problem in Agaricus bisporus cultivation due to crop loss, and resistance to... 相似文献
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Diego F. Vasquez Anngie Hernandez Diana Torres Felipe Borrero-Echeverry Paola Zuluaga Diego F. Rincon 《Plant pathology》2022,71(6):1282-1292
Plant–virus interactions are affected by environmental conditions that determine plant vulnerability to pathogens and the population dynamics of insect vectors. We hypothesize that drought enhances horizontal transmission by dampening the basal immunity of plants, which triggers symptom expression and vector manipulation. The potato yellow vein virus (PYVV) causes potato yellow vein disease (PYVD), a re-emerging epidemic of potato crops in South America, and is transmitted horizontally by the greenhouse whitefly (GWF), Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), or vertically through infected seed tubers. We investigated the role of drought and temperature as modulators of PYVD symptom expression, plant immune response, and vector survival, development and host preference. We found that drought induced symptom expression, suppressed the salicylic acid pathway and increased PYVV replication. GWF survival was reduced on PYVV-infected hosts and development was slowest when they fed on plants with PYVD symptoms, which also triggered adults’ attraction to PYVV-infected plants. However, adults previously fed on infected plants showed the opposite effect, being more attracted to PYVV-free plants. We propose a theoretical model that explains the role of drought in modulating potato–PYVV–GWF interactions and provides new insights into plant–virus–vector coevolution. 相似文献
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In our previous study, RAPD (Random Amplified Polymorphic DNA) analysis revealed species-specific markers for three medicinal Echinacea species (Asteraceae): E. angustifolia DC., E. pallida (Nutt.) Nutt. and E. purpurea (L.) Moench. In the present work, we have converted a RAPD marker (750 bp) for E. purpurea into a SCAR (Sequence Characterized Amplified Region) marker. SCAR-PCR, in fact, revealed the expected amplicon (330 bp) only in E. purpurea and not in the other two species, giving further evidence for differences in medicinal Echinacea spp. genome and confirming a greater similarity between E. pallida and angustifolia. 相似文献
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Initial cooling time before freezing affects post‐thaw quality and reproductive performance of rabbit semen 下载免费PDF全文
Michele Di Iorio Maria Antonietta Colonna Marsia Miranda Paola Principe Michele Schiavitto Silvia Cerolini Angelo Manchisi Nicolaia Iaffaldano 《Animal Science Journal》2018,89(9):1240-1244
The aim of this study was to investigate the effect of initial cooling time at 5°C during semen cryopreservation on post‐thaw quality and reproductive performance of rabbit semen. Pooled semen samples (n = 6) were divided into two subsamples and cooled at 5°C for 45 or 90 min. After cooling, the semen samples were diluted to a ratio of 1:1 (v:v) with a freezing extender composed of Tris‐citrate‐glucose (TCG) containing 16% of dimethylsulfoxide and 0.1 mol/L sucrose. The semen was subsequently loaded in 0.25 ml straws, equilibrated at 5°C and frozen in liquid nitrogen vapor. After thawing, sperm motility, viability, osmotic resistance, acrosome and DNA integrity were assessed. Our results indicate that the longer cooling time, that is, 90 min before cryopreservation significantly improves sperm post‐thaw viability, motility and fertility. In fact, reproductive performances obtained with semen frozen after a 90 min cooling time were similar to those produced by fresh semen insemination. Hence, the present research provides an effective freezing protocol for rabbit semen that will allow for the creation of a sperm cryobank for the conservation of Italian rabbit genetic resources, as well as the use of frozen semen doses in commercial farms. 相似文献
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Cairoli P Pieraccini S Sironi M Morelli CF Speranza G Manitto P 《Journal of agricultural and food chemistry》2008,56(3):1043-1050
A number of N2-alkyl and N2-acyl derivatives of guanosine 5'-phosphate (GMP) have been synthesized and tested for their synergistic effect with monosodium L-glutamate (MSG), the prototypical substance imparting umami taste to savory-based foods. Capacities to enhance the taste intensity of MSG (gamma values) were estimated through subjective comparisons of MSG/nucleotide mixtures in water with appropriate solutions of MSG alone. Assuming beta = gamma[nucleotide]/gamma[IMP], beta values of the N2-substituted GMPs were found in the range 1.2-5.7. Such values appear to be related to the chain length of the substituent in the 2-position of the purine nucleus and dependent on the replacement of a CH 2 group with an S atom and/or with an alpha-CO group. These findings indicate that the exocyclic NHR group of the guanine moiety is actively implicated in the synergism between GMP derivatives and MSG. Theoretical calculations suggest that an anti conformation is probably assumed by ribonucleotide molecules interacting with umami receptors. 相似文献
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Ricardo Marcos Marta Santos Fernanda Malhão Rui Pereira Ana Cristina Fernandes Luís Montenegro Paola Roccabianca 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):201-205
Abstract: A 4‐year‐old, domestic shorthair, female spayed cat was presented for decreased appetite and depression. Severe pancytopenia with erythrocyte autoagglutination was found. The cat was seronegative for feline immunodeficiency and leukemia viruses. Immune‐mediated hemolytic anemia was suspected but no response to treatment with a blood transfusion, enrofloxacin, and prednisone was observed. Blood and bone marrow smears obtained 11 days later contained Leishmania amastigotes in the cytoplasm of neutrophils and macrophages, respectively. Serologic and PCR testing of peripheral blood confirmed infection with Leishmania infantum. Despite treatment, the cat worsened clinically and was euthanized. At necropsy, visceral dissemination of the parasite was confirmed. The findings in this case indicate that visceral leishmaniasis should be considered as a differential diagnoses in cats with pancytopenia in areas endemic for Leishmania. In addition, amastigotes may be observed in peripheral blood neutrophils. 相似文献