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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
104.
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
105.
Chemical composition and antimicrobial activity of Momordica charantia seed essential oil 总被引:1,自引:0,他引:1
The essential oil obtained from the seeds of Momordica charantia was analyzed by GC/MS. Twenty-five components, representing 90.9% of the oil, were identified. The main constituents were trans-nerolidol, apiole, cis-dihydrocarveol and germacrene D. Furthermore, the oil was tested for its antibacterial and antifungal activities. Staphylococcus aureus was found to be the most sensitive microorganism with MIC values <500 microg/ml. 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
108.
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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Gabriele Ghisleni Valeria Grieco Marcello Mazzotti Mario Caniatti Paola Roccabianca Eugenio Scanziani 《Journal of veterinary diagnostic investigation》2003,15(2):170-173
A Domestic Shorthaired cat was presented with coughing and severe respiratory distress. Thoracic radiographs revealed a lobar mass and numerous additional cavitated intrapulmonary masses. The cat was euthanized and submitted for necropsy. Histological examination of the large mass revealed 2 distinct neoplastic components consisting of bronchial adenocarcinoma admixed with neoplastic areas composed of highly atypical undifferentiated spindle cells (sarcomatous component). Simultaneous expression of vimentin and cytokeratin by a subpopulation of neoplastic epithelial cells and by rare neoplastic spindle cells was identified. On the basis of histology and immunohistochemical results, a diagnosis of primary pulmonary carcinosarcoma with intrapulmonary epithelial metastases was made. Pulmonary carcinosarcoma is a well-known pathological entity in humans. It is a rare tumor in animals and has not been previously reported in cat. 相似文献
110.
Luca Fava Paola Bottoni Angela Crobe Anna Barra Caracciolo Enzo Funari 《Pest management science》2001,57(12):1135-1141
The metabolites of pesticides can contaminate groundwater and pose a risk to human health when this water is used for drinking. This paper reports the results of a laboratory study on aldicarb and its main metabolites, aldicarb sulfone and aldicarb sulfoxide. Aldicarb and its metabolites showed Koc values (6–31) which were lower than that of atrazine (55), indicating that they are very mobile in soil. They are less persistent than atrazine (DT50 = 25 days), with DT50 values from less than 1 day and up to 12 days. Aldicarb behaved as a non‐leacher, whereas its metabolites clearly showed the characteristics of leachers. Aged residue leaching experiments showed that aldicarb can occur at high concentrations in the leachate, together with its two metabolites. The leachate composition depends on the incubation time of the parent compound. Aldicarb and its metabolites can form various mixtures in groundwater on the basis of the time elapsing between the application of the insecticide and the first significant rainfall. This study confirms the characteristics of contaminants of aldicarb and especially its metabolites, as reported in the literature. © 2001 Society of Chemical Industry 相似文献