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611.
612.
de Carvalho LB Alves PL González-Torralva F Cruz-Hipolito HE Rojano-Delgado AM De Prado R Gil-Humanes J Barro F de Castro MD 《Journal of agricultural and food chemistry》2012,60(2):615-622
Digitaria insularis biotypes resistant to glyphosate have been detected in Brazil. Studies were carried out in controlled conditions to determine the role of absorption, translocation, metabolism, and gene mutation as mechanisms of glyphosate resistance in D. insularis. The susceptible biotype absorbed at least 12% more (14)C-glyphosate up to 48 h after treatment (HAT) than resistant biotypes. High differential (14)C-glyphosate translocation was observed at 12 HAT, so that >70% of the absorbed herbicide remained in the treated leaf in resistant biotypes, whereas 42% remained in the susceptible biotype at 96 HAT. Glyphosate was degraded to aminomethylphosphonic acid (AMPA), glyoxylate, and sarcosine by >90% in resistant biotypes, whereas a small amount of herbicide (up to 11%) was degraded by the susceptible biotype up to 168 HAT. Two amino acid changes were found at positions 182 and 310 in EPSPS, consisting of a proline to threonine and a tyrosine to cysteine substitution, respectively, in resistant biotypes. Therefore, absorption, translocation, metabolism, and gene mutation play an important role in the D. insularis glyphosate resistance. 相似文献
613.
Sybuia Priscila Ayumi de Castro-Prado Gabriela de Carvalho Nunes William Mário Zanutto Carlos Alexandre Kaneshima Edilson Nobuyoshi Soares Dartanhã José da Silva Franco Claudinéia Conationi de Freitas Mathias Paulo Cezar de Castro-Prado Marialba Avezum Alves 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):937-950
European Journal of Plant Pathology - Charcoal rot is an economically important fungal disease of economically important crops. Several species of the Macrophomina genus, such as M.... 相似文献
614.
dos Santos DR Vitral CL de Paula VS Marchevsky RS Lopes JF Gaspar AM Saddi TM Júnior NC Guimarães Fde R Júnior JG Ximenes LL Souto FJ Pinto MA 《Veterinary journal (London, England : 1997)》2009,182(3):474-480
Active hepatitis E virus (HEV) infections in two Brazilian swine herds were investigated. In study 1, 26 piglets born to five anti-HEV positive sows were monitored from birth to post-partum week 22. Serum samples were screened for the detection of anti-HEV antibodies and a nested RT-PCR used to examine the HEV genome. Passive transfer of immunity was confirmed. At week 22, 23/26 (88.4%) of the piglets had seroconverted. Genome amplification was achieved in a feces pool from one holding pen and in one serum sample, both from 13-week-old animals. Histology was suggestive of a potential HEV infection. In the second study, 47 piglets born to six anti-HEV-positive sows were monitored after weaning. Seroconversion was determined in eight animals at 6-8 weeks of age. HEV RNA was detected in two pools from a holding pen for 12-16-week-old animals. Brazilian isolates were classified as genotype 3. This is the first molecular evidence of HEV infection in Brazilian pig herds. 相似文献
615.
Aline Costa de Lucio Antonio Sérgio Ferraudo Leticia Zoccolaro de Oliveira Adriana Santana do Carmo Benner Geraldo Alves Kele Amaral Alves Solange Almeida Luis Alfredo Deragon William Pereira Luisa Cunha Carneiro Vera Fernanda Martins Hossepian de Lima 《Tropical animal health and production》2014,46(5):765-770
The aim of this study was to evaluate the effects of breed and season on semen quality parameters of zebu bulls. Data (1,632 registers) of semen production from Gir (n?=?4) and Nelore (n?=?15) bulls were collected between October 2005 and November 2009. The ejaculates were collected twice a week during various seasons (summer, fall, winter, and spring) and evaluated for the following semen parameters: ejaculate volume, sperm concentration, sperm motility, forward progressive motility (FPM), and sperm morphology. Factor analysis was used to determine the relationship among variables. The effect of breed (Gir and Nelore) and season and their cross effect on each parameter and extracted factor were tested using ANOVA. A negative correlation (P?<?0.05) was observed between FPM and proximal droplet, as well as with abnormal loose head, abnormal small head, pouch formation, abnormal mid-peace, and strongly folded tail. Gir bull sperm showed more major defects, detached acrosome, and minor FPM (P?<?0.01), whereas Nelore bulls showed a higher number of sperm with normally loose head. 相似文献
616.
Dinalva Alves Mochi Antonio Carlos MonteiroAna Carolina Ribeiro Machado Luciana Yoshida 《Veterinary parasitology》2010
The present study assessed the pathogenic effect of isolates E9, IBCB425 and IBCB159 of the Metarhizium anisopliae fungus, JAB06, JAB07 and AM09 of Beauveria bassiana, IBCB133 and CB75 of Isaria fumosorosea (=Paecilomyces fumosoroseus) and CG189 and CG195 of Isaria farinosa (=Paecilomyces farinosus) against eggs and larvae of the horn fly Haematobia irritans. Eggs were inoculated with suspensions containing 106, 107 and 108 conidia ml−1 of the fungal isolates and observed after 48 h to determine viability. In the larvae study, eggs were allowed to hatch into fresh bovine feces that had been treated with 108, 107 or 106 conidia mg feces−1. In both studies, 5 days after initial procedures, all formed pupae were transferred to an incubator at 27 ± 0.5 °C until the emergence of the adult flies was complete. The M. anisopliae isolates did not cause the death of H. irritans eggs, but they did promote the death of larvae that hatched from treated eggs, and therefore increased the total mortality. Isolate E9 promoted 100% mortality of treated larvae at a concentration of 108 conidia ml−1. For the B. bassiana isolates, no activity was observed against insect eggs or larvae. Both I. fumosorosea isolates promoted significant mortality (p < 0.05) of eggs at every concentration of conidia. Isolate CG195 of I. farinosa increased the mortality of larvae and pupae that hatched from treated eggs and promoted significant total mortality (p < 0.05) of the insect at every concentration of conidia. 相似文献
617.
J. R. Martínez Aranzales B. S. Cândido de Andrade G. E. Silveira Alves 《Journal of veterinary pharmacology and therapeutics》2015,38(3):257-264
Phenylbutazone (PBZ) is widely used in equine medicine, and its side effects on the gastrointestinal tract are well known. The inhibition of prostaglandins and the oxidative stress induced by nonsteroidal anti‐inflammatory drugs (NSAIDs) are described as mechanisms of gastric mucosal injury in humans. In horses, only the secondary effect of changes in cyclooxygenases is related to gastric mucosal injury. The objective of this study was to evaluate the effect of PBZ on certain antioxidative/oxidative parameters of the gastric mucosa. The concentrations of antioxidants and oxidants (superoxide dismutase, SOD; catalase, CAT; nitric oxide, NO; total glutathione, GSH; myeloperoxidase, MPO; and malondialdehyde, MDA), PGE2 levels, and the ulcerative lesions score were assessed. The results demonstrated decreased levels of antioxidant variables, increased levels of oxidant variables, and alterations in the prostaglandin E2 (PGE2), myeloperoxidase (MPO), and glutathione (GSH) levels. In conclusion, PBZ induces oxidative stress in the gastric glandular mucosa of horses by changing the antioxidant–oxidant balance of this surface, which might be regarded as another mechanism of injury in the horse stomach. 相似文献
618.
Géssica Mylena Santana Rêgo Iêda Alana Leite de Souza Gabrielle Avelar Silva Mara Elisa Soares de Oliveira Maria Alves Ferreira 《Forest Pathology》2023,53(2):e12803
Fungi of the Cryphonectriaceae family are globally known to be tree pathogens. In Brazil, several species of Chrysoporthe have been found causing stem and branch cankers in Pleroma (= Tibouchina) spp. Recently, Chrysoporthe puriensis was described as a new species causing stem and branch cankers in Pleroma granulosum, Pleroma candolleanum, and Pleroma heteromallum, all native species of the Melastomataceae family. During an investigation to collect isolates of the Cryphonectriaceae family in an important Brazilian biome, the Atlantic Forest, in Serra do Mar, structures typical of Chrysoporthe species were found in a different host, Pleroma mutabile. Fruiting bodies present in the bark of these trees were collected and isolated. The isolates were submitted on morphological characterization and phylogenetic analyses of the internal transcribed spacer (ITS) and β-tubulin gene regions using Maximum likelihood, Bayesian inference and Maximum parsimony methods. The isolates collected, for this study, were identified as C. puriensis. Pathogenicity tests on seedlings of Pleroma species and Eucalyptus clones revealed C. puriensis can infect and cause canker in these plant species as mortality. The results demonstrate the importance of delimiting the C. puriensis collection range to track its dissemination in other hosts. No host specificity was observed in the inoculation tests, suggesting this is an important finding, the pathogen causes diseases and mortality in several plants of the Atlantic Forest. Additionally, the pathogen can affect others hosts, such as Eucalyptus clones in commercial plantations. 相似文献
619.
P.M. Chalk R. de F. Souza S. Urquiaga B.J.R. Alves R.M. Boddey 《Soil biology & biochemistry》2006,38(9):2944-2951
Legumes may respond to non-rhizobial inoculants such as arbuscular mycorrhizal (AM) fungi either through an effect on plant growth or, in addition, through an effect on the function of the legume-Rhizobium symbiosis. We have examined the literature where the application of 15N isotope dilution methodology permits the effect of indigenous AM and AM inoculants to be quantitatively separated into plant-growth-mediated and biological N2 fixation (BNF)-mediated components. These studies clearly demonstrate the beneficial effects that both indigenous and inoculated AM have on legume growth, N uptake and the proportional dependence of the legume on atmospheric N2. While the published data allow an assessment of various biological, edaphic and environmental factors that affect the response of various legumes to AM inoculation, they also highlight the paucity of quantitative field data and the lack of understanding of the interaction of legume genotype with AM species with respect to legume symbiotic performance. 相似文献