Current situation of Tomato yellow leaf curl virus in Portugal     

D. Louro  J. E. Fernandes  A. Quinot 《EPPO Bulletin》2002,32(1):47-47

The name Tomato yellow leaf curl virus (TYLCV) has been applied to a group of virus species of the genus Begomovirus in the family Geminiviridae that cause a similar tomato disease worldwide. In 1995, TYLCV was first reported in Algarve (southern Portugal) as responsible for an epidemic outbreak of a severe tomato disease. Molecular data have shown that this Portuguese TYLCV isolate was distinct from those previously reported in Europe, as it belonged to the TYLCV-Israel species ¹ . Since then, TYLCV epidemics have occurred annually, being a limiting factor mainly for autumn/winter glasshouse tomato crops. In 1998, TYLCV was also found associated with the emergence of a novel disease of Phaseolus vulgaris in Algarve. The affected bean plants were severely stunted and gave no marketable yield. However, the disease occurs only sporadically, even in conditions of high TYLCV infection pressure. Recently, Tomato chlorosis virus (ToCV), a whitefly-transmitted bipartite closterovirus (genus Crinivirus , family Closteroviridae ), was found associated with an unusual tomato yellow leaf syndrome, in single or mixed infection with TYLCV. The impact of this new pathosystem on tomato production has yet to be determined. Surveys are in progress in mixed cropping systems infested with whiteflies. So far, TYLCV and ToCV diseases are limited to the Algarve region.  相似文献   

Morphofunctional description of mucous cells in the gills of the Arapaimidae Arapaima gigas (Cuvier) during its development          下载免费PDF全文

C. A. Ramos  O. T. F. da Costa  W. L. P. Duncan  M. N. Fernandes 《Anatomia, histologia, embryologia》2018,47(4):330-337

The gill structure of the Amazonian fish Arapaima gigas (Cuvier 1829) shows ontogenetic changes during development, particularly due the transition from the aquatic to the obligatory air breathing mode of respiration. However, three main cell types can be found in the gills: mitochondrial rich cells, pavement cells and mucous cells (MCs). The MCs are involved in the secretory pathway. The functions of the secreted molecules include mechanical protection of epithelia, protection against parasites and bacterial infection, and role on ion regulation. In this study, we analysed mucous cell location and mucous cell type, based on pH, during the development of A. gigas. Using samples obtained from the environment, gills were collected and fixed in buffered solution. Histological techniques for the identification of MCs were performed Alcian Blue (AB) and periodic acid‐Schiff (PAS). The results showed the presence of PAS+ and AB+ cells in the whole filament in all examined fish. In animals less than 50 g, few MCs were present, and no differences were observed in AB+ and PAS+ cells. In animals weighing close to 500 g, more PAS+ cells than AB+ cells were observed, and in animals that weighed more than 1,000 g, more AB+ cells than PAS+ cells were observed. These observations may be a result of the ontogenetic changes in the gill epithelia, which can change the osmorespiratory compromise in ion regulation functions as well the glycosaminoglycans secreted by PAS cells, which in large animals can play a role in the protection against parasites and bacterial infection.  相似文献   

Bovine viral diarrhea virus subgenotype 1b in water buffalos (Bubalus bubalis) from Brazil     

Paixão  Sonália Ferreira  Fritzen  Juliana Torres Tomazi  Crespo  Sarah Elizabeth Izzo  de Moraes Pereira  Helder  Alfieri  Alice Fernandes  Alfieri  Amauri Alcindo 《Tropical animal health and production》2018,50(8):1947-1950

Tropical Animal Health and Production - Serological studies have characterized the presence of the bovine viral diarrhea virus (BVDV) infection in water buffalo herds worldwide. However, the...  相似文献   

ACE inhibition in goats under fixed‐time artificial insemination protocol increases the pregnancy rate and twin births          下载免费PDF全文

VP Fernandes Neto  MNN Silva  AS Costa  D Kunkel  AS Júnior  LCS Feitosa  MCS Muratori  APR Costa 《Reproduction in domestic animals》2018,53(4):1006-1008

To assess the effect of the angiotensin‐converting enzyme (ACE) inhibition on the efficiency of the fixed‐time artificial insemination (TAI), 69 goats were divided randomly into two groups: enalapril (n = 35) and control (n = 34). In the experiment, all animals underwent the protocol of fixed‐time artificial insemination for 12 days. Enalapril group received enalapril maleate dissolved in saline (Enalapril, Lab Teuto Ltda) subcutaneously at the following doses: 0.2 mg/kg/day in D0‐D2; 0.3 mg/kg/day in D3‐D6 and 0.4 mg/kg/day in D7‐D11. The control group received the corresponding volume of 0.9% saline solution. We performed a single insemination 36 hr after sponge removal using frozen semen from two adult male goats with recognized fertility. The ultrasound pregnancy diagnosis was 30 days after the artificial insemination (AI). There was significant increase in pregnancy rates and twinning as well as a decrease in foetal loss in animals receiving enalapril (p < .01). The use of ACE inhibitors during the TAI protocol was shown to be a promising alternative to increase the efficiency of such reproductive biotechnology.  相似文献   

Effects of CO2 Enrichment and Drought on Photosynthesis,Growth and Yield of an Old and a Modern Barley Cultivar          下载免费PDF全文

I. Schmid  J. Franzaring  M. Müller  N. Brohon  O. C. Calvo  P. Högy  A. Fangmeier 《Journal of Agronomy and Crop Science》2016,202(2):81-95

Susceptibility of crops to drought may change under atmospheric CO₂ enrichment. We tested the effects of CO₂ enrichment and drought on the older malting barley cultivar Golden Promise (GP) and the recent variety Bambina (BA). Hypothesizing that CO₂ enrichment mitigates the adverse effects of drought and that GP shows a stronger response to CO₂ enrichment than BA, plants of both cultivars were grown in climate chambers. Optimal and reduced watering levels and two CO₂ concentrations (380 and 550 ppm) were used to investigate photosynthetic parameters, growth and yield. In contrast to expectations, CO₂ increased total plant biomass by 34 % in the modern cultivar while the growth stimulation was not significant in GP. As a reaction to drought, BA showed reduced biomass under elevated CO₂, which was not seen in GP. Grain yield and harvest index (HI) were negatively influenced by drought and increased by CO₂ enrichment. BA formed higher grain yield and had higher water‐use efficiency of grain yield and HI compared to GP. CO₂ fertilization compensated for the negative effect of drought on grain yield and HI, especially in GP. Stomatal conductance proved to be the gas exchange parameter most sensitive to drought. Photosynthetic rate of BA showed more pronounced reaction to drought compared to GP. Overall, BA turned out to respond more intense to changes in water supply and CO₂ enrichment than the older GP.  相似文献   

Multi‐centre retrospective study of long‐term outcomes following traumatic elbow luxation in 37 dogs          下载免费PDF全文

D. Sajik  R. L. Meeson  N. Kulendra  C. Jordan  D. James  I. Calvo  M. Farrell  E. Kulendra 《The Journal of small animal practice》2016,57(8):422-428

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Effect of supplementation of beef cattle with different protein levels and degradation rates during transition from the dry to rainy season     

Rodolfo Maciel Fernandes  Chafic Mustafé de Almeida  Bruna Caldas Carvalho  João Alexandrino Alves Neto  Verônica Aparecida Costa Mota  Flávio Dutra de Resende  Gustavo Rezende Siqueira 《Tropical animal health and production》2016,48(1):95-101

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Herd-level prevalence and risk factors for bovine viral diarrhea virus infection in cattle in the State of Paraíba,Northeastern Brazil     

Leise Gomes Fernandes  Adriana Hellmeister de Campos Nogueira  Eliana De Stefano  Edviges Maristela Pituco  Cláudia Pestana Ribeiro  Clebert José Alves  Tainara Sombra Oliveira  Inácio José Clementino  Sérgio Santos de Azevedo 《Tropical animal health and production》2016,48(1):157-165

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Reflected‐light Influences the Coloration of the Peppermint Shrimp,Lysmata boggessi (Decapoda: Caridea)          下载免费PDF全文

Natalia S. Calvo  Magaly RoldÁn‐Luna  Jorge A. Argáez‐Sosa  Gemma L. Martínez‐Moreno  Maite Mascaró  Nuno Simões 《Journal of the World Aquaculture Society》2016,47(5):701-711

One alternative to contribute to the reduction of the pressure on coral reef ecosystems brought about by an increasing demand for marine aquarium ornamentals is to improve and further develop the culture of desirable species for trade. Peppermint shrimp from the genus Lysmata are among the most intensively traded decapod in the trade and while several studies have been conducted to improve its culture, individuals obtained from culture facilities are generally paler than those collected from the wild. Because color is a fundamental component of the price tag on most marine ornamental live species, poorly colored animals command a lower price, reducing competitiveness. In this study, we evaluate the influence of tank background color (reflected light) on the morphological coloration change of Lysmata boggessi. In a 15‐d experiment, 30 individuals were exposed either to reflected‐red or white light and the relative change of coloration between initial and final moments was quantified with photography (RGB color model). At the end of the experimental period, shrimp exposed to red‐reflected light presented a more intense red coloration than those exposed to white‐reflected light. These results demonstrate that a simple change in background tank color can enhance shrimp external coloration. Such a cheap‐to‐implement procedure can support the culture of more colorful, hence more valuable ornamental shrimp that can compete with those captured from the wild.  相似文献   

Genetic Diversity in Colletotrichum gloeosporioides from Stylosanthes spp. at Centers of Origin and Utilization     

Weeds PL  Chakraborty S  Fernandes CD  d'A Charchar MJ  Ramesh CR  Kexian Y  Kelemu S 《Phytopathology》2003,93(2):176-185

ABSTRACT Using molecular markers, this work compares the genetic diversity in Colletotrichum gloeosporioides infecting species of the tropical forage legume Stylosanthes at the center of origin in Brazil and Colombia with that of Australia, China, and India, where Stylosanthes spp. have been introduced for commercial use. There was extensive diversity in the pathogen population from Brazil, Colombia, China, and India. The Australian pathogen population was least diverse probably due to its geographical isolation and effective quarantine. The extensive diversity in China and India means that threats from exotic pathogen races to Stylosanthes pastures can potentially come from countries outside the South American center of origin. In Brazil and India, both with native Stylosanthes populations, a high level of genetic differentiation in the pathogen population was associated with sites where native or naturalized host population was widely distributed. There was limited genetic diversity at germplasm evaluation sites, with a large proportion of isolates having identical haplotypes. This contrasts recent pathogenicity results for 78 of the Brazilian isolates that show hot spots of complex races are more common around research stations where host germplasm are tested, but few are found at sites containing wild host populations. For a pathogen in which the same races arise convergently from different genetic backgrounds, this study highlights the importance of using both virulence and selectively neutral markers to understand pathogen population structure.  相似文献