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991.
Paulo Gouveia Susana Dandlen ?ngela Costa Natália Marques Gustavo Nolasco 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):237-245
GLRaV-3, a member of the Closteroviridae family and type member of the genus Ampelovirus, is involved in the grapevine leafroll disease. Until now no RNA silencing suppressor has been found among viruses of this
genus, contrary to what happens with a large number of other viral genera. In the sister genus Closterovirus, RNA silencing suppressors are present in the 3’ end of the genome and have molecular weights close to 20 KDa. To test for
RNA suppressing activity screening of p21, p19.6 and p19.7 proteins, coded for in an analogous genomic location of the GLRaV-3
was undertaken. Only p19.7 revealed suppressor activity demonstrated in diverse silencing inducing systems. This suppressor
is able to overcome strong silencing inducers and shares several properties with the BYV p21-like family of suppressors of
the closteroviruses. This is the first report of an RNA silencing suppressor in the genus Ampelovirus. 相似文献
992.
André Costa da Silva Paulo Estev?o de Souza José Eduardo Brasil Pereira Pinto Bruno Marques da Silva Douglas Carvalho Amaral Eudes de Arruda Carvalho 《European journal of plant pathology / European Foundation for Plant Pathology》2012,134(4):865-871
The objective of the work was to evaluate the effect of essential oils as a preventive treatment to control Asian soybean rust. Initially the fungitoxic effect of the essential oils of Hyptis marrubioides, Aloysia gratissima and Cordia verbenacea was tested on the urediniospores of Phakopsora pachyrhizi, through in vitro tests. The in vivo test was set up in a greenhouse, using cultivar MGBR-46. The treatments consisted of the three oils at different concentrations, a fungicide based on pyraclostrobin + epoxyconazole and a control. To verify the potential of the essential oils in preventive treatment, inoculation was conducted at 0, 6, 12 and 24?h intervals, after application of the treatments. All treatments inhibited 100% of Phakopsora pachyrhizi germination. In the in vivo test, it was observed that all of the oils were efficient in controlling soybean rust, by preventive treatment, mainly at the higher concentrations. Efficiency of the oils was reduced with the increase of the interval between the application of the treatments and the onset of the pathogen. The essential oils, at the tested dosages, were not as efficient as the pyraclostrobin + epoxyconazole based fungicide. 相似文献
993.
João Paulo Rodrigues Marques Marcel Bellato Spósito Alexandre Furtado Silveira Mello Lilian Amorim Matheus Mondin Beatriz Appezzato-da-Glória 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(2):439-448
In Brazil, citrus black spot (CBS) caused by Guignardia citricarpa is a major disease that has different symptoms on fruit. In this study, fruit of Citrus sinensis infected by G. citricarpa and showing the symptoms false melanosis, freckle spot and hard spot were cross-sectioned and analysed anatomically and histochemically
by light microscopy. Immuno-histological assays were performed. All symptoms were accompanied by a thickening of the cuticle.
False melanosis lesions did not contain pycnidia and remained restricted to the epicarp or to the first layers of the mesocarp.
The stomata in this type of lesion showed phenolic compounds in the guard cells and in the sub-stomatal chamber. In some samples,
the guard cells and their surrounding cells lysed, and a wound meristem began to form underneath them. Freckle spot and hard
spot lesions had very similar histological alterations to the epicarp and mesocarp, but in our samples only hard spot lesions
contained pycnidia. Both of these symptoms were accompanied by protein inclusions. Epidermal and sub-epidermal cells located
in the oil-gland region were obliterated, causing alterations in these structures. All symptoms had regions that stained strongly
for lipids and phenols. 相似文献
994.
Natália T. Marques Ângela A. Costa Débora Lopes Gonçalo Silva Gustavo Nolasco 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):229-235
The p20 protein encoded by the Citrus Tristeza Virus (CTV) was previously identified as a RNA silencing suppressor. In this study, we analyzed the p20’s suppressing activity
from five phylogenetic groups of CTV, using the co-infiltration assay of Green fluorescence protein (GFP) gene and the suppressor
gene in 16C line Nicotiana benthamiana plants. Green fluorescence, GFP mRNA relative levels and GFP specific siRNAS were compared showing in most cases, only slight
differences. Contrary to previous studies, the p20 suppressor was not able to impede neither short range nor systemic spreading
of RNA silencing. The suppressor from the phylogenetic group 4 revealed a much reduced activity when compared with the others.
At present we still don’t know whether this property is a characteristic of this group or an atypical feature due to a unique
point mutation. The differences in the symptom type and intensity originated by isolates belonging to the phylogenetic groups
assayed could not be related to differences to the p20 suppressor’s activity. 相似文献
995.
AV Pereira SA Pereira IDF Gremião MP Campos AMR Ferreira 《Australian veterinary journal》2012,90(11):448-450
This study compared the sensitivity of acetate tape impression and skin squeezing with that of deep skin scraping for the diagnosis of demodicosis in dogs. Demodex canis was detected in 100% of acetate tape impressions obtained after skin squeezing and in 90% of deep skin scrapings. There was a significant difference (P < 0.001) between the techniques in the total number of mites detected. Acetate tape impression with skin squeezing was found to be more sensitive than deep skin scraping and is an alternative diagnostic method for canine demodicosis. 相似文献
996.
Moraes ML Ribeiro AM Kessler AM Ledur VS Fischer MM Bockor L Cibulski SP Gava D 《Journal of animal science》2012,90(8):2590-2598
An experiment was conducted to evaluate the effect of CLA on the immune response and performance of piglets when subjected to an immune challenge. A total of 32 weanling pigs (17 to 23 d of age) with an initial BW of 8.9 kg were allotted to a 3 × 2 factorial arrangement of treatments. There were 3 levels of dietary CLA (0%, 1%, and 2%) and 2 levels of lipopolysaccharide (LPS) challenge (unchallenged and challenged). Challenged pigs were challenged on d 7 and 21. On d 4 and 18, all pigs were inoculated with BSA for assessment of IgG production. There was no difference in growth performance among piglets receiving different CLA supplementation levels. However, LPS-challenged piglets had poorer BW (P < 0.05), ADFI (P < 0.01), and ADG (P < 0.001) compared with the control group at d 35 postweaning. Lipopolysaccharide-challenged piglets also had increased respiratory rate (P < 0.001) and rectal temperature (P < 0.001), and decreased plasma proteins, hematocrit, and white blood cell counts (P < 0.05). Production of IgG against BSA was increased in the 1% CLA supplementation group (P < 0.001), indicating that CLA has an immunomodulatory effect. Supplementation with CLA did not affect lymphocyte proliferation, percentage of CD4(+) and CD8(+) cells, plasma proteins, red and white blood cell count, respiratory rate, or rectal temperature after LPS challenge. Although CLA supplementation did not influence growth performance or certain immune system measurements, the increased IgG titers with 1% CLA dietary supplementation indicate that it has a beneficial effect on the humoral immune system of weaned piglets. 相似文献
997.
The four categories of protected areas described in Spain's 1975 Protection of Natural Spaces Act are defined and the programme of action derived from the Law is outlined, specifying the characteristics which may lead to inclusion under the protection plans. Finally, the real situation two years after the Act is analysed and some conclusions are drawn. The situation for conservation is rather discouraging but the need for planning to give greater consideration to conservation values is becoming more and more generally accepted. 相似文献
998.
F. Martí n de Santa Olalla Ma as A. Brasa Ramos C. Fabeiro Cort s D. Fern ndez Gonz lez H. L pez C rcoles 《Agricultural Water Management》1999,40(2-3):195-205
The great expansion of irrigated lands using groundwater has often caused the exploitation of aquifer reserves beyond their recharge capacity. The development of management tools which can harmonize resource exploitation with reserve sustainability is the objective of an interesting experience being accomplished in the aquifer 08.29 in Mancha Oriental, Spain. This paper offers a summary of this ongoing project (GESMO), pointing out the specific role of the Irrigation Advisory Service. The general objective of the project is to create an integrated and integral management system of the aquifer as well as to prepare appropriate techniques for its adequate exploitation. Integral management means that both supply and demand management are considered, including the socio-economic and environmental perspectives. The concept of integrated management implies that the process must involve the majority of economic and social agents affected.
Management is founded on a Decision Support System (DSS) which takes into consideration different possible options. The DSS must contemplate the impacts on the environment, mainly the aquifer reserve losses and the increase of nitrates concentration in groundwater. The project directly affects more than 5000 agricultural users, irrigating about 100 000 ha with the aquifer water resources, as well as the whole population living in this region. Results of this project, including irrigation technologies developed may be useful for other areas in the Mediterranean Basin where similar cases occur. 相似文献
999.
Maximum daily trunk shrinkage and stem water potential reference equations for irrigation scheduling of lemon trees 总被引:3,自引:2,他引:1
Maria Fernanda Ortuño Juan José Brito Yelitza García-Orellana Wenceslao Conejero Arturo Torrecillas 《Irrigation Science》2009,27(2):121-127
Measurements of midday stem water potential (ψstem) and maximum daily trunk shrinkage (MDS) were done over a 3-year period in adult Fino lemon trees (Citrus
limon (L.) Burm. fil.) grafted on sour orange (C. aurantium L.) rootstocks. Plants were irrigated daily above their water requirements in order to obtain non-limiting soil water conditions.
The results indicated that reference equations can be obtained for MDS and ψstem by pooling data across several seasons using crop reference evapotranspiration (ETo), daily mean vapor pressure deficit (VPDm) and mean daily air temperature (T
m) in the case of MDS, and ETo in the case of ψstem. The best predictor of MDS under non-limiting soil water conditions was T
m, suggesting that MDS reference values can be obtained by means of easy and cheap measurements. MDS and ψstem values were not influenced significantly by yield or crop load variations between years. A negative linear relationship between
MDS and ψstem was found, pointing to an unchanging radial hydraulic conductivity in the bark tissues and suggesting that the MDS is controlled
by water potential. 相似文献
1000.
Ferreira AJ Peleteiro MC Correia JH Jesus SO Goulão A 《The Journal of small animal practice》2005,46(6):286-290
A small-cell carcinoma of the lung was identified in a six-year-old female German shepherd dog with a history of chronic lameness of the left forelimb, Horner's syndrome and sensory deficits on the caudal portion of the left forelimb below the elbow. A mass, the exact location of which was difficult to ascertain, was identified during radiographic examination of the thorax. It was easily identified, using magnetic resonance imaging, as an apical tumour of the left lung with dorsal extension and involvement of paraspinal structures, such as spinal nerve roots C8 to T1 and the sympathetic trunk. Postmortem examination confirmed a mass in the left apical lobe of the lung, compatible with a diagnosis of small-cell carcinoma by histopathology and immunohistochemistry. This clinical presentation is similar to Pancoast syndrome described in humans. 相似文献