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31.
A two year study (2008-2009) was carried out to monitor the Usutu virus (USUV) circulation in Italy. Sentinel horses and chickens, wild birds and mosquitoes were sampled and tested for the presence of USUV and USUV antibodies within the WND National Surveillance plan. Seroconversion evidenced in sentinel animals proved that in these two years the virus has circulated in Tuscany, Emilia Romagna, Veneto and Friuli Venezia Giulia regions. In Veneto USUV caused a severe blackbird die-off disease involving at least a thousand birds. Eleven viral strains were detected in organs of 9 blackbirds (52.9%) and two magpies (0.5%) originating from Veneto and Emilia Romagna regions. USUV was also detected in a pool of Culex pipiens caught in Tuscany. According to the alignment of the NS5 partial sequences, no differences between the Italian USUV strains isolated from Veneto, Friuli and Emilia Romagna regions were observed. The Italian North Eastern strain sequences were identical to those of the strain detected in the brain of a human patient and shared a high similarity with the isolates from Vienna and Budapest. Conversely, there were few differences between the Italian strains which circulated in the North Eastern regions and the USUV strain detected in a pool of C. pipiens caught in Tuscany. A high degree of similarity at both nucleotide and amino acid level was also found when the full genome sequence of the Italian North Eastern isolate was compared with that of the strains circulating in Europe. The North Eastern Italian strain sequence exhibited 97% identity to the South African reference strain SAAR-1776. The deduced amino acid sequences of the Italian strain differed by 10 and 11 amino-acids from the Budapest and Vienna strains, respectively, and by 28 from the SAAR-1776 strain. According to this study two strains of USUVs are likely to have circulated in Italy between 2008 and 2009. They have developed strategies of adaptation and evolution to spread into new areas and to become established.  相似文献   
32.
Crown gall disease of grapevine, caused by Agrobacterium tumefaciens, often results in severe economic loss to grape production worldwide. This study demonstrated the ability of the endophytic bacteria Pseudomonas sp. Sn48 and Pantoea sp. Sa14 isolated from domesticated and wild grapevines to induce resistance in both above- and belowground tissues of grapevines infected with A. tumefaciens. Our results provide evidence that both strains can colonize roots and/or shoots. We showed that the strains Pseudomonas sp. Sn48 and Pantoea sp. Sa14 are capable of inducing stilbenic phytoalexin production in grapevine tissues and to further prime plantlets for enhanced phytoalexin production after A. tumefaciens inoculation. We also showed that in the majority of treatments, polyamine accumulation remained unchanged or slightly increased in plantlets treated with Pseudomonas sp. Sn48 and Pantoea sp. Sa14 compared with the control. Our findings indicated that the levels of polyamines remain unchanged or significantly decrease in plantlets treated with endophytic bacteria after A. tumefaciens challenge compared to the control and plantlets treated with individual endophytic bacterial strains. PR1, PR2, and PR4 gene expression levels of plantlets treated with Pseudomonas sp. Sn48 and Pantoea sp. Sa14 significantly increased after A. tumefaciens inoculation. The findings revealed the efficacy of the selected endophytic bacteria in triggering grapevine resistance against A. tumefaciens and the possible use of these strains as an alternative to chemical control methods in grapevine crown gall disease management.  相似文献   
33.
During banana processing, knowledge of the mechanical properties of bananas is very important. To determine these mechanical properties, a shear-pressure loading test was used with three moisture content levels, three velocities for lowering the lever during the test, and two methods of placement in the pressure test with the force-deformation diagram and extracting from it. In the shear test, there was a significant relationship between the moisture content effect and the three mechanical properties. The maximum and minimum amounts of failure stress at the moisture content levels of 85.39% and 65.58% for the side and the internal arc of the banana placement methods occurred, respectively. Additionally, the maximum and minimum failure strain amounts at a moisture content of 71.64% for the second and first placement occurred, respectively. The maximum and minimum modulus of elasticity at the moisture content levels of 85.39 w.b.% and 71.64 w.b.% for the first and second placement occurred.  相似文献   
34.
A 2‐month trial was conducted to record the effect of citric acid and phytase supplementation on growth performance and nutrient digestibility in labeo rohita. Nine treatment (T) diets having 0, 500 and 1,000 FTU/KG phytase and 0, 15 and 30 g/kg citric acid were prepared and were designated as T1, T2, T3, T4, T5, T6, T7, T8 and T9 diets. There were three replicates for each of the test diets. Fish samples (n = 324) were stocked in different tanks and were fed with T1, T2, T3, T4, T5, T6, T7, T8 and T9 diets. Significant (< .05) increase in growth parameters, apparent digestibility of dry matter, crude protein, crude fat, gross energy and minerals (Na, K, Fe, Mg, Mn, Zn) was recorded in fish fed with T9 diets.  相似文献   
35.
This study was conducted to estimate the spatial distribution of penetration resistance (PR), Proctor maximum bulk density (MBD) and critical water content (CWC) as soil mechanical indices. Soil samples to determine sand, silt, clay, organic carbon (OC), CaCO3, bulk and particle density, total porosity, field water content, MBD and CWC values were collected. Field measurements of PR at 0–10 cm depth were taken from 105 geo-referenced points with 3000 × 3000 m intervals in agricultural lands of Ardabil plain, Iran. Ordinary kriging (OK) and inverse distance weighting (IDW) methods were used to analyze spatial variability of PR, MBD and CWC. The strongest spatial dependences with the lowest ranges of influence were found for OC (7560 m) and MBD (8370 m). The models of fitted semivariograms were Gaussian for PR and MBD, and exponential for CWC. The moderate spatial dependences with the ranges of 13,300 and 40,100 m were found for CWC and PR, respectively. The best prediction according to Lin’s concordance correlation coefficient was obtained by OK for PR (0.48) and IDW for MBD (0.09) and CWC (0.03). These results can be applied in programming of optimum tillage operations for reducing soil compaction risk in the studied region.  相似文献   
36.
This work describes the first outbreak of streptocariasis by Streptocara incognita reported from Italy. The disease was observed in a backyard flock of 62 ducks (Cairina moschata domesticus) located in Treviso, northeastern Italy. Fifteen birds died in a period of 2 wk, showing debilitation and emaciation. Two ducks were submitted for postmortem examination and an esophagitis associated with nematodes was observed. The nematodes were identified as Streptocara incognita.  相似文献   
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