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151.
Although most potential human pathogens (PHPs) can be inactivated during composting, the risk that such substrates represent for human health remains largely unknown due to the shortage of information on presence and abundance of PHPs in finished composts. This study focused on the assessment of Salmonella spp., Listeria monocytogenes, Shiga toxin-producing Escherichia coli (STEC), and the opportunistic fungal pathogen Aspergillus fumigatus in different compost commodities. A total of fifteen European composts, made from different waste types and processes, were evaluated for the occurrence of the selected PHPs using molecular and traditional techniques. The analyses were extended to five biochar because of their growing application in agriculture, horticulture, floriculture, and private gardening.

Enteric bacteria were detected by molecular methods in eight out of fifteen composts; however, viable propagules were confirmed for L. monocytogenes only in two composts, and for STEC in three more composts. No bacterial pathogens were found in biochar. Living A. fumigatus was present in eleven composts and two biochars. None of the eighteen isolates contained single nucleotide polymorphisms (SNPs) relevant for resistance to azole fungicides. The role of compost and biochar as a source of PHPs in the environment and the risk for human health is discussed.  相似文献   

152.
Thirty-one Phaseolus vulgaris L. and fivePhaseolus coccineus L. landraces reproduced on-farm werefound in central Italy. They were mostly grown by elderly farmers who usuallyselect for a certain type of seed. Different varieties are often grown in eachlocation and on each farm. They are maintained on-farm because of a local marketrequest for high quality products or because of sticking to traditional familyuse in cooking (21.2 and 75.8% of recorded cases, respectively). Three AFLPprimer combinations were used to assess genetic variation among collectedmaterials, a wild accession of P.vulgaris and commercial varieties of both species. Theyrevealed a quite high percentage of polymorphism (90.2% of polymorphic bands asan average). A wide genetic variation was observed among collected materials andeach accession showed a unique pattern of polymorphism. WithinP. vulgaris, landraces werediscriminated in two main subgroups, the former including the accessions fromthe Mediterranean area around the Lake Trasimeno and the latter includingaccessions from the humid Mediterranean area within the Appennine Mountains.These findings demonstrate the peculiar genetic identity of the landracesstudied also in relationship to human and environmental selection pressures.Possible on-farm conservation strategies are briefly discussed in relationshipto the information collected.  相似文献   
153.
A potato collecting expedition was carried out in the province of Jujuy, Argentina in March 24 to April 15, 2001. The objective was to collect local cultivars of potatoes and wild potato species, covering high mountain valleys not previously collected or areas where germplasm was not available. A total of 247 accessions was collected, 188 cultivated accessions of S. tuberosum subsp. andigenum, four of Solanum tuberosum subsp. tuberosum, two of S. curtilobum and 53 accessions of wild species. The wild species collected were S. acaule subsp. acaule, S. chacoense, S. infundibuliforme, S. megistacrolobum subsp. megistacrolobum, S. microdontum, S. gourlayi, S. × viirsooi and S. oplocense. Herbarium voucher specimens were obtained when possible. For the collection of cultivated potatoes, tubers were gathered from farmer's fields and in a few cases from stores or markets. Seed samples were generally obtained for the wild species. Detailed collection site data were recorded at every site. After breaking dormancy, the accessions of the cultivated species were screened for the presence of Potato virus Y (PVY), Potato virus X (PVX), Potato leafroll virus (PLRV), Potato virus S (PVS), Potato virus M (PVM), Potato virus V (PVV), Andean potato latent virus (APLV), Andean potato mottle virus (APMoV), Potato rough dwarf virus (PRDV), Potato spindle tuber viroid (PSTVd) and Spongospora subterranea f. sp. subterranea. PSTVd, APLV and PRDV were not detected, but different levels of infection are reported for the other pathogens assayed.  相似文献   
154.
An 8-y-old spayed female Beagle dog was presented with peripheral lymphadenomegaly. Lymph node cytology and flow cytometry led to the diagnosis of large B-cell lymphoma (LBCL). We detected minimal percentages of LBCL cells in peripheral blood and bone marrow samples. However, a monomorphic population of neoplastic cells different from those found in the lymph node was found in the bone marrow. T-cell acute lymphoblastic leukemia was suspected based on flow cytometric immunophenotyping. PCR for antigen receptor rearrangement (PARR) revealed clonal rearrangement of both B-cell and T-cell receptors, and the presence of both neoplastic clones in the lymph node, peripheral blood, and bone marrow. The dog was treated with multi-agent chemotherapy but died 46 d following diagnosis. Tumor staging and patient classification are needed to accurately establish a prognosis and select the most appropriate therapeutic protocol.  相似文献   
155.
Journal of Plant Diseases and Protection - Weedy forms of cultivated sunflower (Helianthus annuus) are invasive species widely distributed in several regions of the world and are commonly...  相似文献   
156.
ABSTRACT

European consumers prefer wild over farmed aquatic food and consider it healthier and tastier. Consumers are increasingly paying attention to sustainability and welfare of farmed fish. Such expectations might be met by organic certification, but this represents a cost for the producer. It is crucial to know consumer habits about farmed aquatic food consumption and willingness to pay for certification. Data about Italian consumers’ preferences regarding farmed organic aquatic food were collected by an online questionnaire. A total of 8,657 answers were analyzed, patterns associated with demographics were investigated, and the degree of correlation among answers was calculated. The majority (75%) of family units buy less than 2 kg of farmed aquatic food per month, spending on average 20–50 €. About 40% never consume organic aquaculture products because of lack of knowledge, unavailability, and high price. Slightly over half (55%) of consumers, regardless of age, sex, and area, were willing to pay a premium price for organic-certified aquatic food, seen as antibiotic free, traceable, and sustainable. Organic food in general is well known, and distrust is the main reason that consumers avoid it, while organic aquatic food is still in its infancy, and lack of knowledge is associated with low consumption.  相似文献   
157.
ABSTRACT

The study aimed to evaluate, in a marginal semi-arid Mediterranean agro-ecosystem (Sicily-Italy), the effects of arbuscular mycorrhizal fungi (AMF) inoculation and raw olive mill wastewater (OMW) (40 and 80 m3 ha?1) on forage (durum wheat-snail medick intercropping) yield, and grain production of broad bean and chickpea. AMF inoculation significantly increased (+13.6%) forage dry biomass and durum wheat nitrogen (+22.8%) and phosphorus (+32.5%) uptake. AMF inoculation, significantly promoted broad bean phosphorus uptake (+11.5%) and root nodule number (+13.9%) in the absence of OMW. OMW spreading reduced weeds in the forage (?31.3%), root nodule number (?29.7%) and dry weight (?22.7%) in broad bean. OMW also significantly increased snail medick dry biomass (+19.3%) as compared to control treatments (0, 40 and 80 m3 H2O ha?1, average production 361 g m?2), and broad bean grain yield with a production of 2.46 ± 0.12 and 1.94 ± 0.09 Mg ha?1 with and without OMW, respectively. During the experiment AMF colonization was not affected by OMW volumes. The results obtained showed that in a marginal Mediterranean agro-ecosystem: 1) OMW, notwithstanding spreading volumes, is a valuable amendment to maximize legume yield while 2) AMF inoculation is a valuable practice to improve biomass production and N and P uptake in wheat.  相似文献   
158.
Gluten aggregation properties were investigated by means of the GlutoPeak device, a viscometer recently proposed as a rapid and sensitive test for measurement of wheat flour technological performance. In this study, 62 soft wheat flour samples of different quality and end use were utilized to evaluate if the GlutoPeak parameters could adequately predict chemical and rheological characteristics of soft wheat flour dough, that is, protein content measured by the Kjeldahl method, dough strength measured by a Chopin alveograph, and dough stability and water absorption measured by a Brabender farinograph. Linear correlation analysis showed that most GlutoPeak curve parameters were strongly correlated with protein content, dough strength, and water absorption. The statistical models, obtained by a stepwise multiple regression method, showed the GlutoPeak device to be a promising tool to characterize wheat flour (Radj2 = 0.84 for protein content, Radj2 = 0.71 for dough strength, and Radj2 = 0.67 for water absorption). The rather high accuracy of the prediction models for the three mentioned parameters confirmed that GlutoPeak parameters are well correlated with other frequently used flour quality parameters and are able to describe flour technological performance.  相似文献   
159.
Hantavirus pulmonary syndrome is an emerging infectious disease caused by viruses of the genus Orthohantavirus. The rodent Oligoryzomys flavescens is distributed along four countries of South America. In Argentina, O. flavescens acts as a reservoir of three genotypes of ANDV orthohantavirus. The aims of this work were to estimate home range size and movements—with spool‐and‐line and radiotelemetry—of infected and non‐infected O. flavescens in order to understand the spread and transmission of the virus. O. flavescens use a wide area to satisfice its requirements, reaching a home range of 1.82 ha during spring. Orthohantavirus infection did not change the behaviour of individuals. We observed a great overlapping in the home range of infected and non‐infected individuals resulting in a high probability of virus dispersion on rodent population. These results show that human health risks could be high on island environments and knowledge about the movement ecology of O. flavescens provides useful information on prevention.  相似文献   
160.
European Journal of Plant Pathology - Lethal wilting was observed on young olive trees cv Favolosa in a grove in central Italy. White mycelial strands wrapped the basal portion of the stems that...  相似文献   
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