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111.
Plant Foods for Human Nutrition - In the past few years, evidence has supported the role of plants as a valuable tool for the development of promising therapeutic support options for many diseases,...  相似文献   
112.
This paper investigates the impact of outsourcing on the labor productivity of firms in a specific local production system. A number of hypotheses about the location‐specific effects of outsourcing are put forward and tested on a sample of firms in the province of Reggio Emilia (within the Emilia‐Romagna region, in North‐East Italy). The relationship between outsourcing and productivity turns out positive only if considering the externalization of high value‐added activities. On the contrary, it is negative in the case of low value‐added activities. This occurs to a greater extent for firms in mature industrial districts, whose socio‐economic conditions however do not arrive to magnify the productivity premium of externalizing high value‐added ones. The technological innovativeness of the firms instead helps with that, pointing to a developmental use of outsourcing in the area.  相似文献   
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During the growing seasons 2007 and 2008, 210 isolates of yeasts or yeast-like fungi were obtained from the carposphere of temperate fruit collected from organic orchards in Northern Italy. Through six rounds of in vivo screening, three isolates showing the highest biocontrol efficacy against Monilinia laxa on peaches were selected. By using molecular and morphological tools, the strain AP6 was identified as Pseudozyma fusiformata, the strain AP47 as Metschnikowia sp., and the strain PL5 as Aureobasidium pullulans. This research represents the first evidence about the potential use of P. fusiformata to control postharvest diseases of fruit. By co-culturing in vitro M. laxa in the presence of the three antagonists, neither the inactivated cells nor the culture filtrate of the three isolates had any significant effect on spore germination or germ tube elongation, allowing exclusion of the production of secreted toxic metabolites. The antagonistic activity of A. pullulans PL5 and P. fusiformata AP6 was dependent on the cell concentration. Metschnikowia sp. AP47 significantly inhibited spore germination at the three concentrations tested (106 cells/mL, 107 cells/mL, and 108 cells/mL). The efficacy of the three strains was tested on peaches stored at three different temperatures, and their effectiveness was higher at 1 °C than at 8 °C or 20 °C. In trials carried out in semi-commercial conditions with peaches inoculated by spraying 105 spores/mL of M. laxa and stored for 21 d at 1 °C and 96% RH, a cell concentration effect on the control of brown rot incidence was observed. AP6 and PL5 showed no significant differences in efficacy when applied at 1 × 108 cells/mL or at 1 × 107 cells/mL, indicating that they could be used at a lower concentration in potential biofungicide formulations. Finally, in an experiment in semi-commercial conditions on fruit not inoculated with the pathogen with 21 d storage at 1 °C and 96% RH, the evaluation of postharvest quality parameters, including firmness, total soluble solids, ascorbic acid content, and titratable acidity, showed that none of the three screened antagonists impaired peach quality, when applied before storage. The present study identified three antagonistic microorganisms with potential exploitation as active ingredients for the development of products for postharvest control of brown rot on peaches.  相似文献   
115.
The aim of the study was to compare in vitro the stemness features of horse progenitor cells derived from bone marrow (BM-MSCs), amniotic fluid (AF-MSCs) and umbilical cord matrix (EUC-MSCs). It has been suggested that there may be a stem cell population within both umbilical cord matrix and amniotic fluid. However, little knowledge exists about the characteristics of these progenitor cells within these sources in the equine species. This study wanted to investigate an alternative and non-invasive stem cell source for the equine tissue engineering and to learn more about the properties of these cells for future cell banking. Bone marrow, umbilical cord and amniotic fluid samples were harvested from different horses. Cells were analyzed for proliferation, immunocytochemical, stem cell gene expression and multilineage plasticity. BM- and AF-MSCs took similar time to reach confluence and showed comparable plating efficiency. All cell lines expressed identical stem cell markers and capability to differentiate towards osteogenic lineage. Almost all cell lines differentiated into the adipogenic lineage as demonstrated by cytochemical staining, even if no adipose gene expression was detectable for AF-MSCs. AF- and EUC-MSCs showed a limited chondrogenic differentiation compared with BM-MSCs as demonstrated by histological and biochemical analyses. These findings suggest that AF-MSCs appeared to be a readily obtainable and highly proliferative cell line from an uninvasive source that may represent a good model system for stem cell biology. More studies are needed to investigate their multilineage potential. EUC-MSCs need to be further investigated regarding their particular behavior in vitro represented by spheroid formation.  相似文献   
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After being accidentally introduced from the USA at the end of the 19th century, downy mildew caused by Plasmopara viticola (Berk. et Curt.) Berlese et De Toni became one of the most damaging diseases affecting Vitis vinifera in Europe. Downy mildew causes both direct and indirect losses and can lead to severe reduction of yield. Our understanding of the life cycle and epidemiology of P. viticola has been recently altered by molecular studies that revealed that the overwintering inoculum (i.e., the oospores) does more than initiate disease, as was previously thought. A mechanistic model was developed for predicting the entire chain of processes leading to primary infections, and this primary infection model was linked to other models of secondary infection cycles. The model for primary infections defines the length of the primary inoculum season and a seasonal oospore dose consisting of several cohorts of oospores that progressively mature. The model was evaluated by means of Bayesian analysis in both Italy and eastern Canada, and showed high sensitivity, specificity, and accuracy both for potted plants and vineyards. Fungicide applications are necessary to control downy mildew because preventive agronomic practices are not very effective, including host resistance. The use of warning systems based on weather-driven models leads to a reduction in the use and cost of chemicals and a reduction in their environmental impact.  相似文献   
118.

Rice hull burning (RHB) is a traditional cultural practice of many onion growers in San Jose City, Nueva Ecija, Philippines, mainly for weed control and increased yield. The resulting carbonized rice hull (ash) is incorporated into the soil during land preparation before transplanting of onion. Studies to evaluate the effect of RHB on the population of the rice root-knotnematode, Meloidogyne graminicola, and onion yield were conducted in a farmer's field naturally infested with the pathogen. Burning of 15-cm-deep rice hulls significantly reduced the nematode populations in the soil and increased onion yield. Increasing the thickness of rice hulls burned to 30 cm deep resulted in a yield increase of 44.2% over no RHB and 11.9% over 15-cm-deep rice hulls, while the yield increase with 15-cm-thick hulls was 28.8% over no RHB. Plots that received rice hulls 30 cm deep also produced 37.7% more large bulbs for export than those plots that received 15-cm-deep hulls, and 151.7% more than those plots with no RHB. Deep ploughing did not significantly affect nematode populations compared with standard ploughing. Organic amendment did not contribute to an increase in onion yield and has no effect on the population of rice root-knot nematode.  相似文献   
119.
In 1998–99 and 1999–2000 six trials were conducted to evaluate the effect of fungicides on Fusarium head blight in the field, on infected kernels and deoxynivalenol (DON) concentration in grain. A single application of prochloraz, tebuconazole, epoxiconazole or bromuconazole, applied to durum wheat varieties at the manufacturer's recommended dose at the beginning of anthesis stage, provided good control of the disease when infective pressure in the field was low to medium, and when the main pathogens were F. graminearum and F. culmorum. Kresoxim-methyl showed a low efficacy at controlling the disease. Tebuconazole, prochloraz and bromuconazole were effective at controlling F. graminearum and F. culmorum, while kresoxim-methyl was not effective in reducing Fusarium infected kernels. DON concentration in grain of cultivars inoculated with F. graminearum and F. culmorum was high, averaging 4.2mgkg–1 (untreated control). Tebuconazole, prochloraz and bromuconazole reduced DON concentration by 43%, while epoxiconazole was ineffective. DON concentration in kernels of naturally infected cultivars was 1.95mgkg–1, a concentration which exceeds the 1mgkg–1 maximum level of contamination allowed in the United States. Furthermore prochloraz, bromuconazole and tebuconazole applications, in the naturally inoculated trials, reduced DON concentration from 73% to 96%, while epoxiconazole showed the lowest effectiveness. Moreover, a positive linear correlation between Fusarium infected grains and the DON concentration was observed.  相似文献   
120.
Brown spot, caused by Stemphylium vesicarium, is the main fungal disease of pear in northern Italy where it may cause severe crop losses and it requires numerous fungicide applications. Monitoring work was performed by collecting fungal populations in Po valley between 1995 and 2003 in order to study the dicarboximides resistance already detected in the 1990s for procymidone as a result of control failures in field. Sensitivity tests showed that the resistant strains occur all over the monitored areas. Where present the efficacy of procymidone in field is completely lost in spite of what is observed often in other fungi. In most of the isolates (phenotype R1), S. vesicarium resistance level to procymidone (Sialex) was shown to be very high (RF≅3000) whereas it was lower towards the other dicarboximides iprodione (Rovral), vinclozolin (Ronilan) and chlozolinate (Serinal) (RF≅10). Therefore the resistance is partially crossed even if a high level of resistance was rarely observed for all dicarboximides (phenotype R2). At least two different mechanisms of resistance seem to be involved: one that may provide a moderate resistance and the other that may give a high resistance level. Monospore isolate sensitivity tests confirmed the qualitative response suggested by such high resistance factors.  相似文献   
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