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1.
In 2004 the banded greenhouse thrips,Hercinothrips femoralis (Reuter) (Thysanoptera: Thripidae), was recorded for the first time in greenhouse-grown organic banana in the area of Sitia (northeastern Crete). Banana fruits were severely damaged by the thrips infestation and a typical smoky-red discoloration of the fruit was observed. Pest control was poor using either high-pressure washing with potassium fatty acids, or commercially available thrips predatorsNeoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) andOrius laevigatus (Fieber) (Hemiptera: Anthocoridae). During 2005H. femoralis was also found causing severe damage in conventional banana plantations in Arvi, the main banana-growing area of Crete. http://www.phytoparasitica.org posting Sept. 17, 2006.  相似文献   
2.
In 2010, a West Nile virus (WNV) epidemic was reported in Central Macedonia, Northern Greece, with 197 neuroinvasive disease (WNND) cases in humans. The following 3 years, WNV spreads to new areas of Greece and human cases reoccurred during the transmission periods. After the initial outbreak, a WNV surveillance system using juvenile backyard chickens was established in Central Macedonia (after the 2011 outbreak) and Eastern Macedonia‐Thrace (after the 2012 outbreak). Sera were screened for the presence of antibodies against WNV using cELISA and serum neutralization test, to monitor the spread of WNV and to assess the correlation between the WNV point seroprevalence in chickens and the incidence rates of human WNND cases in the aforementioned areas. WNV seroprevalence in chickens was 10.4% (95% CI: 7–15) in Central Macedonia (2011) and 18.1% (95% CI: 14–23) in Eastern Macedonia‐Thrace (2012). Seroprevalence in chickens and incidence rates of human WNND cases in Eastern Macedonia‐Thrace were strongly positively correlated (ρ = 0.98, P = 0.005) at the regional unit level, with the incidence of WNND in humans increasing with increasing WNV point seroprevalence in chickens. In Central Macedonia, the correlation was weaker (ρ = 0.68, P = 0.20), apparently due to small number of reported human WNND cases. Another study was also conducted using juvenile backyard chickens in Central Macedonia, aiming to detect early WNV enzootic circulation, before the onset of human cases during 2011 and 2013. The first seroconverted chickens were detected about 1.5 months before the laboratory diagnosis of any human WNND cases in Central Macedonia, for both years. WNV surveillance, using juvenile backyard chickens, was reliable for the identification of areas with WNV enzootic and silent transmission, and for early warning. Timely diffusion of information to public health authorities facilitated the successful implementation of preparedness plans to protect public health.  相似文献   
3.
The commercial fish industry in Greece traditionally represents one of the most important natural resource-based industries. The process by which the wide variety of seafood products moves from the deck of a trawler, or the fish farm, to the consumer's dish is rather complicated. Considering the various species marketed, the seasonal nature of the many domestic and foreign supplies, the specific quality and safety attributes, and a multitude of processing methods and products, the effective marketing of seafood products becomes very demanding. The present survey evaluates the Greek consumers' attitude towards wild and farmed fish in order to understand and satisfy market needs. The results of this study mainly indicate that fish consumption pattern is age-dependent. In addition, four consumer clusters are identified, with clear-cut socio-demographic profiles.  相似文献   
4.
  1. Marine aquaculture, and its fast-growing development, has the potential for wider environmental, ecosystem, and biodiversity impacts. This study assesses the impact of fish farming on a bottlenose dolphin (Tursiops truncatus) population within the Gulf of Ambracia (western Greece) between 2007 and 2018. Two different study areas were defined in order to investigate differences on occurrence, abundance, behaviour, and seasonal fluctuations between them: a ‘control area’, in the north-western side of the Gulf; and a ‘fish farm area’, in the south west, where the highest density of fish farm cages is found.
  2. A total of 169 daily surveys were dedicated to the control area and 74 days were dedicated to the fish farm area, yielding 104 and 37 sightings, respectively. Both the probability of detecting dolphins (U = 6,763.000, P = 0.002) and the group sizes (U = 578.000, P < 0.001) were smaller around fish farms.
  3. Seasonality analyses were restricted to 2007–2008, as this was the period with year-round effort. Results revealed that dolphins were more frequently seen around fish farms in the winter (Kruskal–Wallis test, P = 0.036).
  4. From the 40 identified individuals that were re-sighted at least 10 times during the study period, 21 used the fish farm area less than expected according to sampling effort, and 10 of them were never observed in that area (binomial test, P < 0.05).
  5. The results revealed an impact of fish farms on the distribution of bottlenose dolphins in the Gulf of Ambracia. This information should be taken into consideration when defining ecosystem-based management measures within the management plan, which is currently in preparation for this Natura 2000 site.
  相似文献   
5.
Optimum in vitro germination of pollen grain of the avocado cultivars Fuerte, Nabal, Ettinger, Bacon and Zutano occurred at 25 °C. However, there were significant differences between cultivars in percentage germination and relative humidity (RH) requirements for optimum pollen grain growth. The most sensitive cultivar to relative humidity was Fuerte, in which the germination of pollen grain rose from 11.4%, at 40% RH, to about 50%, after one hour at 100% RH. The germination% of Nabal pollen grain was already high at 40% RH and was not increased by higher relative humidity. Increased relative humidity also helped to sustain the viability of avocado pollen. At 30 °C and 5% RH the pollen grains of Fuerte quickly lost its ability to germinate, at 40% RH for 1 hour, germination was reduced spectacularly compared to pollen kept in saturated with moisture environment where it was not affected the first 24 hours. The effects of temperature and relative humidity on fruit-set and yield of avocado are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
6.
Summary This paper reports the results of a survey of the occurrence of vesicular-arbuscular mycorrhizas and spores of the associated fungi in a variety of soils in Northern Greece. The roots of several crop species were examined for the presence of mycorrhizal structures and all samples showed evidence of infection, though to varying degrees. Cotton plants, in particular, had heavy arbuscular infection. Intact and presumably viable spores were relatively infrequent and empty non-viable spores were much more common. Soil characteristics at each sample site are reported also, but only broad generalizations are made at this stage with respect to correlations between mycorrhizal occurrence and edaphic factors.  相似文献   
7.
Forest fire risk estimation constitutes an essential process to prevent high-intensity fires which are associated with severe implications to the natural and cultural environment. The primary aim of this research was to determine fire risk levels based on the local features of an island,namely, the impact of fuel structures, slope, aspects, as well as the impact of the road network and inhabited regions. The contribution of all the involved factors to forest fires ignition and behavior highlight certain regions which are highly vulnerable. In addition, the influence of both natural and anthropogenic factors to forest fire phenomena is explored. In this study, natural factors play a dominant role compared to anthropogenic factors. Hence essential preventative measures must focus on specific areas and established immediately. Indicative measures may include: the optimal allocation of watchtowers as well as the spatial optimization of mobile firefighting vehicles;and, forest fuel treatments in areas characterized by extremely high fire risk. The added value of this fire prediction tool is that it is highly flexible and could be adopted elsewhere with the necessary adjustments to local characteristics.  相似文献   
8.
Background, aims, and scope  Sediments and soils in coastal areas are frequently polluted by anthropogenic contaminants as the result of both riverine or terrestrial discharge and autochthonic marine emissions. In order to determine petrogenic contamination in the coastal industrial area of Kavala City in northern Greece, a combination of polycyclic aromatic hydrocarbon (PAH) and organic geochemical petroleum biomarker analyses has been performed on marine and freshwater sediments as well as soils. Materials and methods  Soils, freshwater, and marine sediments have been treated by standard extraction methods. The dried and desulphurized sample extracts have been fractionated by column chromatography, followed by addition of surrogate standards. Qualitative and quantitative data were obtained by gas chromatograph connected with a flame ionization and electron capture detector (GC-FID/ECD) and by GC linked to a mass spectrometer (GC/MS), whereas identification of compounds was based on EI+-mass spectra and gas chromatographic retention times. Quantitative data were obtained by integration of specific ion chromatograms. Results  The total PAH concentrations measured in the area varied highly, showing different levels from 18 up to 318,000 ng g−1 dry weight (dw). Several PAH ratios, as well as the ratio of pristane (Pr) to phytane (Phyt), have been considered. Out of 39 samples, 22 revealed a specific distribution of hopane fingerprints indicating petrogenic input. Finally, in numerous samples, the ratio of 17α(H)-22,29,30-trisnorhopane (Tm) and 18α(H)-22,29,30-trisnorhopane (Ts) was calculated, as well as the ratio of 22S-17α(H),21β(H)-30 homohopane (αβC31-hopane 22S) and 22R-17α(H),21β(H)-30 homohopane (αβC31-hopane 22R). Discussion  Based on the specific PAH ratios, a group of samples was clearly characterized to be contaminated dominantly by combustion-derived emissions, whereas a second group of samples exhibited mixed influence from petrogenic and pyrogenic PAHs. On the other hand, the exhibition of specific hopane fingerprints in many samples indicates a direct petrogenic input. Finally, the values of the ratio of Tm/(Ts + Tm) and of αβC31-hopanes 22S/(22S+22R)-isomer demonstrated an input of highly mature organic matter that has to be clearly attributed to petroleum-derived contamination, while the ratio of Pr/Phyt showed that most samples exhibited an input of organic matter. Conclusions  The coastal area of Kavala is strongly affected by anthropogenic contaminants. Petrogenic emissions were pointed out firstly by PAH analyses that separated dominantly pyrogenic contaminated sites from areas affected by both pyrogenic and petrogenic emissions. However, analyses of organic geochemical biomarkers revealed a much higher sensitivity in identifying petroleum-derived contaminations and were successfully used to differentiate several petrogenic contaminations in the marine and terrestrial samples. Recommendations and perspectives  Based on this study, it was recommended to use a complementary approach of source-specific substances to successfully characterize petrogenic emissions. Generally, a PAH-based source identification of petrogenic versus pyrogenic contaminations should be combined with petroleum biomarker analysis. PAH and biomarker ratios as well as individual biomarker fingerprints revealed a more comprehensive view on the quality and quantity of petrogenic emissions in sediments and soils.  相似文献   
9.
10.
From May 2007 to May 2008 we have examined by otoscopy a total number of 214 cats, aged between 0 and 6 months, brought in for their first veterinary examination to a private veterinary clinic. All cats were of urban origin. In all positive cats we performed a washing of the ear using warm paraffin oil in order to determine intensity of infection. Statistical analysis was performed using the Chi-square test. A total number of 30 cats were found to be infected with Otodectes cynotis (prevalence 14.02%). Prevalence of infection was significantly (p < 0.05) higher in cats aged between 3 and 6 months (17.58%) than in cats aged below 3 months (11.38). Intensity of infection ranged between 7 and 85 (mean intensity 35.60) mites per infected cat. The same age group of cats between 3 and 6 months had significantly (p < 0.05) higher mean intensity (47.19) compared to cats aged under 3 months (22.36). No statistical significance was found between males and females for neither prevalence nor intensity. Differences and similarities with other studies are discussed.  相似文献   
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