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911.
Abstract

Oil products are widely used in orchards and on grapevine as pesticides, or adjuvants to pesticides. We aimed to get information on the efficacy of formulated rape seed oil against phytophagous mites in grapevine and its effect on predatory mites. Formulated rape seed oil (TELMIONR) from the Temmen GmbH, Germany was used in field trials at 0.5% and 1 %.

For phytophagous mites TELMIONR had an efficacy of 90,1% and 91,2% for 05% and for 1%, respectively. For Phytoseiidae there was no side effect at 0.5% and 1%. For Tydeiidae there was no side effect at 0.5% and a moderate toxicity (43.1%) at 1%. On the basis of our results TELMIONR seems to fit well into Integrated Pest Management or Organic Production in grapevine.  相似文献   
912.
The effect of ozone fumigation on the reduction of difenoconazole residue on strawberries was studied. Strawberries were immersed in 1.0 L of aqueous solution containing 400 μL of the commercial product (250 g L?1 of difenoconazole) for 1 min. Then, they were dried and exposed to ozone gas (O3) at concentrations of 0.3, 0.6 and 0.8 mg L?1 for 1 h. The ozone fumigation treatments reduced the difenoconazole residue on strawberries to concentrations below 0.5 mg kg?1, which corresponds to a 95% reduction. The strawberries treated with ozone and the control group, which was not treated with ozone, were stored at 4°C for 10 days. Some characteristics of the fruit were monitored throughout this period. Among these, pH, weight loss and total color difference did not change significantly (P > 0.05). The fumigation with ozone significantly affected the soluble solids, titratable acidity and ascorbic acid content (vitamin C) of the strawberries preventing a sharp reduction of these parameters during storage.  相似文献   
913.
EC Directive 2008/50/CE on ambient air quality and cleaner air for Europe specifies the obligations of Member States regarding fixed measurements of atmospheric pollutants in areas where maximum concentration levels exceed the lower assessment threshold. However, indications as to the siting of atmospheric monitoring stations are less precise and sometimes confusing. Campaigns to measure benzene and other volatile organic compounds in Murcia in 2007 and 2008 revealed that the areas where measurements coincided with the mean concentration for the whole city were always practically the same. Consequently, we propose a method for siting atmospheric monitoring stations in cities for which emission sources remain steady throughout the year, as is the case for cities in most southern European countries, where the most important emission source is traffic. The method is particularly useful for towns in which only one fixed measuring point is compulsory and should help local authorities in making correct decisions in this context.  相似文献   
914.
In Brazil, sugar-cane crops are burned to facilitate harvesting, and this causes environmental pollution from the large amounts of smoke and soot that are released into the atmosphere. The smoke and soot contain numerous organic compounds such as PAHs. In this study, PM10 and PAH concentrations in the air of Araraquara (SE Brazil, with around 200,000 inhabitants and surrounded by sugar-cane plantations) were determined during the harvest and non-harvest seasons. The sampling strategy included two campaigns in each season, with 20 samples per season. PM10 was collected using a Hi-vol sampler with Teflon? – coated glass fiber filters. PM10 ranged from 41 to 181 μg m?3 during the harvest season, and from 12 to 47 μg m?3 during the non-harvest season. The mean total concentration of PAHs was 2.5 ng m?3 (non-harvest season) and 11.6 ng m?3 (harvest season). In all sampling periods, the most abundant polycyclic aromatic hydrocarbons were phenanthrene and fluoranthrene, and the least abundant was anthracene. The cluster analysis of the total PAH concentrations for each day of sampling and the corresponding meteorological data suggested that the atmospheric concentration of PAHs was independent of the differences in the weather between the seasons. For both sampling seasons, the statistical treatment (PCA, Varimax rotation and HCA) indicated the presence of vehicle sources (diesel, gasoline, and natural-gas engines); but for the harvest season, the main source was attributed to sugar-cane burning. The data generated by this study indicated the burning of sugar-cane as the main contributor to the high levels of PAHs detected in samples during the sugar-cane harvest season.  相似文献   
915.
Huge quantities of discarded fruits generated from greenhouse crops represent a worldwide environmental problem. The aim of this work was to assess the efficiency of vermicomposting as a recycling management option for biotransforming tomato-fruit wastes from greenhouses into an organic nutrient-rich product available for agricultural purposes. A pilot vermireactor was constructed. It was provided with a manure layer, where an initial population of Eisenia fetida was introduced and fed continuously at a high organic loading rate (13.6 kg TOC m?3 wk?1) for 150 days. Vermicompost chemical and enzymatic parameters as well as the bacterial and fungal community structure were determined for 210 days (vermicomposting plus a maturation period). Earthworm biomass increased after 90 days, and then declined due to increasing pH, electrical conductivity and ammonium concentration. The temporal patterns of dehydrogenase, β-glucosidase, protease and urease were related to earthworm growth and the stabilization of organic matter. Bacterial DGGE profiles differed between the period of degradation of labile substrates and the maturation step. Fungal communities at the stage of maximum earthworm biomass differed most, suggesting a gut passage effect. The end product was chemically stable and enriched in nutrients, demonstrating that tomato-fruit wastes can be successfully vermicomposted into a valuable soil amendment. We suggest continuous-feeding vermicomposting as an environmentally sound management option for greenhouse wastes.  相似文献   
916.
917.
Environmental Science and Pollution Research - We have demonstrated the potential leaching of eight compounds, one insecticide (flonicamid) and seven fungicides (myclobutanil, penconazole,...  相似文献   
918.
Environmental Science and Pollution Research - Chlorine is considered the most used chemical agent for water disinfection worldwide. However, water chlorination can lead to by-product generation...  相似文献   
919.
Representative samples of the following biowastes typically generated in Castilla La Mancha (Spain) were composted using a pilot-scale closed rotary drum composting reactor provided with adequate control systems: waste from the olive oil industry (olive mill waste; OMW), winery–distillery waste containing basically grape stalk and exhausted grape marc (WDW), and domestic sewage sludge. Composting these biowastes was only successful when using a bulking agent or if sufficient porosity was supported. OMW waste composting was not possible, probably because of its negligible porosity, which likely caused anaerobic conditions. WDW was successfully composted using a mixture of solid wastes generated from the same winery. SS was also successfully composted, although its higher heavy metal content was a limitation. Co-composting was an adequate strategy because the improved mixture characteristics helped to maintain optimal operating conditions. By co-composting, the duration of the thermophilic period increased, the final maturity level improved and OMW was successfully composted. Using the proposed reactor, composting could be accelerated compared to classical outdoor techniques, enabling easy control of the process. Moisture could be easily controlled by wet air feeding and leachate recirculation. Inline outlet gas analysis helped to control aerobic conditions without excessive aeration. The temperature reached high values in a few days, and sufficient thermal requirements for pathogen removal were met. The correct combination of biowastes along with appropriate reactor design would allow composting as a management option for such abundant biowastes in this part of Spain.  相似文献   
920.
Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is a serious pest of corn in several American countries. It is mainly controlled with synthetic insecticides. The objectives of this study were to evaluate the effects of the natural products, neem oil and pyroligneous extract, and the synthetic insecticide, lufenuron, at 2.50mL water (0.25 %) on the mortality of 2-, 4- and 6-day-old caterpillars of S. frugiperda, and their selectivities against fourth instar larvae of Eriopis connnexa Germar (Coleoptera: Coccinellidae). Four- and 6-day-old S. frugiperda caterpillars showed higher mortality after exposure to neem oil (83.33 ± 0.83 and 89.58 ± 0.90 %, respectively) and lufenuron (95.83 ± 0.96 and 85.41 ± 0.83 %), compared to pyroligneous extract (68.75 ± 0.69 and 31.25 ± 0.31 %). The deleterious effect of pyroligneous extract was higher in 2- (83.33 ± 0.83 % mortality) and 4-day-old (68.75 ± 0.69 %) S. frugiperda caterpillars than in 6-day-old caterpillars (31.25 ± 0.31 %). Larval mortality of the predator E. connexa was lower with neem oil and pyroligneous extract (25.00 ± 0.33 %) than with lufenuron (91.66 ± 1.22 %). Neem oil is thus recommended for control of S. frugiperda because of its high toxicity, combined with its relatively low toxicity to larvae of the natural enemy E. connexa.  相似文献   
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