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121.
Soares RM Lopes EG Keid LB Sercundes MK Martins J Richtzenhain LJ 《Veterinary parasitology》2011,175(1-2):168-172
Toxoplasma gondii, Hammondia hammondi, Neospora caninum, Neospora hughesi and Hammondia heydorni are members of the Toxoplasmatinae sub-family. They are closely related coccidians with similarly sized oocysts. Molecular diagnostic techniques, especially those based on polymerase chain reaction (PCR), can be successfully applied for the differentiation of Hammondia-like oocysts. In this paper, we describe a rapid and simple method for the identification of H. heydorni oocysts among other members of the Toxoplasmatinae sub-family, using a heminested-PCR (hnPCR-AP10) based on a H. heydorni RAPD fragment available in molecular database. DNA of oocysts of H. heydorni yielded a specific fragment of 289-290 bp in the heminested-PCR assay. No product was yielded when the primers were used for the amplification of DNA extracted from T. gondii, N. caninum, N. hughesi and H. hammondi, thus allowing the differentiation of H. heydorni among other members of the Toxoplasmatinae sub-family. The hnPCR-AP10 was capable of detecting H. heydorni genetic sequences from suspensions with at least 10 oocysts. In conclusion, the hnPCR-AP10 proved to be a reliable method to be used in the identification of H. heydorni oocysts from feces of dogs. 相似文献
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María M. López María José López-López Rubén Martí Javier Zamora Jesús López-Sanchez Ramona Beltra 《Potato Research》2001,44(2):197-206
Summary The efficiency of acetylsalicylic acid (ASA) in inducing localised acquired resistance against infection byErwinia carotovora subsp.carotovora was evaluated by treating potato tubers with ASA at three concentrations. Three days after treatments, tubers were inoculated
withE. carotovora subsp.carotovora by wound inoculation or by irrigation with a bacterial suspension. Experiments were performed for two consecutive years.
Statistical analysis revealed that treatment of tubers by immersion in ASA solutions at low concentrations induced a significant
reduction in the soft rot incidence. Wounding of the tubers was the most effective inoculation method and ASA at concentration
of 0.0125% (w/v), pH 7 was more efficient than at 0.025 or 0.05%. No phytotoxicity of such treatment was observed. 相似文献
124.
Berli F D'Angelo J Cavagnaro B Bottini R Wuilloud R Silva MF 《Journal of agricultural and food chemistry》2008,56(9):2892-2898
The responses of Vitis vinifera L. cv. Malbec to different solar ultraviolet-B radiation (UV-B) levels were assessed in two contrasting situations, under sunlight with full UV-B (+UV-B) and filtered UV-B (-UV-B), in three different locations at 500, 1000, and 1500 m above sea level (asl). To evaluate the effects of radiation, a simple, accurate, and rapid method for the separation and simultaneous determination of representative phenolic compounds in grape berry skins by capillary zone electrophoresis was developed. Separation was carried out in less than 20 min with 20 mM sodium tetraborate buffer containing 30% methanol, pH 9.00. The procedure is fast and reliable, and extracted grape berry skins can be directly analyzed without prior sample cleanup procedure. Berry skins from the +UV-B treatment at 1500 m asl showed the highest levels of total polyphenols anthocyanins, and resveratrol, compared with the -UV-B treatment at this altitude. 相似文献
125.
Oliveira HM Segundo MA Lima JL Grassi V Zagatto EA 《Journal of agricultural and food chemistry》2006,54(12):4136-4140
A sequential injection system for the automatic determination of glycerol in wine and beer was developed. The method is based on the rate of formation of NADH from the reaction of glycerol and NAD+ catalyzed by the enzyme glycerol dehydrogenase in solution. The determination of glycerol was performed between 0.3 and 3.0 mmol L(-1) (0.028 and 0.276 g L(-1)), and good repeatability was attained (rsd < 3.6%, n = 5) for all samples tested. The determination rate was 54 h(-1), the reagent consumption was only 0.75 micromol of NAD+ and 5.4 ng of enzyme per assay, and the waste production was 2.12 mL per assay. Results obtained for samples were in agreement with those obtained with the batch enzymatic method. 相似文献
126.
Jos�� Luis R. Gallego Carlos Sierra Albert Permanyer Ana I. Pel��ez Demelza Men��ndez-Vega Jes��s S��nchez 《Water, air, and soil pollution》2011,217(1-4):197-211
Here, we addressed biodegradation vs. volatilization processes, and also bioavailability limitations during biopile remediation of soil initially contaminated by more than 5,000 mg/kg of hydrocarbons. In order to select bioremediation strategies, we first conducted a biotreatability study, which included geochemical, textural, and microbiological characterization of the soil matrix. Next, we implemented five bioremediation approaches onsite in real-scale biopiles. In order to monitor hydrocarbon depletion and to distinguish between biological and non-biological processes, we analyzed chemical biomarkers by means of gas chromatography?Cmass spectrometry. In addition, a comprehensive study of soil grain size and its implications on bioavailability were studied. Furthermore, the evolution of microbial populations was also examined. Two of the strategies implemented in the biopiles (the combination of a slow-release fertilizer and a surfactant, and the use of an oleophilic fertilizer respectively) reduced the soil hydrocarbon content to under 500 mg/kg in 5 months. Additional results from this study indicate that volatilization was the predominant degradation process for light hydrocarbons (below 12 carbon atoms), whereas heavier compounds were mainly biodegraded. However, even in the most favorable situation, a residual concentration of hydrocarbons linked to the finer fraction of the soil was found. 相似文献
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Gilberto Santos Andrade Dirceu Pratissoli Leandro Pin Dalvi Nicolas Desneux Hugo José Gonçalves dos Santos Junior 《Journal of pest science》2011,84(3):313-320
Trichogramma spp. are major parasitoids of lepidopteran pest eggs, but there is large variation in efficacy toward a given pest among
the numerous described Trichogramma species. It is important to select the Trichogramma species that most effectively parasitize and develop in target pest eggs for biological control. In this context, Trichogramma pretiosum, T. exiguum, T. atopovirilia and T. acacioi were studied in Heliothis virescens eggs under different thermal conditions. The parasitoids were reared at constant temperatures of 20, 25 and 30°C and tested
at these respective temperatures, while parasitoids reared at 25°C were also tested at 20 and 30°C, for a total of 20 species–temperature
combinations. About 30 H. virescens eggs were offered to the parasitoids for 24 h. Among the four species, parasitism rate by T. atopovirilia was highest at all temperature conditions, whereas T. acacioi had the lowest rates of parasitism at 25°C and 25/30°C. Parasitism ranged from 13.8 to 43.8% among all species–temperature
combinations. Viability (emerged parasitoids) ranged from 80.8 to 98.4%, and was deemed satisfactory. The emergence rates
of T. exiguum and T. acacioi were affected by temperature. Temperature also affected the sex ratio of T. exiguum at 25/30°C, whereas T. pretiosum and T. acacioi produced females predominantly independent of temperature. Overall, the parasitoid T. atopovirilia was the most efficient in parasitizing H. virescens eggs, though the levels of parasitism obtained might not ensure its successful use in biological control programs. The temperature-related
differences in biological traits observed in the four Trichogramma species tested hint at the importance of making careful choices regarding climatic conditions where the parasitoid is going
to be used when selecting a species for biological control programs. 相似文献