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Russian olive trees (Elaeagnus angustifolia) showing witches’ broom symptoms typical of phytoplasma infection were observed in the Urmia region of Iran. A phytoplasma named Russian olive witches’ broom phytoplasma (ROWBp-U) was detected from all symptomatic samples by amplification of the 16S rRNA gene and 16S/23S rDNA spacer region using the polymerase chain reaction (PCR) which gave a product of expected length. DNA from symptomless plants used as a negative control yielded no product. The sequence of the 16S rRNA gene and 16S/23S rDNA spacer region of ROWBp-U showed 99% similarity with the homologous genes of members of the aster yellows group. We also detected a phytoplasma in neighboring alfalfa plants (AlWBp-U) showing severe witches’ broom symptoms. An 1107 bp PCR product from the 16S rRNA gene showed 99% homology with the corresponding product in ROWBp-U, suggesting the presence of the same phytoplasma actively vectored in the area. Further observations showed that Russian olive trees with typical ROWB symptoms were present in an orchard near Tehran which is located over 530 km south-east of the original Urmia site. The corresponding sequence of this phytoplasma (ROWBp-T) showed 99% homology to that of the ROWBp-U. A sequence homology study based on the 16S rRNA gene and 16S/23S rDNA spacer region of ROWBp-U and other phytoplasmas showed that ROWBp-U is most closely related to the 16SrI group. To our knowledge, this is the first report of a phytoplasma infection in a member of the Elaeagnaceae.  相似文献   
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Flavescence dorée (FD) is one of the most economically important grapevine diseases in Southern Europe, and it is associated with phytoplasmas, phloem-limited wall-less bacteria. Recovery from disease naturally occurs in infected grapevines during the following seasons after infection. The capability of the leafhopper vector Scaphoideus titanus to acquire FD phytoplasma (FDP) from recovered and infected grapevines of Barbera and Nebbiolo varieties was investigated in North-western Italy vineyards monitored from 2007 to 2011. Pathogen concentration was quantified by real-time PCR in FDP-infected grapevines and broad beans, also used as source plants under controlled conditions, to correlate acquisition capabilities and phytoplasma titre in source plants. S. titanus acquired FDP from infected, but not from recovered, grapevines. FDP titre was higher in Barbera than in Nebbiolo and higher in summer than in spring, and acquisition efficiency and pathogen titre in source plants were positively correlated, both in field and laboratory conditions. Recovered plants do not represent a source of inoculum for the vector and therefore do not contribute to FDP spread. The inability of recovered plants to serve as FDP acquisition sources for the vector as well as the effect of the season and of the two grapevine varieties on the FDP acquisition efficiency are relevant results to re-design disease management practices, especially since insecticide treatments against the vector are not fully effective, and newly designed successful control strategies are required.  相似文献   
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The concentrations of major heavy metals in organs of two cyprinid fish and in water collected from three sections of the Kor River, Iran, were determined using the induction coupled plasma method. The concentrations of heavy metals in tissue of fish from the middle sampling zone were significantly higher (p?<?0.05) than those from the other two sampling zones, whereas no significant differences (p?>?0.05) were detected between the two sexes and species. Estradiol in females and progesterone and testosterone in males from the middle study site were significantly (p?<?0.05) lower than values from the other two sites. Pathological changes in blood cells, liver, and kidneys of fishes were significantly higher in highly polluted areas (middle sampling zone). So heavy metals exposure can effectively decreases estrogenic and androgenic secretion in fish. These results show that industrial activities have polluted the river and that heavy metals exposure can induce pathological changes in fish organs.  相似文献   
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Four laboratory methods including, E-test MIC, Oxacillin screen agar, manitol salt agar plus oxacillin and CHROMagar MRSA were compared for detection of methicilin resistant Staphylococcus aureus (MRSA). CHROMagar MRSA had a high sensitivity and specificity comparing to conventional E-test method. Sensitivity and specificity by manitol salt agar was 95 and 100%, respectively, while oxacillin screening agar method had 100% sensitivity and 95% specificity.  相似文献   
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The essential oil of Oliveria decumbens was investigated for its components and antimicrobial activity against six bacteria and two fungal strains. The essential oil was characterized by a high amount of oxygenated monoterpene components of which thymol (47.06%) and carvacrol (23.31%) were the major components. The oil exhibited high antimicrobial activity against all tested Gram+ and Gram- bacteria and fungal strains.  相似文献   
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In this research, a facile and cost effective method is presented for in-situ synthesis of cuprous oxide nanoparticles on polyester fabric along with surface modification by using one pot wet chemical method at boil. Copper sulfate (CuSO4), sodium hypophosphite (SHP) and polyvinylpyrrolidone (PVP) were used as precursor, reducing agent and stabilizer, respectively. Further, monoethanolamine (MEA) was used as pH adjustment and also modifier of polyester surface introduced amide and hydroxyl functional groups on the fabric. The images of FESEM, mapping, patterns of EDX, UV-visible absorbance spectrum, FTIR analysis and X-ray diffraction pattern confirmed the successful processing. The treated samples showed excellent antibacterial properties (100 %) toward both Staphylococcus aureus and Escherichia coli pathogen bacteria. Also, the results of cytotoxicity test proved no harmful effects on the human dermal fibroblasts for the treated sample with the lower concentration of the materials having white color with good antibacterial activities. The treated samples also indicated very good UV protection properties as well as improved wettability and mechanical properties. They are also sensitive to ammonia through immediate color change when contacted with ammonia solution. The above mentioned processing method can be used for production of polyester fabric with multifunctional properties for using in the various textile industries.  相似文献   
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Modern agricultural systems have to provide enough micronutrient output to meet all the nutritional needs of people. Accordingly, knowledge on micronutrient status in soil and crop edible tissues is necessary. This study was carried out to investigate zinc (Zn), iron (Fe), manganese (Mn), and copper (Cu) concentration of calcareous paddy soil and the relative rice grain. Rice crops (straw, hull, and grain) and associated surface soils (0–25 cm) were collected from 136 fields and analyzed for total and diethylene triamine pentaacetic acid (DTPA) available Zn, Fe, Mn, and Cu. The DTPA-Zn concentration in more than 50% of paddy soils was less than its critical deficiency concentration (2 mg kg−1), while the concentrations of DTPA Fe, Mn, and Cu were sufficient. The grain Zn concentration of more than 54% of the rice samples was less than 20 mg kg−1. About 55% and 49% of the rice samples were deficient in Mn and Cu, respectively, while the Fe concentration in rice grains was sufficient. A significant negative correlation was found between the CaCO3 content and soil DTPA-extractable Zn, Fe, Mn, and Cu. There were significant relationships between the total soil phosphorus and DTPA-extractable micronutrient concentrations. By considering the average daily rice consumption of 110 g per capita, the Zn, Fe, Mn, and Cu intake from rice consumption was estimated to be 2.4, 7.7, 1.6, and 0.7 mg for adults, respectively.  相似文献   
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