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81.
Potential impact of weedy Brassicaceae species on oil and meal quality of oilseed rape (canola) in Australia 下载免费PDF全文
Brassicaceae weeds are a widespread problem in Australian oilseed rape crops. The weeds not only compete for resources during crop growth, but also have the potential to reduce both oil and meal quality of the harvested crop. This study investigated oil and meal quality of weedy species from the Brassicaceae family that were collected throughout cropping regions of Australia. Eighty‐nine lines from 19 species were grown and evaluated in the same environment for their potential to contaminate Australian oilseed rape seed lots. Seed and flowering characteristics of each species were also examined. The glucosinolate concentration of most of the weedy species was greater than 100 μmol g?1 of oil‐free meal, well above the threshold for meeting oilseed rape quality. Erucic acid content of 18 of the 19 weedy species also exceeded the oilseed rape quality standard of less than 2% erucic acid. This study highlights the potential of the weedy species to reduce the quality of Australian oilseed rape crops. 相似文献
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Artashes R. Khachatryan Tamara B. Wills Kathleen A. Potter 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):257-260
Abstract: A 1‐year‐old, castrated male, mixed‐breed dog was presented for sporadic episodes of kyphosis, tremors, and vocalizing. On neurologic examination, the lesion was localized to spinal cord segments T3–L3. Magnetic resonance imaging of the spine showed an expansile mass occupying most of the ventral aspect of the spinous process of T6. Fine‐needle aspirates of the mass were examined cytologically. A moderately cellular population of pleomorphic spindle cells and abundant mucinous matrix were observed. The cytologic diagnosis was spindle cell neoplasia, with myxosarcoma and fibrosarcoma as the primary differential diagnoses. The dog was euthanized. Histopathologic evaluation of the mass and surrounding tissue confirmed a low‐grade spindle cell sarcoma, with severe compressive myelopathy and mild neutrophilic inflammation. The neoplastic cells stained positive for mucopolysaccharides with Alcian blue, resulting in a final diagnosis of low‐grade (grade 1) myxosarcoma. Fine‐needle aspiration was useful in making a preliminary diagnosis of myxosarcoma in this case. Myxosarcoma should be included in the differential diagnosis for a vertebral mass in a young dog. 相似文献
84.
BACKGROUND: The presence of bed bug populations resistant to pyrethroids demands the development of new control tactics, including the use of insecticides with new modes of action. Insecticides that disrupt oxidative phosphorylation in insect mitochondria can be an option. Laboratory assays were used to measure the toxicity of chlorfenapyr to susceptible strains and two strains highly resistant to pyrethroids. The effectiveness of two chlorfenapyr‐based formulations was compared, and behavioral responses of bed bugs to dry residues of aerosol sprays were evaluated. RESULTS: Chlorfenapyr was effective against all bed bug strains, killing them at a similar rate, regardless of their susceptibility status to pyrethroids. Dry residues aged for 4 months were as toxic as fresh dry residues. The aerosol formulation had contact activity and caused faster mortality than a water‐based formulation. Bed bugs did not avoid resting on surfaces treated with aerosol. CONCLUSION: Chlorfenapyr is an option for controlling pyrethroid‐resistant bed bugs. While it does not cause quick knockdown, its long residual activity and no avoidance behavior of bed bugs to dry residues appear to make this insecticide suitable for bed bug control. A faster insecticidal effect is obtained with the aerosol formulation, suggesting greater bioavailablity of the toxicant. Copyright © 2010 Society of Chemical Industry 相似文献
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F. Kidd C. West D. G. Griffiths N. A. Potter 《The Journal of Horticultural Science and Biotechnology》2013,88(3):179-191
The volatile oil contents of dried leaves of Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris reached maximum values in summer. Different harvest dates are required in order to obtain the highest yields of dried leaves ha-1, the highest levels of volatile oil in the dried leaves, and the highest yields of volatile oil ha-1. The upper parts of balm, oregano and sage plants yielded the most dried leaves, but the lower parts showed the highest levels of volatile oil in the dried leaves. 相似文献
87.
A total of 763 faecal samples were collected from western grey kangaroos (Macropus fuliginosus) in Western Australia and screened for the presence of Cryptosporidium by PCR at the 18S ribosomal RNA (rRNA) locus. Samples that were positive at the 18S locus were also amplified at the actin locus. The overall prevalence was 9.3% (71/763). At the 18S rRNA locus, sequences were obtained for 28 of the 71 positives. Sequence analysis identified four species; Cryptosporidium fayeri in seven isolates, Cryptosporidium marcopodum in four isolates, Cryptosporidium xiaoi in six isolates and a novel genotype (kangaroo genotype I) in eleven isolates. Analysis at the actin locus confirmed the genetic distinctness of the novel genotype. The results of the present study indicate that in addition to C. fayeri and C. marcopodum, kangaroos may be capable of being infected with a wider range of Cryptosporidium species and genotypes including livestock species such as C. xiaoi. The novel genotype identified in the kangaroos most likely represents a cryptic species that requires further analyses to confirm its species status. 相似文献
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Water, Air, &; Soil Pollution - The flux of metals at the tidal limits of major rivers are an important metric of freshwater contaminant transfer to marine habitats, reported in Northeast... 相似文献
90.
A disorder of Michigan potatoes tentatively called speckle leaf is associated, in part, with air pollution injury. The disease is characterized by reduced yields following early vine maturity, premature vine death, and yellowing of the lower leaves. Necrotic spots developed on the upper surface of leaves, followed by bronzing, and upward leaf rolling. Severely affected leaves became chlorotic and remained attached to the stem. Potato plants were grown in two plastic houses through which was blown either ambient field air or ambient air filtered through activated charcoal. Plants grown in the plastic house receiving ambient air developed symptoms similar to nearby field plants. Plants grew normally in filtered ambient air and remained free of speckle leaf and air pollution injury symptoms. The potato varieties Haig, Norchip, and Superior were most sensitive, Sebago was intermediate, and Kennebec and Katahdin were most tolerant. Tobacco plants in ambient non-filtered air developed symptoms typical of ozone injury. Bean leaves became bronzed with brown necrotic flecks on both surfaces, and severely affected leaves dropped. Neither tobacco nor bean was affected in the filtered air. 相似文献