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31.
Information on the mating and dispersal behaviour of the rice stem borers Scirpophaga incertulas and Chilo suppressalis is necessary for the design of resistance management strategies for rice varieties genetically engineered with toxin genes from Bacillus thuringiensis (Bt). We investigated whether S. incertulas and C. suppressalis move from the site of adult eclosion before mating to determine the likelihood that random mating will occur between adults eclosing in fields of Bt rice and refuge fields of non-Bt rice. Observations were made under laboratory, screenhouse and field conditions. Almost all S. incertulas males and females flew out of sight after cuticle expansion and hardening, as did most C. suppressalis. Approximately 15% of C. suppressalis females called and mated within 3?m of the site of eclosion, and approximately 5% of C. suppressalis males mated within 5?m of the site of eclosion. These results suggest that random mating is likely to occur between S. incertulas eclosing in Bt rice fields and nearby refuge fields. Although a small proportion of C. suppressalis did not move far before mating, random mating of moths from Bt and nearby refuge fields is also likely to occur in this species if Bt-resistant moths are rare.  相似文献   
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Routine Bovine Viral Diarrhoea Virus (BVDV) monitoring of a commercial beef herd in southern New South Wales over a 10-year period provided an opportunity to assess the impact of the introduction of BVDV on that herd. BVDV antibody testing provided strong evidence that the herd was initially free of BVDV (2009–2011). Testing from 2012 suggested BVDV had been introduced into the herd and this was confirmed in 2015 with the identification of persistently infected (PI) animals. Having become established in the herd, the owners then set out to eliminate BVDV from the herd. Antigen testing aimed at identifying PI animals revealed BVDV was already absent from the herd. Subsequent antibody testing confirmed that the herd was now free from BVDV. Despite the incursion of BVDV in this herd, there was little measurable impact on reproductive performance (pregnancy rates), although suspected increased calf losses from birth to calf marking were reported. This is the first time such self-clearance has been documented as part of a longitudinal study under Australian conditions.  相似文献   
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This paper presents the effect that the traditional cooking process of black beans (Phaseolus vulgaris, Tamazulapa variety) has on the quantity and composition of soluble (SDF) and insoluble (IDF) dietary fiber of beans, as well as on its protein digestibility and protein quality. There was an increase of IDF from 18.1% in cooked beans to 22.4% in fried beans, and a decrease in SDF from 8.4% to 6.6%, respectively. Starch content decreased from 34.5% to 31.3%. No change was found in lignin. The xylose content was higher in IDF than in SDF and decreased to some extent from cooked to fried beans. Arabinose content was similar in IDF and SDF with no change caused by processing. The fraction containing glucose, mannose and galactose in IDF was higher than in SDF, the content increasing in IDF and decreasing in SDF, with processing. Protein content in IDF was higher than in SDF, with no major change when processing. About 29.5% of the total protein of beans was bound in DF. Protein digestibility and protein quality decreased from cooked to fried beans and was positively related to IDF.  相似文献   
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Clavibacter michiganensis subsp. sepedonicus causes potato ring rot disease. The identification process for this bacterium is complex and long. This work demonstrates that the stable low-molecular-weight (LMW) RNA profiles allow their rapid identification. Staircase electrophoresis in polyacrylamide gels was used to analyze the LMW RNA profiles of 54 strains of C. michiganensis subsp. sepedonicus from different geographic origins. The profiles of several strains of other subspecies of C. michiganensis and other pathogens of potatoes were also analyzed. All the strains of C. michiganensis subsp. sepedonicus had the same LMW RNA profile. They had a band in class 2 of tRNA that was absent in the other subspecies of the species C. michiganensis. Also, the LMW RNA of C. michiganensis subsp. sepedonicus was different with respect to the LMW RNA profiles of other pathogens of potato. The results indicate the possible utilization of LMW RNA profiles in identification of the bacteria causing potato ring rot disease.  相似文献   
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BACKGROUND: An efficient delivery system for seed‐protectant chemicals is needed in light of several disadvantages of conventional seed treatment methods. This study evaluates the efficacy of film‐coat application in maintaining the persistence and potency of imidacloprid on Lycopersicon esculentum (L.) Mill. seeds after simultaneous storage under ambient and regulated environment in paper and aluminium packages. RESULTS: High‐performance liquid chromatography (HPLC) revealed 0.135 mg kg?1 of herbage material to be the threshold value beyond which absolute control was obtained, and with film coating the latter was achieved even with half‐dosage seed treatment, irrespective of the storage condition. The technique provided early protection to the crop and also nullified the deleterious effects of ambient storage on the persistence and potency of the pesticide. CONCLUSION: Film coating enabled superior pesticide dosage as well as higher biological efficacy to be achieved. Hence, in addition to being an ecofriendly alternative, the technique would be a more economically viable option for storage of treated seeds. Copyright © 2009 Society of Chemical Industry  相似文献   
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An 8-month-old German Shepherd dog was presented for investigation of pelvic limb gait abnormality. Neurolocalization indicated a T3-L3 spinal cord lesion. The myelographic appearance was of an intramedullary lesion at T9/10, but upon subsequent magnetic resonance imaging it was determined that the mass was extramedullary. A diagnosis of nephroblastoma was made on histological examination. The imaging features of this rare tumor and the differentiation of intradural-extramedullary and intramedullary masses are discussed.  相似文献   
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A Miscanthus Sinensis plantation in Galicia, Spain, provided the raw material for experimental fiberboards. After harvesting, the Miscanthus stems were cleaned and chipped. The chips were steam exploded with a thermo-mechanical aqueous vapor process in a batch reactor. The resulting material was dried, slightly milled, and used to produce fiberboard with no synthetic binders. The pretreatment and the pressing conditions that optimize the physico-mechanical responses were determined. Response surface methodology with a central composite design was used. The variables studied and their respective variation ranges were: pretreatment time, 4–14 min; pressing temperature, 195–245°C; pressing pressure, 1.9–14.6 MPa. The boards obtained were very good quality (modulus of elasticity as high as 7630 MPa, modulus of rupture as high as 61 MPa, internal bond as high as 4.1 MPa, thickness swelling as low as 2.5%, and water absorption as low as 8.9%) and more than satisfied the requirements of the relevant standard specifications.  相似文献   
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