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101.
The utility of polymorphism analysis was determined for differentiation of the following subspecies of the Gram-positive plant pathogenic bacterium, Clavibacter michiganensis: C. m. subsp. michiganensis, C. m. subsp. sepedonicus, C. m. subsp. insidiosus C. m. subsp. nebraskensis, and C. m. subsp. tessellarius. Specific primers designed for amplification of the housekeeping genes recA, rpoB, and rpoD generated 827-, 1037-, and 862-bp DNA fragments, respectively. PCR products obtained from 40 C. michiganensis strains were analysed using RFLP with four restriction endonucleases, and those PCR products with specific RFLP patterns were sequenced. The genotypes discriminated after PCR–RFLP were specific for each subspecies and also allowed for differentiation of C. m. subsp. michiganensis strains. Sequence analysis of the recA, rpoB, and rpoD gene fragments also distinguished C. michiganensis subspecies and was useful for phylogenetic analysis of all subspecies. For rapid, inexpensive, and effective differentiation of the five subspecies in this research, we recommend the amplification of recA and/or rpoD gene fragments and digestion of the PCR products with the restriction endonuclease FnuDII.  相似文献   
102.
Improving ways of managing disturbed areas is in urgent need of further research. We assessed the effect of two contrasting management types—salvage logging and set aside for natural regeneration—applied to a large-scale windthrow in NE Poland on two distinct taxonomic groups of animals: scuttle flies and birds. In total, 5,368 individual scuttle flies were trapped and 1,649 individual birds were recorded. In both taxonomic groups, we recorded the “winners and losers” of the effects of salvage logging. The responses of particular species in both groups were independent of their body size. Species diversity, assessed by rarefaction, increased as a result of the logging in birds and declined in scuttle flies. The species richness, corrected for unseen species of scuttle flies and birds, was higher on the managed windthrow when compared to the natural one. Comparison of the results obtained with published data from the intact stands of Białowieża Primeval Forest suggests that salvage logging reduced the similarity of the fly and bird community to those reported from undisturbed, natural forest areas. Our results concern mostly the common species. We conclude that salvage logging has considerable influence on assemblages of common species in the post-disturbance forests. Birds and flies did not respond similarly to salvage logging in term of species diversity, although both groups included species that were attracted to either managed or unmanaged windthrow sites.  相似文献   
103.
Stimulation of macrophages by a variety fatty acids causes activation of MAP kinases (MAPKs). The consequences arising from down-regulation of MAPKs may be a limitation in the activity of PPARγ, which is modulated by a modification catalyzed by these kinases. Phosphorylation of MAP kinases-ERK1/2 and p38 as well as PPARγ was determined by real-time polymerase chain reaction and Western blotting in human macrophages cultured with conjugated linoleic acids (CLAs). We demonstrated that CLA isomers alter MAP kinase phosphorylation and PPARγ activation. Phosphorylation of ERK1/2 was diminished in cells cultivated with cis-9,trans-11 CLA, whereas phosphorylation of p38 was reduced by trans-10,cis-12 CLA. PPARγ was phosphorylated mainly by ERK1/2, and consequently, PPARγ phosphorylation was suppressed mainly by cis-9,trans-11 isomer. In human adipocytes, cis-9,trans-11 C 18:2 raised the activation of PPAR and several of its downstream target genes. We suggest that a similar process may also occur in human macrophages.  相似文献   
104.
105.
Summary The reducing sugar content and chip colour were studied in diploid potatoes bred for superior table and chipping quality. The reducing sugar content in the tubers of 119 diploid clones was estimated before and after cold storage (4–6°C) in the years 1987–1991, and reducing sugar and chip colour were determined in 1990 and 1991 for 36 clones. Thirty two clones had a significantly lower reducing sugar content after cold storage than cv. Mila. The year of evaluation, storage temperature and genotype significantly affected the reducing sugar content.  相似文献   
106.
Acoustic,mechanical and microstructural properties of extruded crisp bread   总被引:1,自引:0,他引:1  
The aim of this work was to describe the texture and structure of crisp bread obtained with different extrusion parameters. The texture of different crisp bread samples was evaluated using a combination of acoustic and mechanical tests. The advantage of this measurement setup is the feasibility of simultaneous registering of the force–deformation characteristics, sounds (using an acoustic envelope detector coupled to the texture analyser with a microphone) as well as mechanical vibrations (registered using a piezoelectric sensor) generated during a penetration test. All analysed samples of bread were products with a crisp texture that emitted audible sounds with a significant intensity that could be registered with a microphone as well as with a contact method. Micro-CT cross-section images showed the highly porous structure of the crisp breads but variant 3 appeared to have thicker walls and larger cells than the other breads.  相似文献   
107.
The aim of this study was to investigate the impact of carbofuran, a carbamate pesticide on the enzymatic activity of acetylcholinesterase (AChE) in the larvae of the herring nematode parasite Anisakis simplex. A. simplex larvae collected from herring were exposed to carbofuran in vivo at concentrations of 50, 100, 500 and 1000 μg/l, for 24, 48 and 72 h, at a temperature of 4 °C. Generalized Linear Models (GLM) were applied to analyze the relationship between AChE activity and carbofuran concentration, the time of exposure and the biological parameters of the host. The results indicate that A. simplex larvae have a high threshold of sensitivity to carbofuran. The average enzymatic activity was higher in parasites obtained from male hosts, when compared with female hosts. These data suggest that host sex-dependent biological processes may also influence AChE enzymatic activity in parasites.  相似文献   
108.
Behaviour represents a reaction to the environment as fish perceive it and is therefore a key element of fish welfare. This review summarises the main findings on how behavioural changes have been used to assess welfare in farmed fish, using both functional and feeling-based approaches. Changes in foraging behaviour, ventilatory activity, aggression, individual and group swimming behaviour, stereotypic and abnormal behaviour have been linked with acute and chronic stressors in aquaculture and can therefore be regarded as likely indicators of poor welfare. On the contrary, measurements of exploratory behaviour, feed anticipatory activity and reward-related operant behaviour are beginning to be considered as indicators of positive emotions and welfare in fish. Despite the lack of scientific agreement about the existence of sentience in fish, the possibility that they are capable of both positive and negative emotions may contribute to the development of new strategies (e.g. environmental enrichment) to promote good welfare. Numerous studies that use behavioural indicators of welfare show that behavioural changes can be interpreted as either good or poor welfare depending on the fish species. It is therefore essential to understand the species-specific biology before drawing any conclusions in relation to welfare. In addition, different individuals within the same species may exhibit divergent coping strategies towards stressors, and what is tolerated by some individuals may be detrimental to others. Therefore, the assessment of welfare in a few individuals may not represent the average welfare of a group and vice versa. This underlines the need to develop on-farm, operational behavioural welfare indicators that can be easily used to assess not only the individual welfare but also the welfare of the whole group (e.g. spatial distribution). With the ongoing development of video technology and image processing, the on-farm surveillance of behaviour may in the near future represent a low-cost, noninvasive tool to assess the welfare of farmed fish.  相似文献   
109.
Products containing microorganisms (bacteria, fungi and viruses) can be used in plant production as an intervention as well as a prevention method for pest control. Their utilisation is strictly in line with the principles of integrated pest management, provided that they are effective and safe. The rules of registration of microorganisms for crop production in the European Union differ, depending on whether they are placed on the market as plant protection products or not. For over 20 years, uniform rules for registration of plant protection products have been in force. Currently, 36 microorganisms marked up to the strain are approved for use in pest control in the Community. The decision concerning market placement of plant protection products containing approved microorganisms is issued for each member state separately. The approaches to market placement of other products with microorganisms differ within the EU, ranging from a complete lack of requirements to long and costly registration procedures. © 2015 Society of Chemical Industry  相似文献   
110.
Prevention methods can still be a cost‐effective and efficient tool for pest control. Rational use of prevention methods is a feasible way to reduce dependency on chemical protection in agriculture. Costs, workload and farmers' awareness are key issues, however. In Poland, crop rotation is used as a method for pest control only to a limited extent owing to the high share of cereals in the crop structure. The choice of resistant varieties is satisfactory, but farmers should make use of qualified seed material more often. Liming is recommended on the majority of farms on account of widespread soil acidity. Favourable aspects as regards the prevention of pest development are biodiversity and the popularity of prevention cultivation techniques. © 2014 Society of Chemical Industry  相似文献   
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