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121.
EPPO member countries requested that a study be conducted to identify and better address the risks presented by the trade of plants for planting, which has led to numerous introductions of pests into the EPPO region in recent years. Concerns were raised about the efficacy of the current plant health systems in place in the EPPO region to deal with the risks presented by plants for planting. The EPPO Study on the Risk of Imports of Plants for Planting was launched by the EPPO Council in 2010. The first part of the Study was completed in spring 2012. It was published as EPPO Technical Document 1061 ( http://www.eppo.int/QUARANTINE/EPPO_Study_on_Plants_for_planting.pdf ). Examples of pest outbreaks in the EPPO region suspected to be caused by international trade of plants for planting were analyzed. This analysis identified characteristics of the pest/crop/trade patterns associated with the risks of importing pests. These characteristics are described as criteria that are intended to be used in a screening process to enable identification of commodities that require an assessment prior to import in the EPPO region. The further elaboration of the screening process is briefly outlined.  相似文献   
122.
The efficacy of Oridermyl® (acaricidal/antibiotic/antifungal/anti-inflammatory ointment) and Revolution® (selamectin spot-on) was compared in a blinded randomized study on 24 adult cats with otoacariasis. Twelve cats were treated once daily for 10 d with Oridermyl® and 12 cats were treated on Day 0 with Revolution®. Otitis was assessed with cytological counts of mean number of bacteria and yeast on Days 0 and 10, and scored clinically every other day. All auricular secretions were removed for mite count on Day 10. On Day 0, cytological examination confirmed the presence of secondary bacterial (24/24) and fungal (21/24) infections. No live mites were observed otoscopically after Day 4 and in auricular secretions at Day 10 in both groups. On Day 10, secondary infections were resolved for all cats treated with Oridermyl® but were present in all cats treated with Revolution®. Improvement in clinical signs of otitis over time was superior in the Oridermyl® group (P < 0.001).  相似文献   
123.
Rattan, an important non-timber forest product, is a flexible palm used in weaving baskets or furniture. Rattan is light yet sturdy, making it suitable for furniture that can be moved often. Bangladesh has a large number of rattan-based enterprises. This paper reports a case study carried out in Sylhet City Corporation of north-eastern Bangladesh, exploring the production, financial profitability and marketing of rattan-based products, and the problems and priorities of rattan-based enterprises as well as their potential contribution to employment opportunity. A sample survey was conducted of 58 randomly selected rattan-based enterprises with entrepreneurs personally interviewed using a semi-structured questionnaire. Based on the total investment, the enterprises were divided into large, medium and small categories. Three origins of rattan (Local, Myanmar and Indonesia) and five species were used by the enterprises to produce 29 rattan-based product types. Rattan products were divided into three basic categories, viz. domestic utensils, domestic decorative articles and others for which uses are not specific. Among the three rattan origins, processing cost of local and Myanmar rattan species products was less and more articles were sold than for Indonesia rattan species. Financial analysis indicated that rattan-based enterprises are a profitable and attractive option for local socio-economic development. Entrepreneurs’ views on major problems and issues in rattan-based product trading and suggested measures to improve the condition of rattan-based enterprises also collected. Rattan-based enterprises will generate more domestic revenue, foreign exchange and employment if policies are adopted to provide the enterprises with a reliable source of raw materials and technical and financial assistance from Government to NGOs to sell the products, and expand market facilities in both local and international markets.  相似文献   
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Natural temperature gradient (NTG) can be a significant problem in thermal sap flow measurements, particularly in dry environments with sparse vegetation. To resolve this problem, we propose a novel correction method called cyclic heat dissipation (CHD) in its thermal dissipation probe (TDP) application. The CHD method is based on cyclic, switching ON/OFF power schema measurements and a three-exponential model, extrapolating measured signal to steady state thermal equilibrium. The extrapolated signal OFF represents NTG, whereas the extrapolated signal ON represents standard TDP signal, biased by NTG. Therefore, subtraction of the OFF signal from the ON signal allows defining the unbiased TDP signal, finally processed according to standard Granier calibration. The in vivo Kalahari measurements were carried out in three steps on four different tree species, first as NTG, then as standard TDP and finally in CHD mode, each step for ~1-2 days. Afterwards, each tree was separated from its stem following modified Roberts' (1977) procedure, and CHD verification was applied. The typical NTG varying from ~0.5 °C during night-time to -1 °C during day-time, after CHD correction, resulted in significant reduction of sap flux densities (J(p)) as compared with the standard TDP, particularly distinct for low J(p). The verification of the CHD method indicated ~20% agreement with the reference method, largely dependent on the sapwood area estimate. The proposed CHD method offers the following advantages: (i) in contrast to any other NTG correction method, it removes NTG bias from the measured signal by using in situ, extrapolated to thermal equilibrium signal; (ii) it does not need any specific calibration making use of the standard Granier calibration; (iii) it provides a physical background to the proposed NTG correction; (iv) it allows for power savings; (v) it is not tied to TDP, and so can be adapted to other thermal methods. In its current state, the CHD data processing is not yet fully automated.  相似文献   
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Leaf litter decomposition and nutrient release patterns from five common multipurpose tree species—viz., Artocarpus heterophyllus, Mangifera indica, Areca catechu, Citrus sp., and Tamarindus indica, found in homegardens of Mizoram—were evaluated using a litter bag technique. The result of the study indicates a varying pattern of decomposition and nutrient release (N&P) among the species. Citrus sp. and T. indica were found to be the most labile species with comparatively much higher decay constant and faster nutrient release. Initial nitrogen concentration, lignin content, and lignin/N ratio of foliage litter showed significantly higher (p < .01) correlation with the decay coefficient and were found to be the important determinants in the decay process. The initial slow release and immobilization of N in A. heterophyllus and M. indica leaf litter reflect their potential as a source of nitrogen storage and effective mulching material. While litter from T. indica and Citrus sp. can provide the short-term nutrient need, foliage for the other three species may supply the long-term nutrient requirement for the understory crops in such agroforestry systems.  相似文献   
129.

?Context

Understanding tree interactions requires an insight into their spatial distribution.

?Aims

We looked for presence and extent of tree intraspecific spatial point pattern (random, aggregated, or overdispersed) and interspecific spatial point pattern (independent, aggregated, or segregated).

?Methods

We established twelve 0.64-ha plots in natural bottomland hardwood stands in the southeastern USA.

?Results

Spatial point pattern analyses (Ripley’s K, L, and L 12) indicated that, when species were combined, trees were frequently aggregated and less commonly overdispersed. Plots with larger trees were more likely to exhibit overdispersion, confirming a shift to this pattern as trees grow. The intraspecific pattern of cherrybark oak and water oak was either aggregated or random. Sweetgum was aggregated on all plots and always at smaller distances (less than 5 m) than the two oak species. Intraspecific overdispersion was very rare. Interspecific segregation among the two oak species was more commonly observed (six plots) than aggregation (one plot). Cherrybark oak and sweetgum were segregated at some scale on seven of the 12 plots and aggregated on only two plots.

?Conclusion

The results from the analyses suggest that strong interspecific competition may result in segregation of trees from different species, while weaker intraspecific competition may lead to aggregations of conspecifics.  相似文献   
130.
Abstract

The effect of 0.2% emamectin benzoate (SLICE; Intervet/ Schering-Plough Animal Health, Roseland, New Jersey) administered in top-dressed, pelleted commercial fish feed was evaluated for control of freshwater Argulus sp. in goldfish Carassius auratus and koi carp, a variant of common carp Cyprinus carpio, in freshwater aquaria at 24–25°C. Sixteen individually housed goldfish were each exposed to 37 Argulus. The number of fish lice attached to each fish at the start of the experiment was not determined; however, the total number of motile fish lice in each aquarium (on fish and in the water) was determined at the start and end of each experiment. Eight goldfish were fed the control diet (0 μg · kg fish biomass?1 · d?1) and eight were fed the medicated diet (50 μg · kg fish biomass?1 · d?1) for seven consecutive days. After treatment, fish louse infestation in controls was 20.5 ± 1.5 (mean ± SE) lice per fish. No Argulus were found on fish in the treated group. In a separate experiment, 10 individually housed koi were each exposed to 128 Argulus. Five koi were fed the control diet and five were fed a low-dose medicated diet (5 μg · kg fish biomass?1 · d?1) for 7 d. After treatment, fish louse infestation among the controls was 14.6 ± 3.8 lice per koi. No Argulus were found on koi in the treated group. Hence, a 7-d regimen of oral emamectin benzoate controlled experimental infestation of Argulus when administered to goldfish at 50 μg · kg fish biomass?1 · d?1 and to koi at 5 μg · kg fish biomass?1 · d?1.

Received March 24, 2010; accepted January 17, 2011  相似文献   
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