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151.
Marion Zapater Nathalie Br??da Damien Bonal Sylvia Pardonnet Andr?? Granier 《Annals of Forest Science》2013,70(1):31-39
? Introduction
In the context of global environmental changes, better understanding of tree response to soil drought in young mixed species stands is needed to anticipate forest adaptation and management practices for the future.? Materials and methods
We investigated the functional response of five co-occurring broad-leaved tree species growing in a 15- to 25-year-old mixed stand in northeastern France during the 2006 summer drought. We measured functional traits related to water acquisition (phenology, rooting pattern and vulnerability of xylem to cavitation) and the ecophysiological response (sap flux density, leaf water potential) of these species to soil water shortage.? Results
Our study highlights contrasted drought response strategies among these species and a trade-off between leaf phenology, resistance of xylem to cavitation and root system depth.? Conclusion
At this site, a deep root system seemed to be a key functional trait for the species to cope with drought. Quercus robur and Salix capreae can be characterised as drought-avoidance species as they possess a deep root system and therefore did not strongly experience soil drought. Despite deep rooting capacity, Betula pendula did not really avoid soil drought and strongly regulated transpiration during dry periods. Nevertheless, the earliness of budburst of this species contributes to high annual growth rate. In contrast, Carpinus betulus and Fagus sylvatica both displayed typical characteristics of drought-sensitive species. 相似文献152.
Asman Asman Rosmana Ade Purung Mohd. Hussin bin Amiruddin Andi Amin Nur Sjam Sylvia Dewi Vien Sartika 《植物病害和植物保护杂志》2021,128(1):303-309
Journal of Plant Diseases and Protection - Xylosandrus compactus is one of the significant beetle pests on perennial crops, which has become an increasing problem on cacao productivity and... 相似文献
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: Bulk tank milk samples, collected from 347 herds throughout the Republic of Ireland using a sampling frame based on seven milk-recording organisations, were tested by ELISA for antibodies to Leptospira interrogans serovar hardjo. These herds, which had not been vaccinated against leptospirosis within the previous five years, were categorised according to their province, milk-recording organisation and size. Two-hundred-and-seventy-three herds (79%) had a positive ELISA titre. Both the probability of a herd being seropositive and the antibody level in the herd milk sample were affected by the province (P < 0.05 and P < 0.01, respectively) and the herd size category (P < 0.05 and P < 0.01, respectively). Larger herds were significantly more likely to have positive reactions and higher mean concentrations of antibody. It was concluded that a high proportion of unvaccinated Irish dairy herds have been exposed to infection with Leptospira hardjo. 相似文献
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Palacio J León-Artozqui M Pastor-Villalba E Carrera-Martín F García-Belenguer S 《Journal of Feline Medicine and Surgery》2007,9(3):188-195
Feline aggression towards people has a smaller incidence than canine aggression, but also represents an important public health problem. The aim of this work was to analyse feline aggression reported towards people, to estimate its incidence and to assess the risk factors involved. The information was obtained from the Public Health Centres in the Valencian Region (Spain). A total of 936 acts of feline aggression were analysed. Cats inflicted 8% of all animal bites reported. The annual average was 6.36 feline aggression incidents per 100,000 people. Most aggressive incidents occurred during the summer months. Children (0-14 years old) and women were more likely to be bitten. Wounds were mainly punctures, single, and mild, and were located mostly on the hands. In children, the head and neck areas were affected much more than in adults. The cats involved in incidents were mostly Siamese, female and owned; these cats mainly attacked their owners. Most occurrences were a defensive response by the cat. 相似文献
159.
Prysliak T van der Merwe J Lawman Z Wilson D Townsend H van Drunen Littel-van den Hurk S Perez-Casal J 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(11):1195-1202
To determine if previous exposure to bovine viral diarrhea virus (BVDV) and bovine herpes virus 1 (BHV-1) type 2 affects the onset of disease caused by Mycoplasma bovis, 6- to 8-month-old beef calves were exposed to BVDV or BHV-1 4 d prior to challenge with a suspension of 3 clinical isolates of M. bovis. Animals were observed for clinical signs of disease and at necropsy, percent abnormal lung tissue and presence of M. bovis were determined. Most animals pre-exposed to BHV-1 type 2 but not BVDV developed M. bovis-related respiratory illness. In a second trial, we determined that a 100-fold reduction in the number of M. bovis bacteria administered to BHV-1 exposed animals reduced the percentage of abnormal lung tissue but not the severity of clinical signs. We conclude that previous exposure to BHV-1 but not BVDV type 2 was a necessary cause of M. bovis-related respiratory diseases in our disease model. 相似文献
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Jay Ram Lamichhane Birol Akbas Claus Bo Andreasen Wilma Arendse Sylvia Bluemel Silke Dachbrodt-Saaydeh 《国际虫害防治杂志》2018,64(4):352-358
Recent years have seen an increasing effort towards the development and adoption of sustainable crop protection strategies, especially in the EU. Several policy frameworks have been put in place including the EU framework Directive (128/EC/2009) on the sustainable use of pesticides. Consequently, all EU Member States developed National Action Plans to ensure the implementation of the general principles of Integrated Pest Management (IPM) by all professional pesticide users starting from January 1, 2014. On the other hand, there are also difficulties related to the adoption of IPM in Europe and worldwide which seek for a better understanding of factors hindering IPM uptake. This paper presents the potential role that each actor of the food chain may have – called here stakeholders – to ensure a higher level IPM adoption in Europe. The information reported here is a summary based on several discussions held within a three-year European Research Area Network project on Coordinated Integrated Pest Management (ERA-Net C-IPM; http://c-ipm.org/). 相似文献