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171.
Specimens of Heterobasidion annosum were collected in 104 different stands in 43 regions of Poland. Pure cultures originating from 439 collections were identified in mating tests. Three intersterility groups, P, S and F, of H. annosum were found. Their occurrence in Poland was connected with the natural distribution of the main hosts: Pinus sylvestris, Picea abies and Abies alba, respectively. P was the most common intersterility group of H. annosum in Poland, causing mortality in Scots pine plantations and root rot in older stands. It was also isolated from Betula pendula, P. abies, Larix decidua, Fagus sylvatica and Carpinus betulus. The S group was present in the southern and north‐eastern parts of the country, causing root and butt rot mostly in spruce stands. The F group occurred in the south of Poland, in the mountains, highlands and lowland up to the northern border of the distribution of fir. It was found only on stumps, old dead trees and logs. There was no evidence of damage caused by the F group on A. alba trees. 相似文献
172.
Werner Schuphan 《Journal of pest science》1965,38(8):117-123
Zusammenfassung Es werden die Pflanzenschutzprobleme in ihrer wechselseitigen Verflechtung aus der Sicht der Qualitätsforschung behandelt unter Hinweis auf Möglichkeiten der Erhaltung der Bodenfruchtbarkeit und einer Einschränkung der Anwendung toxischer Pestizide.
Summary Pesticide problems are dealt with in relation and from the standpoint of quality investigations in food plants. Attention is paid to conserve soil fertility by methods of balanced soil management and by a wise restriction on the use of toxic pesticides.相似文献
173.
Hlinak A Mühle RU Werner O Globig A Starick E Schirrmeier H Hoffmann B Engelhardt A Hübner D Conraths FJ Wallschläger D Kruckenberg H Müller T 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(3):105-110
Wild birds are considered a potential reservoir or a carrier of viral diseases and may therefore play a role in the epidemiology of economically important or zoonotic diseases. In 2001 and 2002, a survey with special emphasis on virus isolation in migrating waders and some other birds were conducted. In one of the most important inland resting sites for migratory waterfowl, tracheal and cloacal swabs were collected from 465 waders representing 19 different species, and 165 other birds that were not captured on purpose. A total of 42 avian viruses were isolated, 34 of these were identified as paramyxoviruses (PMVs). The majority of isolates came from waders and wild ducks, and were characterized as PMV-1. In contrast, PMV-4 was found in wild ducks only, PMV-6 was mainly detected in wader species. Four avian influenza viruses (AIVs), belonging to H4 and H3 haemagglutinin subtype, were isolated from wild duck species. Furthermore, four reo-like viruses were isolated from one particular wader species for the first time. The majority of virus positive birds were <1 year old and did not show any clinical symptoms. There was no evidence for the presence of West Nile virus in these birds. These results confirm that the restricted resting sites in Western Europe must be considered as important locations for the intra- and interspecies transmission of avian viruses. 相似文献
174.
Ruoff K Luginbühl W Künzli R Bogdanov S Bosset JO von der Ohe K von der Ohe W Amado R 《Journal of agricultural and food chemistry》2006,54(18):6858-6866
Front-face fluorescence spectroscopy, directly applied on honey samples, was used for the authentication of 11 unifloral and polyfloral honey types (n = 371 samples) previously classified using traditional methods such as chemical, pollen, and sensory analysis. Excitation spectra (220-400 nm) were recorded with the emission measured at 420 nm. In addition, emission spectra were recorded between 290 and 500 nm (excitation at 270 nm) as well as between 330 and 550 nm (excitation at 310 nm). A total of four different spectral data sets were considered for data analysis. Chemometric evaluation of the spectra included principal component analysis and linear discriminant analysis; the error rates of the discriminant models were calculated by using Bayes' theorem. They ranged from <0.1% (polyfloral and chestnut honeys) to 9.9% (fir honeydew honey) by using single spectral data sets and from <0.1% (metcalfa honeydew, polyfloral, and chestnut honeys) to 7.5% (lime honey) by combining two data sets. This study indicates that front-face fluorescence spectroscopy is a promising technique for the authentication of the botanical origin of honey and may also be useful for the determination of the geographical origin within the same unifloral honey type. 相似文献
175.
Red deer (Cervus elaphus) were introduced in southern Latin America about a century ago and characteristics of the invasion raise concerns over their epidemiological role for various diseases. We report on the possible occurrence of Taenia ovis krabbei established in a sylvatic cycle in Patagonia. Hook characters, size, appearance, and location of a cysticercus from a wild red deer are consistent with Taenia ovis ovis or T. o. krabbei. Although it is not possible to differentiate between T. o. ovis and T. o. krabbei on morphological grounds with certainty, several biological characteristics indicate the cysticercus may belong to T. o. krabbei. Red deer have been reported to be refractory to T. o. ovis infection whereas other potential intermediate hosts like cattle, goats, pigs and sheep have been shown to be refractory to T. o. krabbei. Other native ungulates sympatric with red deer in Patagonia include Lama guanicoe and the endangered huemul deer (Hippocamelus bisulcus). Possible or known definitive hosts include native felids like Puma concolor, Felis colocolo, F. guigna and canids like Dusicyon griseus, D. culpaeus, and domestic dogs. 相似文献
176.
Matthias Schr?ter Werner H?rdtle Goddert von Oheimb 《European Journal of Forest Research》2012,131(3):787-798
Competition for canopy space is a process of major importance in forest dynamics. Although virgin and old-growth European
beech (Fagus sylvatica L.) forests in Europe have been studied for many years, there are to date no studies of individual-tree crown plasticity
and the way this is influenced by local neighborhood interactions in these forests. In this study, we analyzed crown plasticity
and local neighborhood interactions of individual trees in the upper canopy of the old-growth beech forests of Serrahn, northeast
Germany. In a 2.8-ha sample plot, we measured crown radii of all upper canopy trees and analyzed the direction and extent
of crown asymmetry. Size, relative position, and distance of neighboring trees were used to construct vectors of neighborhood
asymmetry within different distances from target trees. The crowns of beech trees showed strong morphological plasticity.
Mean absolute and relative displacement of crown centers from the stem base were 1.95 m and 0.37, respectively. Circular–circular
rank correlation coefficients between the direction of crown displacement and the direction of neighborhood pressure showed
that trees strongly positioned their crowns away from local neighbors. Highest correlation coefficients were obtained when
basal area and relative position of neighboring trees within a radial distance of 12 m were considered. Clark and Evans index
and Ripley’s K-function showed that crowns were more regularly distributed than stems. Projected canopy cover was about 10% higher than
canopy cover with simulated circular crowns. We conclude that the crowns of older beech trees have a high ability to plastically
respond to changes in the local canopy conditions, enabling very effective exploitation of canopy space. 相似文献
177.
Megan I. Gerber Ann M. Swinker W. Burton Staniar Jacob R. Werner Edward A. Jedrzejewski Ann L. Macrina 《Journal of Equine Veterinary Science》2012
The objectives of this study were to characterize the inflammatory response after microchip insertion, evaluate pain response and swelling at the microchip insertion site, and measure migration of the microchips. Eighteen mature Quarter Horse mares were separated by expected parturition dates and then assigned randomly to treatment groups. The microchip group (n = 7) had microchips inserted using a sterile needle and syringe; the sham group (n = 7) had a needle inserted but no microchip; and the control group (n = 4) had no insertion. The inflammatory response was measured over a 2-week period by measuring dermal temperature, response to pressure, and swelling at the insertion site and plasma serum amyloid A (SAA). For the migration component of the study, radiographs of the seven microchipped horses were taken over 6 months after insertion. These radiographs allowed measurement between a select vertebral point and the microchip. The microchip and sham insertion did not cause a detectable increase in temperature. Algometer readings, used to quantify pressure necessary to induce a pain threshold response, indicated that microchip insertion area was more sensitive than sham insertion at 2 hours, day 1, and day 3 post insertion. Visible swelling began 2 hours postinsertion and resolved by day 3. SAA concentrations were affected by day following insertion, but not by treatment group. Increases in SAA concentration could not be matched with local insertion reactions. Migration was not detected in any of the horses during the 6 months within a 0.7-cm margin of error. 相似文献
178.
Three eight-week-old Golden Retriever puppy littermates were evaluated because of left basilar systolic murmurs and were diagnosed with primary infundibular stenosis. Pedigree analysis in this line was also performed to identify a mode of inheritance. All dogs were asymptomatic at the time of diagnosis; two of the three had congenital lesions in addition to primary infundibular stenosis. Two additional affected dogs were identified in the line, and pedigree analysis suggested an autosomal recessive mode of inheritance. Another, unrelated golden retriever was also identified with isolated infundibular stenosis in the record database. Primary infundibular stenosis should be considered in the differential diagnoses for golden retriever dogs with a left basilar systolic murmur, and is often associated with complex congenital cardiac disease. Primary infundibular stenosis may worsen in severity with time, and in this line of dogs an autosomal recessive pattern of inheritance is likely. 相似文献
179.
180.
MJ Lancaster JS Nimmo C Lenghaus IJ Gill RD Crawford RT Badman JL Samuel CJ Werner C Button N Kvalheim 《Australian veterinary journal》2009,87(12):476-479
Objective To document an ovine disease attributed to the consumption of Lythrum hyssopifolia (lesser loosestrife). Procedures Historical and histological review of field and experimental cases. Results 1–20% mortality occurred in sheep flocks grazing paddocks where L. hyssopifolia was the predominant green vegetation. Well‐documented disease outbreaks occurred in summer on nine farms across Victoria between 1974 and 2002. Liver damage occurred in all nine outbreaks, with kidney damage in at least eight. Hepatocyte necrosis was usually zonal to midzonal (zone 2) in the liver samples from four farms and periacinar (zone 3) in those from three farms, but some livers showed only single‐cell necrosis. Multinucleate hepatocytes near necrotic areas were a feature in six cases. Proximal tubular epithelium appeared to be the primary renal target and brown granules were often present in renal tubules. Biochemical and histological evidence of liver and kidney damage was obtained from two sheep experimentally pen‐fed harvested L. hyssopifolia. Conclusion Chemicals in L. hyssopifolia are toxic to ovine hepatocytes and renal tubular epithelial cells. 相似文献