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91.
92.
A juvenile cheetah (Acinonyx jubatus) died with rapidly progressive pyrexia, tachypnea, abdominal effusion, and hepatomegaly. Postmortem examination revealed lesions consistent with acute disseminated infection with Toxoplasma gondii. The presence of this organism was confirmed in multiple organs by immunohistochemistry and polymerase chain reaction. To the best of our knowledge, we propose this to be the first reported case of primary acute disseminated toxoplasmosis in a cheetah. 相似文献
93.
Otmar Spring Mark Bachofer Marco Thines Alexandra Riethmüller Markus Göker Franz Oberwinkler 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(3):309-315
Sequence parts of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA were analysed to screen for the intraspecific
variability of a non-coding genomic region in 15 Plasmopara halstedii populations of different pathotype and geographic origin. Samples revealed uniformity in a ca. 790 Bp fragment comprising
of the ITS-1, 5.8S and front parts of the ITS-2. In contrast, clear differences were found in a ca. 810 Bp fragment of the
ITS-2 thus allowing differentiation between populations of pathotype 100, 310 and 330 and a group of populations representing
pathotypes 700, 701, 703, 710 and 730. Samples of pathotypes 700 to730 originated from Slovakia, France, and Germany, but
were uniform in both ITS sequence parts, thus indicating very recent origin of these highly aggressive physiological races.
The potential use of ITS sequences for pathotype differentiation and phylogenetic studies in P. halstedii is discussed. 相似文献
94.
Anne E. Desjardins Mark Busman Michael Muhitch Robert H. Proctor 《Physiological and Molecular Plant Pathology》2007,70(4-6):149-160
Zea mays often is colonized with the fungus Gibberella moniliformis, which produces fumonisin toxins. The role of fumonisins in seedling colonization and blight was studied using complementary genetic analyses of host and pathogen. Only one of two fumonisin B1 (FB1)-insensitive maize backcross lines was more resistant than the FB1-sensitive parent to seedling blight, indicating that the increase in FB1-insensitivity was not associated with an increase in resistance. FB1-producing and nonproducing isogenic fungal strains did not differ in ability to cause seedling blight, but the FB1-producing strain was more effective in systemic colonization of seedlings in reciprocal strain challenge tests. Together, these and previous results indicate that the role of fumonisins depends on complex environmental and genetic contexts in this host–pathogen interaction. 相似文献
95.
Philipp B. Gannibal Sonja S. Klemsdal Mark M. Levitin 《European journal of plant pathology / European Foundation for Plant Pathology》2007,119(2):175-182
Alternaria tenuissima is a common pathogen on a number of plants described in several geographic regions of the world. Genetic variation within
and between Russian Far East, North West and Caucasus populations of A. tenuissima from wheat was examined. In addition, genetic differences between isolates from various hosts were estimated. In total, 101
isolates of A. tenuissima were studied using amplified fragment length polymorphism (AFLP) with four primer combinations. Wright’s fixation index (F
st), gene flow (N
m) and gene diversity (H
s) were calculated. AFLP banding patterns indicated significant genetic distance and at the same time a low level of gene flow
between the Far East and the two other groups of isolates originating from the European part of country. The degree of similarity
between the North West and Caucasus populations was very high, as was the migration rate. Isolates analysed by UPGMA-based
cluster analysis were grouped according to location of origin but irrespective of plant host. Based on the F
st value, the group of isolates originating from wheat and barley were not found to differ significantly from each other. 相似文献
96.
ABSTRACT Unmodified and low water activity (a(w))-tolerant cells of Candida sake CPA-1 applied before harvest were compared for ability to control blue mold of apples ('Golden Delicious') caused by Penicillium expansum under commercial storage conditions. The population dynamics of strain CPA-1 on apples were studied in the orchard and during storage following application of 3 x 10(6) CFU/ml of each treatment 2 days prior to harvest. In the field, the population size of the unmodified treatment remained relatively unchanged, while the population size of the low-a(w)-modified CPA-1 cells increased. During cold storage, the populations in both treatments increased from 10(3) to 10(5) CFU/g of apple after 30 days, and then declined to about 2.5 x 10(4) CFU/g of apple. In laboratory studies, the low-a(w)-tolerant cells provided significantly better disease control as compared with the unmodified cells and reduced the number of infected wounds and lesion size by 75 and 90%, respectively, as compared with the non-treated controls. After 4 months in cold storage, both unmodified and low-a(w)-tolerant cells of C. sake were equally effective against P. expansum on apple (>50% reduction in size of infected wounds). 相似文献
97.
Lia W. Liefting Anna C. Padovan Karen S. Gibb Ross E. Beever Mark T. Andersen Richard D. Newcomb David L. Beck Richard L.S. Forster 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(6):619-623
Sequence comparisons and phylogenetic analysis of the 16S rRNA genes and the 16S/23S spacer regions of the phytoplasmas associated with Australian grapevine yellows, papaya dieback and Phormium yellow leaf diseases revealed minimal nucleotide differences between them resulting in the formation of a monophyletic group. Therefore, along with Australian grapevine yellows, the phytoplasmas associated with Phormium yellow leaf and papaya dieback should also be considered as Candidatus Phytoplasma australiense. 相似文献
98.
Pascucci I Capobianco Dondona A Cammà C Marcacci M Di Domenico M Lelli R Scacchia M Jago M Khaiseb S Hager AL Tjipura-Zaire G Caporale V 《Journal of zoo and wildlife medicine》2011,42(4):634-640
A capture operation to ascertain health status in free-ranging buffaloes from six different areas in the Caprivi Strip in the northeast corner of Namibia was conducted in October 2009. Basic information on the ticks and tick-borne pathogens normally found in wildlife from this area are scarce. The objective of this study was to assess the host status of African buffaloes, Syncerus caffer, for ixodid ticks and two selected tick-borne pathogens in the Caprivi Strip, a key area bordering Angola, Zambia, Botswana, and Zimbabwe. Four different tick species have been identified among the 233 collected specimens, and, of 95 tested buffaloes, 54 (57%) were positive for Theileria parva, whereas only 3 (3%) showed evidence of being infected with Ehrlichia ruminantium. 相似文献
99.
Of the many client groups with interests in irrigation system performance, farmers are probably the least often considered. This paper attempts to explore the meaning of irrigation performance from their perspective, highlighting at the outset basic difference between this perspective and that of system managers. It then reviews several important concepts underlying a consideration of performance in irrigation systems. The paper then proposes and discusses a set of twelve measures of irrigation service judged to be of interest to farmers. These are adequacy, timeliness, equity, tractability, convenience, predictability, temperature, sediment content, salt content, nutrient content, toxics, and pathogens. 相似文献
100.
Sánchez-Patán F Bartolomé B Martín-Alvarez PJ Anderson M Howell A Monagas M 《Journal of agricultural and food chemistry》2012,60(13):3396-3408
Cranberry (Vaccinium macrocarpon) products have been widely recommended in traditional American medicine for the treatment of urinary tract infection (UTI). A total of 19 different commercial cranberry products from American and European markets have been analyzed by different global phenolic methods and by UPLC-DAD-ESI-TQ MS. In addition, in vitro antioxidant capacity and uropathogenic bacterial antiadhesion activity tests have been performed. Results revealed that products found in the market widely differed in their phenolic content and distribution, including products completely devoid of flavan-3-ols to highly purified ones, either in A-type proanthocyanidins (PACs) or in anthocyanins. The product presentation form and polyphenolic profile widely affected the antiadhesion activity, ranging from a negative (nulel) effect to a MIC = 0.5 mg/mL for cranberry powders and a MIC=112 mg/mL for gel capsule samples. Only 4 of 19 products would provide the recommended dose of intake of 36 mg total PACs/day. Of most importance was the fact that this dose would actually provide as low as 0.00 and up to 205 μg/g of procyanidin A2, indicating the lack of product standardization and incongruence between global and individual compound analysis. 相似文献