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51.
Anne-Kathrin Schink Kristina Kadlec Tomasz Hauschild Geovana Brenner Michael Julia C. Dörner Carolin Ludwig Christiane Werckenthin Hans-Robert Hehnen Bernd Stephan Stefan Schwarz 《Veterinary microbiology》2013
In this study, 908 bacterial pathogens from defined infections of dogs and cats were tested for their susceptibility to the novel fluoroquinolone pradofloxacin, which was approved in 2011 for use in cats and dogs. Most of the bacteria tested (Staphylococcus aureus, Staphylococcus pseudintermedius, Escherichia coli, β-haemolytic streptococci, Pasteurella multocida and Bordetella bronchiseptica) exhibited low pradofloxacin MIC90 values of ≤0.25 μg/ml. Solely Proteus spp. and Pseudomonas aeruginosa had higher MIC90 values of ≥4 μg/ml. Only six (3.4%) of 177 S. pseudintermedius and 12 (5.3%) of 227 E. coli isolates showed pradofloxacin MICs of ≥2 μg/ml. Analysis of the quinolone resistance determining regions of the target genes identified double mutations in GyrA that resulted in amino acid exchanges S83L + D87N or S83L + D87Y and single or double mutations in ParC that resulted in amino acid exchanges S80I or S80I + E84G in all 12 E. coli isolates. The six S. pseudintermedius isolates exhibited amino acid exchanges S84L or E88K in GyrA and S80I in GrlA. Comparative analysis of the MICs of pradofloxacin and the MICs determined for enrofloxacin and its main metabolite ciprofloxacin, but also marbofloxacin, orbifloxacin, difloxacin and ibafloxacin was conducted for the target pathogens S. pseudintermedius, E. coli and P. multocida. This comparison confirmed that pradofloxacin MICs were significantly lower than those of the other tested fluoroquinolones. 相似文献
52.
53.
Yohannes Petros Arnulf Merker Habtamu Zeleke 《Genetic Resources and Crop Evolution》2008,55(3):451-458
Genetic relationships and diversity of 45 Guizotia populations each consisting of ten individuals and belonging to five taxa of the genus Guizotia were analyzed using Inter Simple Sequence Repeat (ISSR) markers. Five ISSR primers generated a total of 145 scorable bands
across the 450 individuals used for the study. The percent polymorphic loci for the taxa ranged from 68.2 (G. arborescens) to 88% (G. scabra ssp. schimperi), with G. scabra ssp. scabra, G. zavattarii and G. villosa following G. scabra ssp. schimperi in this order with respect to the abundance of percent polymorphic loci. The Shannon-Weaver diversity indices (H′), for the
five taxa also followed a similar pattern, with G. scabra ssp. schimperi exhibiting the highest H′ (0.7373) and G. arborescens the least (0.5791), while H′ for G. scabra ssp. scabra, G. villosa and G. zavattarii were 0.7313, 0.6620 and 0.6564, respectively. The least genetic distance (0.1188) was observed between G. scabra ssp. schimperi and G.villosa, revealing closer genetic relationships of the two species with each other than with the others, and the highest genetic
distance (0.2740) was observed between G. scabra ssp. schimperi and G. zavattarii. The unweighted pair group method using the arithmetic average clustering of the five taxa using the standard genetic distances
produced two clusters, with G. scabra ssp. schimperi and G. villosa occurring in one cluster and G. scabra ssp. scabra, G. arborescens and G. zavattarii together in the other cluster. The study reveals that G. scabra ssp. schimperi is more closely related to G. villosa than to G. scabra ssp. scabra. 相似文献
54.
Ten released varieties and one hundred and eleven tetraploid (2n = 4x = 28, AABB) wheat accessions collected from different major wheat producing regions, consisting of totally 2904 entries were
characterized for content of yellow pigment, gluten strength, thousand kernel weights, grain yield, percent of yellow berry,
glumes color, awn color, seed color, beak shape and spike density. The objectives were to assess variation with respect to
regions of origin, species and altitudinal classes and to study the interrelationships of the qualitative traits used for
the study. The accessions and/or released varieties showed significant regional variation for all the traits used in the study,
but clinal variation among altitudinal classes and species were significant (P ≤ 0.01) in 6 (60%) and 9 (90%) of the studied traits, respectively. The accessions revealed consistent variation (P ≤ 0.001) within both regions and altitudinal classes for all the traits used in the study. The sedimentation volume was positively
correlated with content of yellow pigment, percent of yellow berry, thousand kernel weights, glumes color, awn color, beak
shape, seed color and grain yield. The contents of yellow pigment was positively correlated with awn color, beak shape and
grain yield, but negatively correlated with seed color and spike density. Generally wide variation was found in the germplasm.
Particularly variation was high for the content of the yellow pigment as well as the gluten strength, which provides opportunities
to be utilized for genetic improvement. 相似文献
55.
Y. Petros A. S. Carlsson S. Stymne H. Zeleke A.‐S. Fält A. Merker 《Plant Breeding》2009,128(6):691-695
Oleic acid content was increased from approximately 5–11% to 80–86% in Guizotia abyssinica (L. f.) Cass. materials from Ethiopia after repeated selection and breeding. Achenes collected from Ethiopia were screened for elevated oleic acid content by half seed technique. The starting materials for breeding were nine plants selected from among 272 seeds analysed and having an average oleic acid content of approximately 21% which is considered to be high compared with the 5–11% reported earlier for niger materials of Ethiopian origin. It was observed that the oleic acid content steadily increased after each round of selection and breeding. The percent oleic acid in the seed oil increased to an average of 35.2% and 53.4% after the first and second round of breeding, respectively and ultimately to over 80% after the third round of breeding. It was also observed that the percent oleic acid in the oil stabilizes and the plants breed true when the oleic acid content in the parental seeds was above 79%. 相似文献
56.
Oligogenic control of resistance to soil‐borne viruses SBCMV and WSSMV in rye (Secale cereale L.)
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Wiltrud Erath Eva Bauer Ute Kastirr Malthe Schmidt Viktor Korzun Brigitta Schmiedchen Peer Wilde Chris‐Carolin Schön 《Plant Breeding》2016,135(5):552-559
Rye production in European growing areas is constrained by the soilborne cereal mosaic virus (SBCMV) and the wheat spindle streak mosaic virus (WSSMV). To date, no European rye cultivars are known to exhibit resistance against these viruses. In this study, we pursued a quantitative trait locus (QTL) mapping strategy to identify genomic regions for resistance to SBCMV and WSSMV in rye. Three populations, each comprising 100 lines segregating for resistance to SBCMV and/or WSSMV, were evaluated for disease response at two years in three locations in Germany where soils are naturally infested with SBCMV and WSSMV. In the combined analysis across environments, one QTL for SBCMV resistance on chromosome 5R explained 31.9% of the phenotypic variation in one of the populations. For WSSMV resistance, one QTL explaining up to 64.0% of the phenotypic variation was detected on chromosome 7R in each of the three populations. On the Triticeae homoeologous group 5, we found evidence for synteny of the major QTL for SBCMV resistance between the wheat and rye genomes. 相似文献
57.
Oliver Pflugh?ft Carolin Merker Andreas von Tiedemann Bernhard C. Sch?fer 《Gesunde Pflanzen》2012,64(1):39-48
Monitoring of the pathogen spectrum in grain peas (Pisum sativum L.) was conducted in Germany between 2005 and 2007. The outcome of this study implies that the infections of pathogens depend on the annual weather condition and the geographic area.Ascochyta pinodes, which infects aerial plant organs, was the pathogen found most frequently (on average 61, 8%). Especially in years with moist weather conditions a more severe spreading of the pathogen could be observed. Similarly, the occurrence ofBotrytis cinerea depends on the weather conditions. In 2007 were optimal conditions for infections and consequentlyB. cinerea was found with a high frequency of about 70%. Regarding diseases on root and stem base, this study clearly shows that infection of less prominent Fusarium species, such asF. redolens andF. avenaceum was significantly higher compared toF. oxysporum andF. solani. 相似文献
58.
Journal of Plant Diseases and Protection - For rapid and sensitive detection of Xanthomonas fragariae, the causal agent of angular leaf spot of strawberry, a nested polymerase chain reaction (Pcr)... 相似文献
59.
Karl-Heinz Hellwald Carolin Zimmermann Heinrich Buchenauer 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(1):95-99
A selection of cucumber mosaic virus (CMV) subgroup I strains originating from Asia and Fny-CMV isolated in USA were studied for their interaction with tomato plants. All strains caused mosaic, fernleaf expression and stunting of tomato plants. Symptom expression was relatively mild after infection with Fny-CMV, T-CMV, Le-CMV and MB-CMV, whereas strains PRC-CMV, NT-CMV and K-CMV caused more severe symptoms. Biologically active clones of NT-CMV RNAs 2 and 3 were generated to construct pseudorecombinant viruses with Fny-CMV to map the symptom determining RNA. The pseudorecombinant FNF-CMV (RNAs 1 and 3 from Fny-CMV, RNA 2 from NT-CMV) showed a similar phenotype on tomatoes to those caused by NT-CMV, whereas FFN-CMV (RNAs 1 and 2 from Fny-CMV, RNA 3 from NT-CMV) induced symptoms comparable to Fny-CMV. The data indicate that CMV RNA 2 of NT-CMV is involved in the induction of severe symptoms in tomato plants. 相似文献
60.
F. Merker 《Journal of pest science》1962,35(12):192-192