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51.
52.
Successful selection of interspecific hybrid progenies with superior ability to regenerate shoots from apical meristems was
performed in sunflower which now allows for the development of lines for improved biotechnological applications. Early generations
of interspecific hybrids originating from crosses between the two H. annuus CMS lines ‘HA89’ and ‘Baso’, and 9 wild species were screened for their ability to regenerate in vitro. Evaluation of 36 progenies allowed to identify seven progenies from crosses involving H. mollis, H. giganteus, H. strumosus, and H. decapetalus which showed a significantly higher regeneration potential than the commercial hybrid ‘Albena’ regarding the number of shoots
per explant. Among these progenies, 47.2 to 62.4% of explants produced shoots with an average of 2.3 to 3.5 shoots per cultured
explant. Regeneration in vitro was significantly determined by the genotype. More than half of the investigated interspecific hybrids performed better than
the inbred ‘HA89’ demonstrating that the high regeneration potential available in the wild species can be efficiently transferred
to cultivated sunflower. The seven progenies with high regeneration potential in vitro were characterised by agronomic performance in the field. Two of the interspecific hybrids derived from H. strumosus and H. decapetalus not only showed a superior regeneration potential but also proved to be competitive to commercial hybrids with regard to
important agronomic traits, e.g. fat content and TGW.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
53.
R. C. Recouso R. C. Stocco dos Santos R. Freitas R. C. Santos A. C. de Freitas O. Brunner W. Beçak C. J. Lindsey 《Veterinary and comparative oncology》2003,1(1):22-29
Ingestion of bracken fern (Pteridium aquilinum v. arachnoideum) is associated with digestive tract cancer in different regions of Japan, Venezuela and Brazil. In view of reports that dietary bracken fern causes chromosomal instability in cattle, the clastogenic effect of bracken fern was investigated, in a preliminary study, in peripheral lymphocytes obtained from habitual consumers and a control group of non‐consumers, which were carefully investigated about cancer history or family cancer history, negative in both cases, using protocols comparable to those previously described in studies in cattle raised on bracken pastures. Cytogenetic analysis showed significant increased levels of chromosomal abnormalities, such as chromatid breaks, in cultured peripheral lymphocytes of the consumer group. There was no correlation with subjects, gender, smoking habits or alcohol consumption, and the only correlation was with prolonged exposure to dietary bracken. 相似文献
54.
Renate Bockholt 《Archives of Agronomy and Soil Science》2013,59(3-4):183-199
In die Auswertung sind 34 Pflanzenarten (Gräser, Kräuter, Leguminosen) einbezogen worden. Es werden Variationsbreiten, Trends und Mittelwerte von Parametern des Futterwertes und der Siliereignung in Diagrammen dargestellt. Die Diagramme enthalten den Rohproteingehalt, die Energiedichte, den Zuckergehalt, die Pufferkapazität, den Z/PK‐Quotienten und den Nitratgehalt. Auf Grund der starken Differenzierung der Arten ist eine uniforme Bewertung der Pflanzen im Hinblick auf die untersuchten Parameter nicht zulässig. Die Prognose von Futterwert und Siliereignung über das Arteninventar von Teilflächen erscheint gerechtfertigt. Im Mittel der Pflanzen sind eher Defizite in Bezug auf die Energiedichte als in Bezug auf die Silagequalität zu erwarten. Für die Verwendung der Ergebnisse werden Tabellen angeboten, die hier nicht ausgedruckt worden sind. Diese Tabellen können von der Verfasserin angefordert werden. 相似文献
55.
Renate Koenig 《Journal of pest science》1970,43(6):81-83
Zusammenfassung Verschiedene Anwendungsmöglichkeiten der Serologie in der pflanzlichen Virusforschung werden diskutiert. Von besonderer Bedeutung sind Antikörper für die Diagnose von Viruskrankheiten und für Verwandtschaftsuntersuchungen. Markierte Antikörper dienen als Nachweisreagentien in histologischen und zytologischen Untersuchungen. Analysen von Oberflächenstrukturen mit Hilfe von Antikörpern wurden bei Pflanzenviren bisher nur selten durchgeführt.
Summary Several applications of serology in plant virus research are discussed. Antibodies are especially important for diagnostic purposes and for investigations on relationships. Labelled antibodies are used as specific tracers in histological and cytological studies. Up to now, only a few analyses of surface structures have been performed in plant virus work by means of antibodies.
Résumé Pluseurs modes d'application de la sérologie dans la sphère de la virologie végétale sont discutés. Les anticorps sont d'importance spéciale pour le diagnostic des viroses et pour l'exploration des parentées. On se serve des anticorps marqués comme réactifs histologiques et cytologiques. Jusqu'aujourd'hui des analyses de structures superficielles ont été faites rarement chez les vires végétaux.相似文献
56.
Urban forest management needs information about the amount andkinds of recreation use, in particular about emerging recreationalactivities such as Nordic walking and winter bicycling. Between2003 and 2004, year-round use levels of recreational activitieswere investigated in a forest in Vienna using permanent time-lapsevideo recording and counts by human observers on sampling days.The amount of use, yearly, weekly and daily use patterns, aswell as the group size of the traditional activity groups werecompared with Nordic walking and winter bicycling to characterizethese activities and to better understand recreation use. Forall activity groups, the rates of participation varied significantlyacross most of the time dimensions, and the relationships betweenthe time of day and rates of participation were different forindividuals and groups. Nordic walkers displayed a temporaluse pattern similar to that of jogging with workday eveningand weekend morning use peaks, while winter bicycling was similarto bicycling activities with afternoon use peaks during snowyperiods. Nordic walking and winter bicycling activities addedto the multi-use character of the heavily used forest, but seemednot to increase the potential for user conflicts because ofthe current low participation rates and the Nordic walking group'savoidance of times of heavy use. 相似文献
57.
Tuskan GA Difazio S Jansson S Bohlmann J Grigoriev I Hellsten U Putnam N Ralph S Rombauts S Salamov A Schein J Sterck L Aerts A Bhalerao RR Bhalerao RP Blaudez D Boerjan W Brun A Brunner A Busov V Campbell M Carlson J Chalot M Chapman J Chen GL Cooper D Coutinho PM Couturier J Covert S Cronk Q Cunningham R Davis J Degroeve S Déjardin A Depamphilis C Detter J Dirks B Dubchak I Duplessis S Ehlting J Ellis B Gendler K Goodstein D Gribskov M Grimwood J Groover A Gunter L Hamberger B Heinze B 《Science (New York, N.Y.)》2006,313(5793):1596-1604
We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport. 相似文献
58.
Papassotiropoulos A Stephan DA Huentelman MJ Hoerndli FJ Craig DW Pearson JV Huynh KD Brunner F Corneveaux J Osborne D Wollmer MA Aerni A Coluccia D Hänggi J Mondadori CR Buchmann A Reiman EM Caselli RJ Henke K de Quervain DJ 《Science (New York, N.Y.)》2006,314(5798):475-478
Human memory is a polygenic trait. We performed a genome-wide screen to identify memory-related gene variants. A genomic locus encoding the brain protein KIBRA was significantly associated with memory performance in three independent, cognitively normal cohorts from Switzerland and the United States. Gene expression studies showed that KIBRA was expressed in memory-related brain structures. Functional magnetic resonance imaging detected KIBRA allele-dependent differences in hippocampal activations during memory retrieval. Evidence from these experiments suggests a role for KIBRA in human memory. 相似文献
59.
Nathues H Spergser J Rosengarten R Kreienbrock L Grosse Beilage E 《Veterinary journal (London, England : 1997)》2012,193(2):443-447
The diagnosis of enzootic pneumonia at the herd level should be based on a combination of different methods. Currently, clinical examination is usually considered to be a low value method, particularly compared to the direct detection of Mycoplasma hyopneumoniae in lung lesions by PCR. The present study compared the value of accurate clinical examination (including the quantitation of coughing), PCR on bronchoalveolar lavage fluid, and serological testing of blood samples for the purpose of diagnosing enzootic pneumonia. The coughing index (average % of pigs coughing per minute of observation) was determined in fattening pigs from 59 herds, and ranged from 0% to 6.7% with a median of 2.4%. Five hundred and ninety bronchiolar lavage samples and 1179 serum samples were taken from pigs in those 59 herds and tested for M. hyopneumoniae specific DNA and antibodies, respectively. In herds where ?50% of lavage fluids were PCR positive, the likelihood of a higher coughing index was increased by 76% (OR: 1.76; 95% CI: 1.14-2.72) compared to herds with <50% of positive samples. For antibodies (determined by ELISA) a seroprevalence of ?50% increased the likelihood of a high coughing index by 50% (OR: 1.50; 95% CI: 1.03-2.20). In 78.1% of all herds with a seroprevalence of ?50% against M. hyopneumoniae, the PCR-prevalence and the coughing index were above the median (50% and 2.4%, respectively). It was concluded that in fattening pigs a quantitative assessment of the onset of coughing - typically dry and non-productive - improves the diagnosis of enzootic pneumonia and can occasionally substitute for the detection of M. hyopneumoniae by PCR. 相似文献
60.
Pfeifer RM 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(12):993-995
A 4-month-old, female terrier-poodle cross was presented with a chronic history of dysphagia. Fluoroscopic swallowing studies localized the problem to the upper esophageal sphincter. A diagnosis of cricopharyngeal achalasia was made. After cricopharyngeal and thyropharyngeal myectomy, the dog was able to eat soft food without difficulty. 相似文献