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991.
Thomas Miedaner Peter Risser Sophie Paillard Thorsten Schnurbusch Beat Keller Lorenz Hartl Josef Holzapfel Viktor Korzun Erhard Ebmeyer H. Friedrich Utz 《Molecular breeding : new strategies in plant improvement》2012,29(3):731-742
Septoria tritici blotch (STB), caused by S. tritici, Stagonospora glume blotch (SGB), caused by S. nodorum, and Fusarium head blight (FHB), caused by F. graminearum and F. culmorum, are the most important diseases of wheat (Triticum aestivum L.) in temperate growing areas. The main goals of this study were to detect (1) new quantitative trait loci (QTL) for STB
resistance in two adapted European biparental populations (Arina/Forno, History/Rubens) and (2) QTL regions for broad-spectrum
resistance (BSR) to the above-mentioned diseases during the adult-plant stage in the field. The three resistances were phenotyped
across 4–7 field environments and phenotypic data revealed significant (P < 0.01) genotypic differentiation in all cases. Entry-mean heritabilities (h2) ranged from 0.73 to 0.93. For STB resistance, correlations between disease ratings and heading date were significant (P < 0.01), but moderate (r = −0.23 to −0.30) in both populations. Correlations between STB and plant height were higher in Arina/Forno (r = −0.45) and History/Rubens (r = −0.55), the latter population segregating at the Rht-D1 locus. During the initial QTL analysis, 5 QTL were detected for STB resistance in each of the populations, amounting to an
explained genotypic variance of 45–63%, thus, showing the same ranges as FHB and SGB resistances in Arina/Forno and FHB resistance
in History/Rubens. In total, 7 BSR QTL were found in the meta-analysis with the raw data, including the QTL on chromosome
4D at the Rht-D1 locus. A BSR QTL for all three diseases was not found but several BSR QTL for combinations with two diseases were detected.
Combining the BSR QTL detected in the present breeding material by applying marker-assisted selection seems a promising approach. 相似文献
992.
New model of tertiary structure of plant 5S rRNA is confirmed by digestions with alpha-sarcin 总被引:1,自引:0,他引:1
M Z Barciszewska S Lorenz A Joachimiak N Ulbrich V A Erdmann J Barciszewski 《FEBS letters》1990,269(1):83-85
The cytotoxin alpha-sarcin was employed to test the model of secondary and tertiary structures of plant 5S rRNAs, which we recently proposed [(1990) Int. J. Biol. Macromol. (in press)]. alpha-Sarcin is a novel ribonuclease that hydrolyzes phosphodiester bonds adjacent to purines in nucleic acids. The digestion pattern obtained for lupin and wheat germ 5S rRNAs strongly suggests the existence of tertiary interactions between residues C34, C35, C36, A37 and G85, G86, G87, U88 as previously proposed. The results on the secondary structure of plant 5S rRNA are in line with a previously proposed model. 相似文献
993.
A number of proteins, termed chaperonins, have been identified as part of the mechanism of folding other proteins into their biologically active forms. The role of chaperonins appears to be twofold--to prevent illegitimate interactions with other proteins and to facilitate folding, possibly through an energy-dependent, catalytic function. Controlled overexpression of chaperonins may be of therapeutic value in manipulating human immune response and rescuing certain inherited human mutations. 相似文献
994.
Background
Microarrays offer great potential as a platform for molecular diagnostics, testing clinical samples for the presence of numerous biomarkers in highly multiplexed assays. In this study applied to infectious diseases, data from a microarray designed for molecular serotyping of Streptococcus pneumoniae was used, identifying the presence of any one of 91 known pneumococcal serotypes from DNA extracts. This microarray incorporated oligonucleotide probes for all known capsular polysaccharide synthesis genes and required a statistical analysis of the microarray intensity data to determine which serotype, or combination of serotypes, were present within a sample based on the combination of genes detected. 相似文献995.
Peng Wang Ellen L. Marsh Greg Kruger Aaron Lorenz Daniel P. Schachtman 《Environmental microbiology》2020,22(3):889-904
Root-associated microbial communities are important for maintaining agricultural productivity. However, belowground microbial community response to drought in temperate maize agroecosystems, as well as how these responses to water-stress are shaped by host genotype are poorly understood. Ten maize hybrids (six newer and four older) were grown in a replicated field trial. The endosphere, rhizosphere and soil bacterial and archaeal communities were sampled and analyzed using 16S rRNA gene amplicon sequencing. Sampling was done at two developmental stages in a water-limited environment with and without supplemental irrigation. Significant shifts in microbial community composition (β-diversity) were measured between two sampling times during the season, in well-watered and water-stressed conditions and in newer and older generation maize hybrids. The microbial community diversity within samples (α-diversity) was not affected by drought stress or host factors. The phyla Actinobacteria and Firmicutes were more abundant in the rhizosphere of newer hybrids under water stress. These results highlight the importance of temporal variation, environmental stress and plant genetics as influenced by breeding history in shaping the composition of root associated microbial communities. These insights may provide new approaches to the improvement of crop stress tolerance through optimizing microbial communities. 相似文献
996.
Alba Alfonso‐Garcia Julien Bec Shamira Sridharan Weaver Brad Hartl Jakob Unger Matthew Bobinski Mirna Lechpammer Fady Girgis James Boggan Laura Marcu 《Journal of biophotonics》2020,13(1)
Current clinical brain imaging techniques used for surgical planning of tumor resection lack intraoperative and real‐time feedback; hence surgeons ultimately rely on subjective evaluation to identify tumor areas and margins. We report a fluorescence lifetime imaging (FLIm) instrument (excitation: 355 nm; emission spectral bands: 390/40 nm, 470/28 nm, 542/50 nm and 629/53 nm) that integrates with surgical microscopes to provide real‐time intraoperative augmentation of the surgical field of view with fluorescent derived parameters encoding diagnostic information. We show the functionality and safety features of this instrument during neurosurgical procedures in patients undergoing craniotomy for the resection of brain tumors and/or tissue with radiation damage. We demonstrate in three case studies the ability of this instrument to resolve distinct tissue types and pathology including cortex, white matter, tumor and radiation‐induced necrosis. In particular, two patients with effects of radiation‐induced necrosis exhibited longer fluorescence lifetimes and increased optical redox ratio on the necrotic tissue with respect to non‐affected cortex, and an oligodendroglioma resected from a third patient reported shorter fluorescence lifetime and a decrease in optical redox ratio than the surrounding white matter. These results encourage the use of FLIm as a label‐free and non‐invasive intraoperative tool for neurosurgical guidance. 相似文献
997.
With the Psychological Capital Questionnaire (PCQ) being the standard measure to assess psychological capital (PsyCap) in the context of organizations, this paper aims to broaden this domain-specific approach by introducing a measure with universal claim. Two studies were conducted to create and validate a German self-report scale (CPC-12) measuring PsyCap. We performed confirmatory factor analyses and correlations with other positive psychological constructs on the data of two German samples (N1 = 321; N2 = 202). The twelve-item CPC-12 exhibits the anticipated factorial structure with a very good model fit and associations to other constructs concur with previous findings with other measures of PsyCap. 相似文献
998.
Lorenz Gygax 《Ethology : formerly Zeitschrift fur Tierpsychologie》1995,101(1):10-24
During an observational study of captive longtailed macaques (Macaca fascicularis), the ability to hide was analysed within the social context of mating. Low- and middle-ranking males and their female partners chose places for mating where they were partly or entirely concealed more often than easily visible places. These places were not the preferred places of either sex in general, although it was also observed that lower-ranking animals of both sexes lead a more inconspicuous life than high-ranking animals. The probable mechanisms of this phenomenon are discussed: trial-and-error learning or a simple rule of thumb seem to be the appropriate explanations since the choice between different structures of hiding places is not as sharply defined as would be expected if ‘perspective taking’ were the mechanism. 相似文献
999.
1000.
Micha?l Beaulieu Ines Bischofberger Isabel Lorenz Lucie Scheelen Klaus Fischer 《Biology letters》2016,12(2)
The significance of dietary antioxidants may be limited by the ability of animals to exploit them. However, past studies have focused on the effects of dietary antioxidants after ‘antioxidant forced-feeding’, and have overlooked spontaneous antioxidant intake. Here, we found that reproducing female Bicyclus anynana butterflies had higher antioxidant defences and enhanced fecundity when forced to consume antioxidants (polyphenols). Interestingly, these positive effects were not constant across the oviposition period. When given the choice between food resources with and without antioxidants, reproducing butterflies did not target antioxidants when they could have benefited the most from them. Moreover, they did not consume more antioxidants than non-reproducing butterflies. These results emphasize that, despite potential positive effects of dietary antioxidants, the ability of animals to exploit them is likely to restrict their ecological significance. 相似文献