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111.
Christiane Kosellek Klaus Pillen James C. Nelson W. Eberhard Weber Bernhard Saal 《Euphytica》2013,194(2):161-176
Breeding for field resistance to Septoria tritici blotch (STB), caused by Mycosphaerella graminicola (anamorph: Septoria tritici), is the most suitable strategy for controlling this important disease of wheat. Although many Stb genes for resistance to single pathogen isolates have been identified in wheat, knowledge of their efficiency against natural fungal populations is lacking. In a quantitative-trait-locus (QTL) mapping approach in six environments and four locations, field resistance to STB was studied in a doubled-haploid population derived from a cross between the field-resistant cultivar Solitär and the susceptible cultivar Mazurka. After plant height as a disease escape trait was accounted for, five QTL with effects on STB response on chromosomes 5A, 6D and 7D explained 20 % of the genotypic variance; QTL × environment interactions were minor. Field resistance was conferred exclusively by alleles from Solitär, which was previously shown to carry the isolate-specific genes Stb6 and Stb11 as well as minor QTL detected with seven fungal isolates. Surprisingly, neither the Stb6 nor Stb11 isolate-specific genes nor minor QTL previously detected in Solitär were found to be involved in its field resistance. The study suggests that resistance breeding for STB should not rest solely on the deployment of Stb genes. Field tests are indispensable to show their efficacy and durability and to identify genes conferring partial field resistance to STB. 相似文献
112.
Equine recurrent uveitis (ERU) is a serious eye disease and the most common cause of blindness in horses. Until now, the cause of ERU is not fully understood. Persistent infections of pathogenic leptospires have been discussed. Chronic recurrent remitting episodes of inflammations and the positive therapeutic effects of corticosteroids have led to the hypothesis that ERU is an autoimmune disorder. The reason for a dysregulated autoimmune response may be linked to genetic factors. ERU shows similarities to human autoimmune uveitis with a genetic background. An association of the equine leukocyte antigen serological haplotype A9 with ERU in warmblood horses indicated that major histocompatibility complex I (MHCI) influences the development of ERU. The different types of human autoimmune and genetic uveitis, like Behçet's disease, systemic sarcoidosis, Vogt-Koyanagi-Harada syndrome, birdshot retinochoroidopathy, sympathetic ophthalmia, and acute recurrent anterior uveitis, had been associated with the human leukocyte antigen complex and genetic variants of the MHC. Furthermore non-MHC genes with a possible role in autoimmunity may also play a role in ERU-affected horses. The genes presented herein may be of interest for genome-wide association analyses of ERU-affected horses. 相似文献
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OBJECTIVES: The aim of this retrospective study was to summarize the most frequent clinical signs, ultrasonographic, and histological findings accompanying scleral rupture as a result of blunt trauma in dogs, cats, and horses. ANIMALS STUDIED AND PROCEDURES: Thirty small animals and three horses diagnosed with scleral rupture resulting from blunt trauma. B-mode ultrasonography was performed on 20 animals. Histopathology was carried out on 18 enucleated globes. RESULTS: In small animals, 80% presented hyphema, 60% subconjunctival hemorrhage, and 53% eyelid and conjunctival swelling. In horses, 100% presented eyelid and conjunctival swelling, 67% hyphema, subconjunctival hemorrhage, and collapsed anterior chamber. Ultrasonographic findings were an area with ill-defined scleral margins (90%), echoic/hyperechoic contents in the anterior and posterior chamber (55%) and in the vitreous (80%). In small animals, scleral rupture location noted on gross examination was: at the posterior pole (4), close to the optic nerve (3), near the limbus (2), and in the dorsal aspect of the globe (1). In horses, the lesion was located at the limbus (3). In small animals, histopathology showed presence of hemorrhage in the anterior, posterior chamber, and vitreous (94%), retinal detachment (94%), choroidal edema and hemorrhages (88%), and choroidal detachment as a result of suprachoroidal hemorrhage (88%). The same lesions were found in the globes of two horses. In small animals, rupture location noted on histopathology was: at the posterior pole (8), close to the optic nerve (4), near the limbus (1), near the ciliary body (1). CONCLUSIONS: The most frequent clinical signs observed were hyphema, subconjunctival hemorrhage, and eyelid and conjunctival swelling. Ultrasonographic findings suggestive for scleral rupture were ill-defined scleral borders and/or echoic/hyperechoic material in the cavities of the globe. On histopathology, lesions severely altering the anatomy of the eye structures were: hemorrhage into the chambers of the globe, subretinal and suprachoroidal hemorrhage leading to retinal and choroidal detachment, respectively. In small animals, the most frequent locations for scleral rupture were the posterior pole and close to the optic nerve, whereas in horses it was the limbus. 相似文献
115.
Daniel Goitom Asfaha Christophe R. Quétel Freddy Thomas Micha Horacek Bernhard Wimmer Gerhard Heiss Christian Dekant Peter Deters-Itzelsberger Stefan Hoelzl Susanne Rummel Christophe Brach-Papa Marleen Van Bocxstaele Eric Jamin Malcolm Baxter Katharina Heinrich Simon Kelly Daniela Bertoldi Luana Bontempo Federica Camin Roberto Larcher Matteo Perini Andreas Rossmann Antje Schellenberg Claus Schlicht Heinz Froeschl Jurian Hoogewerff Henriette Ueckermann 《Journal of Cereal Science》2011
The aim of this work (from the FP6 project TRACE) was to develop methods based on the use of geochemical markers for the authentication of the geographical origin of cereal samples in Europe (cf. EC regulations 2081/92 and 1898/06). For the first time, the potential usefulness of combining n(87Sr)/n(86Sr) and δ13C, δ15N, δ18O and δ34S isotopic signatures, alone or with key element concentrations ([Na], [K], [Ca], [Cu] and [Rb], progressively identified out of 31 sets of results), was investigated through multiple step multivariate statistics for more than 500 cereal samples collected over 2 years from 17 sampling sites across Europe representing an extensive range of geographical and environmental characteristics. 相似文献
116.
Bernhard Beinhofer 《European Journal of Forest Research》2010,129(5):921-934
This study analysed whether the production of high-quality assortments, saw timber and pulpwood in Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) stands leads to effects of risk compensation. Mixtures of conventionally treated pruned and non-pruned stands, as well as
mixtures of stands which had been optimized concerning the occurrence of assortments and financial criteria were considered.
The price simulation was done by bootstrapping to avoid the assumption of a certain distribution of timber prices, and to
preserve the correlations of the timber prices from different assortments. The financial valuation was carried out with annuities
within a Monte Carlo simulation with 10,000 repetitions. To quantify the effect of natural hazards, the calculations were
repeated with and without this factor. Minimum risk portfolios were determined and optimization performed using both a utility
function as well as the value-at-risk approach. The mixtures with minimum risk were dominated by pine stands, as they are
less affected by natural hazards and prices for pine timber have a lower volatility, although pine timber prices are generally
lower compared to that of spruce timber. These pine dominated portfolios showed risk reductions up to 92% compared to the
riskiest single stand, but the annuities were reduced even more. In contrast to this, the portfolios optimized with the utility
function and the value-at-risk approach consisted of spruce stands. These spruce portfolios showed an efficient risk reduction
of up to 60%. Additionally, higher annuities and larger diversification effects occurred in the portfolios containing the
optimized stands. Integrating the risk of natural hazards, the annuities decreased, as did the correlation of the annuities
of the different stands, while risk increased. Altogether these effects led to higher relative risk reductions when forming
optimal portfolios. These results indicate that producing different assortments of spruce and pine leads to risk compensation,
especially when considering portfolios consisting of optimized stands. 相似文献
117.
Self-organizing maps (SOMs) are an advanced neural networks application. SOMs were applied for the spatially explicit estimation of forest carbon stocks for a test region in Thuringia (Germany). The approach utilizes in situ national forest inventory data and satellite remote sensing data (Landsat 7 ETM+) and provides maps showing a high-resolution spatial distribution of forest carbon stocks. The generated maps are compared to alternative estimates obtained by the k-nearest neighbour (kNN) method—a remote sensing based carbon assessment. Beside maps the SOM- and kNN-approaches were utilized to calculate statistical estimates of carbon stock and growing stock. The statistical estimates were validated by calculating bias and mean square errors with reference to in situ assessments. 相似文献
118.
Chelal John Hau Bernhard 《European journal of plant pathology / European Foundation for Plant Pathology》2015,143(3):461-471
European Journal of Plant Pathology - A model simulating the progress of powdery mildew coupled to the growth dynamics of tomato, with a time step of 1&;nbsp;day, is developed. The model is... 相似文献
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