@article{MurganBeyerKotliaretal.2013, author = {Murgan, Ilina and Beyer, Sonja and Kotliar, Konstantin and Weber, Lutz and Bechtold-Dalla Pozza, Susanne and Dalla Pozza, Robert and Wegner, Aharon and Sitnikova, Diana and Stock, Konrad and Heemann, Uwe and Schmaderer, Christoph and Baumann, M.}, title = {Arterial and Retinal Vascular Changes in Hypertensive and Prehypertensive Adolescents}, series = {American Journal of Hypertension}, volume = {26}, journal = {American Journal of Hypertension}, number = {3}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1941-7225}, pages = {400 -- 408}, year = {2013}, language = {de} } @article{BehbahaniTranJockenhoeveletal.2011, author = {Behbahani, Mehdi and Tran, L. and Jockenh{\"o}vel, S. and Behr, M. and Mottaghy, K.}, title = {Numerical prediction of thrombocyte reactions for application to a vascular flow model}, series = {British Journal of Surgery}, volume = {98}, journal = {British Journal of Surgery}, number = {S5}, publisher = {Oxford University Press}, address = {Oxford}, isbn = {1365-2168}, pages = {S17}, year = {2011}, language = {en} } @article{GoedhuysJanzMohnen2014, author = {Goedhuys, Micheline and Janz, Norbert and Mohnen, Pierre}, title = {Knowledge-based productivity in "low-tech" industries: evidence from firms in developing countries}, series = {Industrial and corporate change}, volume = {23}, journal = {Industrial and corporate change}, number = {1}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1464-3650 (E-Journal); 0960-6491 (Print)}, doi = {10.1093/icc/dtt006}, pages = {1 -- 23}, year = {2014}, abstract = {Using firm-level data from five developing countries—Brazil, Ecuador, South Africa, Tanzania, and Bangladesh—and three industries—food processing, textiles, and the garments and leather products—this article examines the importance of various sources of knowledge for explaining productivity and formally tests whether sector- or country-specific characteristics dominate these relationships. Knowledge sources driving productivity appear mainly sector specific. Also differences in the level of development affect the effectiveness of knowledge sources. In the food processing sector, firms with higher educated managers are more productive, and in least-developed countries, additionally those with technology licenses and imported machinery and equipment. In the capital-intensive textiles sector, productivity is higher in firms that conduct R\&D. In the garments and leather products sector, higher education of the managers, licensing, and R\&D raise productivity.}, language = {en} } @article{EilmannSterckWegneretal.2014, author = {Eilmann, Britta and Sterck, Frank J. and Wegner, L. and de Vries, Sven M. G. and von Arx, G. and Mohren, Godefridus M. J. and den Ouden, Jan and Sass-Klaassen, Ute G. W.}, title = {Wood structural differences between northern and southern beech provenances growing at a moderate site}, series = {Tree Physiology}, volume = {34}, journal = {Tree Physiology}, number = {8}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1758-4469 (Online)}, doi = {10.1093/treephys/tpu069}, pages = {882 -- 893}, year = {2014}, language = {en} } @article{EilmannRigling2012, author = {Eilmann, Britta and Rigling, Andreas}, title = {Tree-growth analyses to estimate tree species' drought tolerance}, series = {Tree Physiology}, volume = {32}, journal = {Tree Physiology}, number = {2}, editor = {Abrams, Marc}, publisher = {Oxford University Press}, address = {Oxford}, issn = {0829-318X (Print)}, doi = {10.1093/treephys/tps004}, pages = {178 -- 187}, year = {2012}, abstract = {Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree species' potential for surviving future aggravated environmental conditions is rather demanding. The aim of this study was to find a tree-ring-based method suitable for identifying very drought-tolerant species, particularly potential substitute species for Scots pine (Pinus sylvestris L.) in Valais. In this inner-Alpine valley, Scots pine used to be the dominating species for dry forests, but today it suffers from high drought-induced mortality. We investigate the growth response of two native tree species, Scots pine and European larch (Larix decidua Mill.), and two non-native species, black pine (Pinus nigra Arnold) and Douglas fir (Pseudotsuga menziesii Mirb. var. menziesii), to drought. This involved analysing how the radial increment of these species responded to increasing water shortage (abandonment of irrigation) and to increasingly frequent drought years. Black pine and Douglas fir are able to cope with drought better than Scots pine and larch, as they show relatively high radial growth even after irrigation has been stopped and a plastic growth response to drought years. European larch does not seem to be able to cope with these dry conditions as it lacks the ability to recover from drought years. The analysis of trees' short-term response to extreme climate events seems to be the most promising and suitable method for detecting how tolerant a tree species is towards drought. However, combining all the methods used in this study provides a complete picture of how water shortage could limit species.}, language = {en} } @article{EilmannZweifelBuchmannetal.2011, author = {Eilmann, Britta and Zweifel, Roman and Buchmann, Nina and Graf Pannatier, Elisabeth and Rigling, Andreas}, title = {Drought alters timing, quantity, and quality of wood formation in Scots pine}, series = {Journal of Experimental Botany}, volume = {62}, journal = {Journal of Experimental Botany}, number = {8}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1460-2431 (Online)}, doi = {10.1093/jxb/erq443}, pages = {2763 -- 2771}, year = {2011}, language = {en} } @article{MichalakNacerddinePietersenetal.2013, author = {Michalak, Ewa Malgorzata and Nacerddine, Karim and Pietersen, Alexandra and Beuger, Vincent and Pawlitzky, Inka and Cornelissen-Steijger, Paulien and Wientjens, Ellen and Tanger, Ellen and Seibler, Jost and Lohuizen, Maarten van and Jonkers, Jos}, title = {Polycomb group gene Ezh2 regulates mammary gland morphogenesis and maintains the luminal progenitor pool}, series = {Stem Cells}, volume = {Vol 31}, journal = {Stem Cells}, number = {9}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1549-4918}, doi = {10.1002/stem.1437}, pages = {1910 -- 1920}, year = {2013}, language = {en} } @article{VogtMottaghyRathetal.2014, author = {Vogt, C. and Mottaghy, Darius and Rath, V. and Marquart, G. and Dijkshoorn, L. and Wolf, A. and Clauser, C.}, title = {Vertical variation in heat flow on the Kola Peninsula: palaeoclimate or fluid flow?}, series = {Geophysical Journal International}, volume = {199}, journal = {Geophysical Journal International}, number = {2}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1365-246X}, doi = {10.1093/gji/ggu282}, pages = {829 -- 843}, year = {2014}, abstract = {Following earlier studies, we present forward and inverse simulations of heat and fluid transport of the upper crust using a local 3-D model of the Kola area. We provide best estimates for palaeotemperatures and permeabilities, their errors and their dependencies. Our results allow discriminating between the two mentioned processes to a certain extent, partly resolving the non-uniqueness of the problem. We find clear indications for a significant contribution of advective heat transport, which, in turn, imply only slightly lower ground surface temperatures during the last glacial maximum relative to the present value. These findings are consistent with the general background knowledge of (i) the fracture zones and the corresponding fluid movements in the bedrock and (ii) the glacial history of the Kola area.}, language = {en} } @article{JahnkeRousselHombachetal.2016, author = {Jahnke, Siegfried and Roussel, Johanna and Hombach, Thomas and Kochs, Johannes and Fischbach, Andreas and Huber, Gregor and Scharr, Hanno}, title = {phenoSeeder - A robot system for automated handling and phenotyping of individual seeds}, series = {Plant physiology}, volume = {172}, journal = {Plant physiology}, number = {3}, publisher = {Oxford University Press}, address = {Oxford}, issn = {0032-0889}, doi = {10.1104/pp.16.01122}, pages = {1358 -- 1370}, year = {2016}, abstract = {The enormous diversity of seed traits is an intriguing feature and critical for the overwhelming success of higher plants. In particular, seed mass is generally regarded to be key for seedling development but is mostly approximated by using scanning methods delivering only two-dimensional data, often termed seed size. However, three-dimensional traits, such as the volume or mass of single seeds, are very rarely determined in routine measurements. Here, we introduce a device named phenoSeeder, which enables the handling and phenotyping of individual seeds of very different sizes. The system consists of a pick-and-place robot and a modular setup of sensors that can be versatilely extended. Basic biometric traits detected for individual seeds are two-dimensional data from projections, three-dimensional data from volumetric measures, and mass, from which seed density is also calculated. Each seed is tracked by an identifier and, after phenotyping, can be planted, sorted, or individually stored for further evaluation or processing (e.g. in routine seed-to-plant tracking pipelines). By investigating seeds of Arabidopsis (Arabidopsis thaliana), rapeseed (Brassica napus), and barley (Hordeum vulgare), we observed that, even for apparently round-shaped seeds of rapeseed, correlations between the projected area and the mass of seeds were much weaker than between volume and mass. This indicates that simple projections may not deliver good proxies for seed mass. Although throughput is limited, we expect that automated seed phenotyping on a single-seed basis can contribute valuable information for applications in a wide range of wild or crop species, including seed classification, seed sorting, and assessment of seed quality.}, language = {en} } @article{BialonskiCaronSchloenetal.2016, author = {Bialonski, Stephan and Caron, David A. and Schloen, Julia and Feudel, Ulrike and Kantz, Holger and Moorthi, Stefanie D.}, title = {Phytoplankton dynamics in the Southern California Bight indicate a complex mixture of transport and biology}, series = {Journal of Plankton Research}, volume = {38}, journal = {Journal of Plankton Research}, number = {4}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1464-3774}, doi = {10.1093/plankt/fbv122}, pages = {1077 -- 1091}, year = {2016}, abstract = {The stimulation and dominance of potentially harmful phytoplankton taxa at a given locale and time are determined by local environmental conditions as well as by transport to or from neighboring regions. The present study investigated the occurrence of common harmful algal bloom (HAB) taxa within the Southern California Bight, using cross-correlation functions to determine potential dependencies between HAB taxa and environmental factors, and potential links to algal transport via local hydrography and currents. A simulation study, in which Lagrangian particles were released, was used to assess travel times due to advection by prevailing ocean currents in the bight. Our results indicate that transport of some taxa may be an important mechanism for the expansion of their distributions into other regions, which was supported by mean travel times derived from our simulation study and other literature on ocean currents in the Southern California Bight. In other cases, however, phytoplankton dynamics were rather linked to local environmental conditions, including coastal upwelling events. Overall, our study shows that complex current patterns in the Southern California Bight may contribute significantly to the formation and expansion of HABs in addition to local environmental factors determining the spatiotemporal dynamics of phytoplankton blooms.}, language = {en} } @article{LuisierLempiaeinenScherbichleretal.2014, author = {Luisier, Rapha{\"e}lle and Lempi{\"a}inen, Harri and Scherbichler, Nina and Braeuning, Albert and Geissler, Miriam and Dubost, Valerie and M{\"u}ller, Arne and Scheer, Nico and Chibout, Salah-Dine and Hara, Hisanori and Picard, Frank and Theil, Diethilde and Couttet, Philippe and Vitobello, Antonio and Grenet, Olivier and Grasl-Kraupp, Bettina and Ellinger-Ziegelbauer, Heidrung and Thomson, John P. and Meehan, Richard R. and Elcombe, Clifford R. and Henderson, Colin J. and Wolf, C. Roland and Schwarz, Michael and Moulin, Pierre and Terranova, Remi and Moggs, Jonathan G.}, title = {Phenobarbital Induces Cell Cycle Transcriptional Responses in Mouse Liver Humanized for Constitutive Androstane and Pregnane X Receptors}, series = {Toxicological Sciences}, volume = {139}, journal = {Toxicological Sciences}, number = {2}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1094-2025}, doi = {https://doi.org/10.1093/toxsci/kfu038}, pages = {501 -- 511}, year = {2014}, abstract = {The constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) are closely related nuclear receptors involved in drug metabolism and play important roles in the mechanism of phenobarbital (PB)-induced rodent nongenotoxic hepatocarcinogenesis. Here, we have used a humanized CAR/PXR mouse model to examine potential species differences in receptor-dependent mechanisms underlying liver tissue molecular responses to PB. Early and late transcriptomic responses to sustained PB exposure were investigated in liver tissue from double knock-out CAR and PXR (CARᴷᴼ-PXRᴷᴼ), double humanized CAR and PXR (CARʰ-PXRʰ), and wild-type C57BL/6 mice. Wild-type and CARʰ-PXRʰ mouse livers exhibited temporally and quantitatively similar transcriptional responses during 91 days of PB exposure including the sustained induction of the xenobiotic response gene Cyp2b10, the Wnt signaling inhibitor Wisp1, and noncoding RNA biomarkers from the Dlk1-Dio3 locus. Transient induction of DNA replication (Hells, Mcm6, and Esco2) and mitotic genes (Ccnb2, Cdc20, and Cdk1) and the proliferation-related nuclear antigen Mki67 were observed with peak expression occurring between 1 and 7 days PB exposure. All these transcriptional responses were absent in CARᴷᴼ-PXRᴷᴼ mouse livers and largely reversible in wild-type and CARʰ-PXRʰ mouse livers following 91 days of PB exposure and a subsequent 4-week recovery period. Furthermore, PB-mediated upregulation of the noncoding RNA Meg3, which has recently been associated with cellular pluripotency, exhibited a similar dose response and perivenous hepatocyte-specific localization in both wild-type and CARʰ-PXRʰ mice. Thus, mouse livers coexpressing human CAR and PXR support both the xenobiotic metabolizing and the proliferative transcriptional responses following exposure to PB.}, language = {en} } @article{LempiaeinenCouttetBolognanietal.2012, author = {Lempi{\"a}inen, Harri and Couttet, Philippe and Bolognani, Federico and M{\"u}ller, Arne and Dubost, Val{\´e}rie and Luisier, Rapha{\"e}lle and Rio-Espinola, Alberto del and Vitry, Veronique and Unterberger, Elif B. and Thomson, John P. and Treindl, Fridolin and Metzger, Ute and Wrzodek, Clemens and Hahne, Florian and Zollinger, Tulipan and Brasa, Sarah and Kalteis, Magdalena and Marcellin, Magali and Giudicelli, Fanny and Braeuning, Albert and Morawiec, Laurent and Zamurovic, Natasa and L{\"a}ngle, Ulrich and Scheer, Nico and Sch{\"u}beler, Dirk and Goodman, Jay and Chibout, Salah-Dine and Marlowe, Jennifer and Theil, Dietlinde and Heard, David J. and Grenet, Olivier and Zell, Andreas and Templin, Markus F. and Meehan, Richard R. and Wolf, Roland C. and Elcombe, Clifford R. and Schwarz, Michael and Moulin, Pierre and Terranova, R{\´e}mi and Moggs, Jonathan G.}, title = {Identification of Dlk1-Dio3 imprinted gene cluster non-coding RNAs as novel candidate biomarkers for liver tumor promotion}, series = {Toxicological Sciences}, volume = {131}, journal = {Toxicological Sciences}, number = {2}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1094-2025}, doi = {10.1093/toxsci/kfs303}, pages = {375 -- 386}, year = {2012}, abstract = {The molecular events during nongenotoxic carcinogenesis and their temporal order are poorly understood but thought to include long-lasting perturbations of gene expression. Here, we have investigated the temporal sequence of molecular and pathological perturbations at early stages of phenobarbital (PB) mediated liver tumor promotion in vivo. Molecular profiling (mRNA, microRNA [miRNA], DNA methylation, and proteins) of mouse liver during 13 weeks of PB treatment revealed progressive increases in hepatic expression of long noncoding RNAs and miRNAs originating from the Dlk1-Dio3 imprinted gene cluster, a locus that has recently been associated with stem cell pluripotency in mice and various neoplasms in humans. PB induction of the Dlk1-Dio3 cluster noncoding RNA (ncRNA) Meg3 was localized to glutamine synthetase-positive hypertrophic perivenous hepatocytes, sug- gesting a role for β-catenin signaling in the dysregulation of Dlk1-Dio3 ncRNAs. The carcinogenic relevance of Dlk1-Dio3 locus ncRNA induction was further supported by in vivo genetic dependence on constitutive androstane receptor and β-catenin pathways. Our data identify Dlk1-Dio3 ncRNAs as novel candidate early biomarkers for mouse liver tumor promotion and provide new opportunities for assessing the carcinogenic potential of novel compounds.}, language = {en} } @article{WerfelGuenthnerHapfelmeieretal.2022, author = {Werfel, Stanislas and G{\"u}nthner, Roman and Hapfelmeier, Alexander and Hanssen, Henner and Kotliar, Konstantin and Heemann, Uwe and Schmaderer, Christoph}, title = {Identification of cardiovascular high-risk groups from dynamic retinal vessel signals using untargeted machine learning}, series = {Cardiovascular Research}, volume = {118}, journal = {Cardiovascular Research}, number = {2}, editor = {Guzik, Tomasz J.}, publisher = {Oxford University Press}, address = {Oxford}, issn = {0008-6363}, doi = {10.1093/cvr/cvab040}, pages = {612 -- 621}, year = {2022}, abstract = {Dynamic retinal vessel analysis (DVA) provides a non-invasive way to assess microvascular function in patients and potentially to improve predictions of individual cardiovascular (CV) risk. The aim of our study was to use untargeted machine learning on DVA in order to improve CV mortality prediction and identify corresponding response alterations.}, language = {en} } @article{RossPlummerRodeetal.2010, author = {Ross, Jillian and Plummer, Simon M. and Rode, Anja and Scheer, Nico and Bower, Conrad C. and Vogel, Ortwin and Henderson, Colin J. and Wolf, C. Roland and Elcombe, Clifford R.}, title = {Human constitutive androstane receptor (CAR) and pregnane X receptor (PXR) support the hypertrophic but not the hyperplastic response to the murine nongenotoxic hepatocarcinogens phenobarbital and chlordane in vivo}, series = {Toxicological Sciences}, volume = {116}, journal = {Toxicological Sciences}, number = {2}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1096-0929}, doi = {10.1093/toxsci/kfq118}, pages = {452 -- 466}, year = {2010}, abstract = {Mouse nongenotoxic hepatocarcinogens phenobarbital (PB) and chlordane induce hepatomegaly characterized by hypertrophy and hyperplasia. Increased cell proliferation is implicated in the mechanism of tumor induction. The relevance of these tumors to human health is unclear. The xenoreceptors, constitutive androstane receptors (CARs), and pregnane X receptor (PXR) play key roles in these processes. Novel "humanized" and knockout models for both receptors were developed to investigate potential species differences in hepatomegaly. The effects of PB (80 mg/kg/4 days) and chlordane (10 mg/kg/4 days) were investigated in double humanized PXR and CAR (huPXR/huCAR), double knockout PXR and CAR (PXRKO/CARKO), and wild-type (WT) C57BL/6J mice. In WT mice, both compounds caused increased liver weight, hepatocellular hypertrophy, and cell proliferation. Both compounds caused alterations to a number of cell cycle genes consistent with induction of cell proliferation in WT mice. However, these gene expression changes did not occur in PXRKO/CARKO or huPXR/huCAR mice. Liver hypertrophy without hyperplasia was demonstrated in the huPXR/huCAR animals in response to both compounds. Induction of the CAR and PXR target genes, Cyp2b10 and Cyp3a11, was observed in both WT and huPXR/huCAR mouse lines following treatment with PB or chlordane. In the PXRKO/CARKO mice, neither liver growth nor induction of Cyp2b10 and Cyp3a11 was seen following PB or chlordane treatment, indicating that these effects are CAR/PXR dependent. These data suggest that the human receptors are able to support the chemically induced hypertrophic responses but not the hyperplastic (cell proliferation) responses. At this time, we cannot be certain that hCAR and hPXR when expressed in the mouse can function exactly as the genes do when they are expressed in human cells. However, all parameters investigated to date suggest that much of their functionality is maintained.}, language = {en} } @article{VogtMottaghyWolfetal.2010, author = {Vogt, C. and Mottaghy, Darius and Wolf, A. and Rath, V. and Pechnig, R. and Clauser, C.}, title = {Reducing temperature uncertainties by stochastic geothermal reservoir modelling}, series = {Geophysical Journal International}, volume = {181}, journal = {Geophysical Journal International}, number = {1}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1365-246X}, doi = {10.1111/j.1365-246X.2009.04498.x}, pages = {321 -- 333}, year = {2010}, abstract = {Quantifying and minimizing uncertainty is vital for simulating technically and economically successful geothermal reservoirs. To this end, we apply a stochastic modelling sequence, a Monte Carlo study, based on (i) creating an ensemble of possible realizations of a reservoir model, (ii) forward simulation of fluid flow and heat transport, and (iii) constraining post-processing using observed state variables. To generate the ensemble, we use the stochastic algorithm of Sequential Gaussian Simulation and test its potential fitting rock properties, such as thermal conductivity and permeability, of a synthetic reference model and—performing a corresponding forward simulation—state variables such as temperature. The ensemble yields probability distributions of rock properties and state variables at any location inside the reservoir. In addition, we perform a constraining post-processing in order to minimize the uncertainty of the obtained distributions by conditioning the ensemble to observed state variables, in this case temperature. This constraining post-processing works particularly well on systems dominated by fluid flow. The stochastic modelling sequence is applied to a large, steady-state 3-D heat flow model of a reservoir in The Hague, Netherlands. The spatial thermal conductivity distribution is simulated stochastically based on available logging data. Errors of bottom-hole temperatures provide thresholds for the constraining technique performed afterwards. This reduce the temperature uncertainty for the proposed target location significantly from 25 to 12 K (full distribution width) in a depth of 2300 m. Assuming a Gaussian shape of the temperature distribution, the standard deviation is 1.8 K. To allow a more comprehensive approach to quantify uncertainty, we also implement the stochastic simulation of boundary conditions and demonstrate this for the basal specific heat flow in the reservoir of The Hague. As expected, this results in a larger distribution width and hence, a larger, but more realistic uncertainty estimate. However, applying the constraining post-processing the uncertainty is again reduced to the level of the post-processing without stochastic boundary simulation. Thus, constraining post-processing is a suitable tool for reducing uncertainty estimates by observed state variables.}, language = {en} } @article{DobbertinEilmannBleuleretal.2010, author = {Dobbertin, Matthias and Eilmann, Britta and Bleuler, Peter and Giuggiola, Arnaud and Graf Pannatier, Elisabeth and Landolt, Werner and Schleppi, Patrick and Rigling, Andreas}, title = {Effect of irrigation on needle morphology, shoot and stem growth in a drought-exposed Pinus sylvestris forest}, series = {Tree Physiology}, volume = {30}, journal = {Tree Physiology}, number = {3}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1758-4469 (Online)}, doi = {10.1093/treephys/tpp123}, pages = {346 -- 360}, year = {2010}, abstract = {In Valais, Switzerland, Scots pines (Pinus sylvestris L.) are declining, mainly following drought. To assess the impact of drought on tree growth and survival, an irrigation experiment was initiated in 2003 in a mature pine forest, approximately doubling the annual precipitation. Tree crown transparency (lack of foliage) and leaf area index (LAI) were annually assessed. Seven irrigated and six control trees were felled in 2006, and needles, stem discs and branches were taken for growth analysis. Irrigation in 2004 and 2005, both with below-average precipitation, increased needle size, area and mass, stem growth and, with a 1-year delay, shoot length. This led to a relative decrease in tree crown transparency (-14\%) and to an increase in stand LAI (+20\%). Irrigation increased needle length by 70\%, shoot length by 100\% and ring width by 120\%, regardless of crown transparency. Crown transparency correlated positively with mean needle size, shoot length and ring width and negatively with specific leaf area. Trees with high crown transparency (low growth, short needles) experienced similar increases in needle mass and growth with irrigation than trees with low transparency (high growth, long needles), indicating that seemingly declining trees were able to 'recover' when water supply became sufficient. A simple drought index before and during the irrigation explained most of the variation found in the parameters for both irrigated and control trees.}, language = {en} } @article{RiglingEilmannKoechlietal.2010, author = {Rigling, Andreas and Eilmann, Britta and Koechli, Roger and Dobbertin, Matthias}, title = {Mistletoe-induced crown degradation in Scots pine in a xeric environment}, volume = {30}, number = {7}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1758-4469 (Online)}, doi = {10.1093/treephys/tpq038}, pages = {845 -- 832}, year = {2010}, abstract = {Increasing Scots pine (Pinus sylvestris L.) mortality has been recently observed in the dry inner valleys of the European Alps. Besides drought, infection with pine mistletoe (Viscum album ssp. austriacum) seems to play an important role in the mortality dynamics of Scots pines, but how mistletoes promote pine decline remains unclear. To verify whether pine mistletoe infection weakens the host via crown degradation, as observed for dwarf mistletoes, we studied the negative effects of pine mistletoe infestation on the photosynthetic tissues and branch growth of pairs of infested and non-infested branches. Pine mistletoe infection leads to crown degradation in its host by reducing the length, the radial increment, the ramification, the needle length and the number of needle years of the infested branches. This massive loss in photosynthetic tissue results in a reduction in primary production and a subsequent decrease in carbohydrate availability. The significant reduction in needle length due to mistletoe infection is an indication for a lower water and nutrient availability in infested branches. Thus, mistletoe infection might lead to a decrease in the availability of water and carbohydrates, the two most important growth factors, which are already shortened due to the chronic drought situation in the area. Therefore, pine mistletoe increases the risk of drought-induced mortality of its host when growing in a xeric environment.}, language = {en} }