Local adaptation in natural European host grass populations with asymmetric symbiosis

Recent work on microbiomes is revealing the wealth and importance of plant-microbe interactions. Microbial symbionts are proposed to have profound effects on fitness of their host plants and vice versa, especially when their fitness is tightly linked. Here we studied local adaptation of host plants and possible fitness contribution of such symbiosis in the context of abiotic environmental factors. We conducted a four-way multi-year reciprocal transplant experiment with natural populations of the perennial grass Festuca rubra s.l. from northern and southern Finland, Faroe Islands and Spain. We included F. rubra with and without transmitted symbiotic fungus Epichloë that is vertically transmitted via host seed. We found local adaptation across the European range, as evidenced by higher host fitness of the local geographic origin compared with nonlocals at three of the four studied sites, suggesting that selection pressures are driving evolution in different directions. Abiotic factors did not result in strong fitness effects related to Epichloë symbiosis, indicating that other factors such as herbivory are more likely to contribute to fitness differences between plants naturally occurring with or without Epichloë. Nevertheless, in the case of asymmetric symbiosis that is obligatory for the symbiont, abiotic conditions that affect performance of the host, may also cause selective pressure for the symbiont.</p

Data on litter quality of host grass plants with and without fungal endophytes

Certain Pooideae species form persistent symbiosis with fungal endophytes of Epichloë genus. Although endophytes are known to impact the ecology and evolution of host species, their effects on parameters related with quality of plant biomass has been elusive. This article provides information about parameters related with the quality of plant litter biomass of two important grass species (Schedonorus phoenix and Schedonorus pratensis) affected by the symbiosis with fungal endophytes (Epichloë coenophiala and Epichloë uncinata, respectively). Four population origins of S. phoenix and one of S. pratensis were included. Mineral, biochemical and structural parameters were obtained from three samples per factors combination [species (and population origin)×endophyte]. This data can be potentially used in other studies which, by means of 'data reanalyzing' or meta-analysis, attempt to find generalizations about endophyte effects on host plant litter biomass. The present data is associated with the research article "Role of foliar fungal endophytes on litter decomposition among species and population origins" (Gundel et al., In preparation) [1]

Breakdown of stabilization of atoms interacting with intense, high-frequency laser pulses

Published versio

Atoms interacting with intense, high-frequency laser pulses: Effect of the magnetic-field component on atomic stabilization

Published versio

A spectroscopy approach to the study of virus infection in the endophytic fungus Epichloë festucae

<p>Abstract</p> <p>Background</p> <p>In this work we propose a rapid method based on visible and near-infrared (Vis-NIR) spectroscopy to determine the occurrence of double-stranded RNA (dsRNA) viruses in <it>Epichloë festucae </it>strains isolated from <it>Festuca rubra </it>plants. In addition, we examined the incidence of infections by <it>E. festucae </it>in populations of <it>F. rubra </it>collected in natural grasslands of Western Spain.</p> <p>Methods</p> <p>Vis-NIR spectra (400-2498 nm) from 124 virus-infected and virus-free <it>E. festucae </it>isolates were recorded directly from ground and freeze-dried mycelium. To estimate how well the spectra for uninfected and infected fungal samples could be differentiated, we used partial least-squares discriminant analysis (PLS1-DA) and several data pre-treatments to develop calibration models.</p> <p>Results</p> <p>Applying the best regression model, obtained with two sampling years and using standard normal variate (SNV) combined with first derivative transformation to a new validating data set (42 samples), we obtained a correct classification for 75% of the uninfected isolates and up to 86% of the infected isolates.</p> <p>Conclusions</p> <p>The results obtained suggest that Vis-NIR spectroscopy is a promising technology for detection of viral infections in fungal samples when an alternative faster approach is desirable. It provides a tool adequately exact and more time- and cost-saving than the conventional reference analysis.</p

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference