Species richness, abundance and phenology of fungal fruit bodies over 21 years in a Swiss forest plot

Fungal fruit bodies were surveyed on a plot area of 1500 m2 from 1975¿99 (excluding 1980¿83) in the fungal reserve La Chaneaz in western Switzerland. Fruit bodies were identified and counted on a weekly basis. Species richness and abundances varied strongly between years. More than 400 species were encountered. Many species were transient; particularly rich years showed species occurring for only one year. This indicates that the number of species will substantially increase if the survey is continued. Within years, the species richness, abundances and periods of fruiting were tightly correlated. The abundance data of species within a year seemed symmetrically distributed over their fruiting period. The relation between species richness and abundances within years was studied by fitting species-abundance plots, known from numerical ecology. The surface area under the curves was taken as a parameter for ecological/fungal diversity. Productivity was correlated with the precipitation from June until October. The time of fruit body appearance was correlated with the temperatures in July and August. As groups, mycorrhizal and saprotrophic species behaved similarly over the years. The productivity of species was compared with their distribution in The Netherlands indicating a correlation between the level of local abundance and the geographic range of specie

Physiology of mycelial growth of the mycorrhizal mushroom Cantharellus cibarius Fr.

In this thesis in vitro growth of mycelium of Cantharellus cibarius Fr. is described as the first step in the domestication of this edible mycorrhizal mushroom. A collection of pure cultures was obtained and the requirements for vegetative growth were determined.IsolationA culture collection of 33 strains was obtained by isolation from spores or by cultivation from fruit body tissue. Isolation was technically not difficult. However, many attempts were required because only very few spores germinated and only few tissue explants remained free from contaminants. In addition the incubation time required for successful isolation is long, viz. three months. DNA/DNA hybridization experiments proved the identity of the cultures. The biological variation in the strain collection was Illustrated by differences in growth parameters such as relative growth rate.Growth requirementsThe objects of the experiments were the development of an optimal nutrient solution for mycelial growth and the elucidation of root effects on growth. In these studies two kinds of inoculum were used: mycelial tufts and hyphal fragments. These inocula showed different requirements. Mycelial tufts grew strongly in Fries medium supplemented with micro- minerals. Hyphal fragments showed more extensive requirements; their growth was limited to the development of small and thin mycelia. The modified Fries medium and incubation at 20° appeared almost optimal for growth of mycelial tufts. In sterilization of the nutrient solution, filtration is of major importance. Emersed growth was found to be better than standard, submersed incubation. Fungal growth reacts strongly to various additions to the medium. The specific growth rate was low. It could not beIncreased by the use of other media or by addition of possible growth factors to modified Fries medium. The specific growth rates of the tested strains increased in the course of the studies independently of nutrition or incubation conditions.Development of hyphal fragments into strongly growing mycelium at first required the presence of a living root in the nutrient solution. Three observations indicated that the factor(s) involved could be produced by the fungus itself:- the specific growth rates of mycelial tufts in the absence of roots and of hyphal fragments in the presence of roots were identical;- kinetics of growth of hyphal fragments showed that a root effect was limited to the duration of the lag phase;- hyphae brought into intimate mutual contact grew as strongly as a mycelial tuft.The unknown growth factor(s) was volatile in nature. It could be replaced by carbon dioxide. A 0.5% concentration of CO 2 in the incubation atmosphere is sufficient for strong growth of hyphal fragments.CO 2 could be replaced by a mixture of malic acid, thymine, and Tween 80. This suggests that CO 2 fixation reactions involved in the replenishment of Krebs cycle intermediates, in the synthesis of pyrimidines, and in the synthesis of fatty acids are growth limiting for hyphal fragments.On the one hand, the homogeneous growth of hyphal fragments, described in this thesis, allows the second step in the domestication of this mushroom, viz. the study of fruit body formation. On the other hand, the analysis of the growth requirements of these fragments further elucidates the ecological nature of the mycorrhizal relationship between C. cibarius and plant roots. The view that the fungus is supplemented with specific growth factor(s) is not supported. The production of carbon dioxide by roots enables the establishment of the fungus in the rhizosphere

De stroom van grondstoffen en reststoffen in de biologische champignonteelt

Rapport over de positie van de biologische paddestoelenteelt op intersectoraal en (inter)-regionaal niveau. Het overzicht in tabel- en schemavorm van de stromen grondstoffen en producten verduidelijkt de intersectorale positie van de champignonteelt. Dit kan een aanzet zijn bij het signaleren en oplossen van knelpunten in de grondstoffenvoorziening in de biologische champignonteelt en in de afzet van restproducten in andere sectore

Masterplan voeding : water en voeding voor champignons: kansen en noodzaak voor innovatie

Champignons worden nu geteeld op compost die bestaat uit stro-rijke paardenmest, kippenmest, gips en water. Voordelen van deze ingrediënten zijn dat ze tot nu toe voldoende aanwezig zijn tegen lage kosten. Het composteringsproces is op zich een redelijk goed beheersbaar proces met een redelijk voorspelbare uitkomst. Er zijn echter voldoende redenen aan te voeren waarom innovatie op substraat kansen biedt voor het versterken van de Nederlandse concurrentiepositie

Macrofungal diversity in Colombian Amazon forests varies with regions and regimes of disturbance

Here we present the results of fungal biodiversity studies from some selected Colombian Amazon forests in relationship to plant biodiversity and successional stages after slash and burn agriculture. Macrofungal diversity was found to differ between forests occurring in two regions (Araracuara vs Amacayacu) as well as between flooded forests and terra firme forests in the Amacayacu region. Macrofungal biodiversity differed between regeneration states of different age in the Araracuara region. Suitable substrates, especially dead wood that occurred as a result of recent slash and burn agriculture, resulted in the formation of many sporocarps of wood-inhabiting species. Putative ectomycorrhizal species were found in a dipterocarp forest. Fifty two percent of the macrofungal species could not be identified to the species level, but could be assigned to a genus, and it is likely that a significant portion of these represent species new to science. Long term studies are needed to obtain a comprehensive and complete understanding of the diversity and functioning of mycobiota in Amazon forest ecosystems

ASCR/HEP Exascale Requirements Review Report

This draft report summarizes and details the findings, results, and recommendations derived from the ASCR/HEP Exascale Requirements Review meeting held in June, 2015. The main conclusions are as follows. 1) Larger, more capable computing and data facilities are needed to support HEP science goals in all three frontiers: Energy, Intensity, and Cosmic. The expected scale of the demand at the 2025 timescale is at least two orders of magnitude -- and in some cases greater -- than that available currently. 2) The growth rate of data produced by simulations is overwhelming the current ability, of both facilities and researchers, to store and analyze it. Additional resources and new techniques for data analysis are urgently needed. 3) Data rates and volumes from HEP experimental facilities are also straining the ability to store and analyze large and complex data volumes. Appropriately configured leadership-class facilities can play a transformational role in enabling scientific discovery from these datasets. 4) A close integration of HPC simulation and data analysis will aid greatly in interpreting results from HEP experiments. Such an integration will minimize data movement and facilitate interdependent workflows. 5) Long-range planning between HEP and ASCR will be required to meet HEP's research needs. To best use ASCR HPC resources the experimental HEP program needs a) an established long-term plan for access to ASCR computational and data resources, b) an ability to map workflows onto HPC resources, c) the ability for ASCR facilities to accommodate workflows run by collaborations that can have thousands of individual members, d) to transition codes to the next-generation HPC platforms that will be available at ASCR facilities, e) to build up and train a workforce capable of developing and using simulations and analysis to support HEP scientific research on next-generation systems.Comment: 77 pages, 13 Figures; draft report, subject to further revisio

The Entropy Production Fluctuation Theorem and the Nonequilibrium Work Relation for Free Energy Differences

There are only a very few known relations in statistical dynamics that are valid for systems driven arbitrarily far-from-equilibrium. One of these is the fluctuation theorem, which places conditions on the entropy production probability distribution of nonequilibrium systems. Another recently discovered far-from-equilibrium expression relates nonequilibrium measurements of the work done on a system to equilibrium free energy differences. In this paper, we derive a generalized version of the fluctuation theorem for stochastic, microscopically reversible dynamics. Invoking this generalized theorem provides a succinct proof of the nonequilibrium work relation.Comment: 6 pages, 5 figures. Typos removed, references added. Includes an expanded introductio