The relationship between 'wild' and 'building' isolates of the dry rot fungus Serpula lacrymans.

Molecular and morphological parameters of Serpula lacrymans isolates from various sites in the built environment in Europe and Australia were compared to similar parameters of 'wild' isolates from India, the Sumava Mountains (Czech Republic) and Mount Shasta (USA). The Indian, Czech Republic and all of the building isolates bar one showed identity in both molecular and morphological features. The Australian and the USA isolates (BF-050 and USA'94 respectively) showed specific morphological differences and could be separated on the basis of randomly amplified polymorphic deoxyribonucleic acid polymerase chain reaction (RAPD PCR) with the USA isolate being least closely related to the S. lacrymans type strain of FPRL12C. ITS sequence data revealed two base differences between FPRL12C and BF-050 in the 673 sequenced, nine differences between FPRL12C and USA'94 and 16 differences between USA'94 and the closely related organism Serpula himantioides. The possible evolutionary relationships between the various isolates are discussed along with suggestions for the origin of S. lacrymans as a scourge of the built environment in many temperate areas of the world.

The effects of fungal inoculum arrangement (scale and context) on emergent community development in an agar model system.

Abstract Consequences of initial spatial organisation of model fungal communities upon their spatio-temporal development were investigated. Dynamics of prescribed two- and three-species 'communities' developing on tessellated agar tile model systems were analysed in terms of literal maps, principal component analyses, or as the proportion of species extant within tiles. It was established that for two-species interactions of equal patch size, large-scale (i.e. many constituent tiles) behaviour could be extrapolated from the relevant small-scale (i.e. pairs of tiles) interactions. However, relative patch sizes (scale) of species within tessellations influenced the times taken by individuals to colonise tiles and, hence, temporal behaviour of the system. Outcome of arrangements involving three species of equal patch size and inoculum potential, and prescribed with different mixing patterns, could not be directly extrapolated by reference to the outcome of pair-wise interactions between constituent species. Three-species arrangements attempt to limit assembly of lateral aggregates of individuals (patch size) and hence any effects of tile colonisation times, so as to reveal effects of nearest neighbour context within the complex community. Such arrangements indicate that spatial configuration of inoculum influences community development and reproducibility. They also suggest that spatial distribution of species affects persistence of individuals, which would otherwise be expected to be eliminated from the system. Two-species interactions appeared generally more reproducible than those comprising three species, and the sensitivity of fungal community development to temperature was not solely associated with influence on colony extension rate.

Some aspects of interrelations between fungi and other biota in forest soil.

Interrelations of fungal mycelium with other soil biota are of paramount importance in forestry and soil ecology. Here we present the results of statistical analysis of a comprehensive data set collected in the first (and the only) British fungus sanctuary over a period of four months. The variables studied included a number of soil properties, bacteria, protozoan flagellates, ciliates and amoebae, microbial and plant feeding nematodes, various microarthropods, and two fungal biomarkers--glomalin and ergosterol. One way ANOVA showed that the dynamics of the microbiota studied was influenced by seasonal changes. Superimposed on these changes, however, was variability due to biological interactions and habitat characteristics. Two fungal biomarkers, ergosterol and glomalin, were differently influenced by other biota and abiotic variables. The results indicate that the dynamics of soil fungi is influenced not only by soil microarthropods, but also by those found in forest litter. The overall outcome, therefore, is likely to be very complex and will depend upon specific conditions of any particular ecosystem.