We report the cloning and sequencing of a DNA fragment encoding a putative C2H2 zinc finger protein from Aspergillus nidulans. The gene was isolated by complementation cloning of a salt sensitive phenotype of the A. nidulans sltA1 mutant. A 3·8 kb PstI fragment that restored wild type salt tolerance contained one large open reading frame of 2202 bp. The predicted protein (StzA) from this reading frame comprises 698 amino acids and has three Zinc fingers along with a putative transcriptional activation domain rich in acidic amino acids. The corresponding sequence from a sltA1 mutant contains a premature STOP codon resulting in loss of the putative transcriptional activator in the C-terminal region. The Zinc fingers show conserved motifs with a number of transcription factors including CreA from A. nidulans and the human Wilm's tumour susceptibility protein WT-1.

A somatic incompatibility system was demonstrated in Rosellinia necatrix (anamorph Dematophora necatrix) through barrage formation in pairings among mass fungal isolates from infected avocado trees in commercial orchards in southern Spain, as well as among single ascospore isolates derived from perithecia formed in infected roots. Results revealed the occurrence of high diversity in somatic incompatibility in the R. necatrix population in the study. The occurrence of R. necatrix perithecia in naturally infected avocado roots in the field suggests that such a diversity might originate from sexual reproduction. However, the possibility that other parasexual mechanisms demonstrated in this fungus may contribute to the genetic diversity can not be discounted.

A new pyrenomycete, Monosporascus ibericus sp. nov., isolated as an endophyte from roots and stems of three plant species growing on sand flats and salt marshes in the Ebro Delta (Spain), is described. The main characteristic of this fungus is the presence of a higher number of ascospores per ascus (up to six), compared to the other species of the genus: M. cannonballus, M. eutypoides, and M. monosporus. M. ibericus produces a cleistothecial ascomata with a tomentose peridium and lacks an anamorph. In addition to the morphological data, the comparative analysis of the ITS-region sequences of M. ibericus and the other Monosporascus spp., has supported the recognition of the new species. A phylogenetic study based on the sequences of the 18S rDNA did not allow us to assess clearly the taxonomic position of the genus Monosporascus, although the results indicated the genus might have affinities to the Xylariales rather than to the Sordariales.

Anzia electra sp. nov. is described and illustrated from Baltic amber dating back approx. 40 Myr. The diagnostic features of the fossilised species include the small, narrow lobed foliose thallus, two-layered medulla, lack of chondroidal axis, moniliform spongiostratum, and rhizines born singly at the margins of spongiostratum cushions. The fossil species demonstrates that all distinguishing features in the thallus morphology of Anzia sect. Anzia have remained stable for tens of millions of years. Hence the divergence of anzioid lichens must have occurred in the distant past, most probably before the Tertiary. The fossil also provides the first hard evidence that the disjunct-Laurasian distributions of some modern lichens represent relicts of a formerly wider range. The close similarity of the fossil to extant species in East Asia and eastern North America suggests that the present range of Anzia sect. Anzia is highly relict.

Paraphaeosphaeria barrii, a new species of the genus found on Agavaceae, is described from leaves of Yucca schidigera collected in Baja California, Mexico. The Coniothyrium anamorph is briefly described from cultured ascospores. This species was found to be most closely related to P. conglomerata, P. filamentosa, and P. quadriseptata all of which are from Agavaceae, produce 3 or 4 septate ascospores and pigmented, non-septate conidia from holoblastic, percurrently proliferating conidiogenous cells.

The entomopathogenic fungus Alternaria alternata grew equally well on potato dextrose agar (PDA) and also on potato extract agar (PEA). The latter was excellent for sporulation. The fungus grew at a wide temperature range of 15–35 °C with an optimum at 25 °. On PDA sporulation was much reduced as compared to that on PEA. The spores of the fungus germinated only at 100% relative humidity (rh). Darkness significantly increased the germination percentages in the early stages of germination at all temperatures tested. Differences in germination percentages between light and dark conditions were mostly levelled 24 h post incubation. The germ tubes formed distinct appressoria, both on glass slides and on the aphid host Anuraphis nerii, on which appressoria were formed on all parts of the insect bodies, even on the hardest ones, such as the head and thorax. Most appressoria were single globose and formed terminally on hyphal branches. Few were subapical and still fewer compound and multilobed. Detachment of appressoria from their original position revealed an exceedingly smoothened appression area, around which a mucilagenous material was secreted, apparently cementing them onto the host epicuticle. Optimum temperature for appressorium formation was 20–25 °. At these temperatures more than 80% of the emerging germ tubes formed appressoria. The factors affecting spore germination and appressorium formation are discussed in relation to the prevailing environmental conditions in the mediterranean area as well as their role in influencing the spread and activities of the pathogen and the infection of aphids under field conditions.

This study aimed to test whether fungal community on moose (Alces alces) dung is affected by habitat. We used dung of homogenous origin, composition, and age. Dung was placed in three different habitats in north-eastern Sweden, and was checked again after 35–36 d. Of the 26 species of fungi found, 12 were new to the region, 17 had never been observed on moose dung, and two were not previously described. We found a significant difference in species composition between the habitats, with a low number of species in the spruce forest and about a threefold increase in the pine forest and the open mire. Species diversity was negatively associated with degree of insect attack. This suggests that insects feeding either on the dung or the fungi (spores, mycelia) may be an important factor explaining the observed pattern. In order to test this hypothesis we need to run experiments excluding insects.

The present investigation deals with the main factors involved in early infection of nematode eggs by fungal parasites. We studied the effect of hydrophobicity on appressorium formation by germlings of Pochonia rubescens (syn. Verticillium suchlasporium), P. chlamydosporia (syn. V. chlamydosporium) and Lecanicillium lecanii (syn. V. lecanii). Appressoria were frequently formed on hydrophobic surfaces such as polyvinyl chloride or polystyrene and were infrequently formed on hydrophilic materials such as glass or aluminium. Infected eggs probed with the FITC-labelled lectin Concanavalin-A showed intense labelling corresponding to appressoria formed by fungal parasites on the eggshell surface. Proteolytic activity was found in extracts from conidia and germlings of fungal parasites (especially P. chlamydosporia) in the absence of nematode eggs. Addition of the serine proteinase inhibitors phenylmetylsulphonyl fluoride (PMSF) or diisopropyl fluorophosphonate (DFP) to the extracts reduced their proteolytic activity. PMSF was the most effective inhibitor. Zymography also revealed proteolytic activity in extracts from the three fungi tested. This activity mostly corresponded to bands of Rf's of substrate degradation similar to that of purified main protease (P32) from P. rubescens. Other bands with molecular weight higher than P32 (low Rf) were found especially for P. chlamydosporia extracts. For L. lecanii only bands of low Rf were found. Serum anti-P32 partially inhibited proteolytic activity of extracts from conidia and germlings. Application of PMSF and DFP to the inoculum, reduced egg penetration for the three species studied. PMSF caused the highest reduction in eggs infected by L. lecanii, while DFP significantly reduced egg infection by both P. chlamydosporia and L. lecanii. Our results therefore show hydrophobicity, appresorium formation and protease production as factors involved in early parasitism of nematode eggs.

Anamika gen. nov. is described from southern India with one species, A. indica sp. nov. The genus is characterized by spores with a strongly cavernous ornamentation due to cavernae in the epitunica (perispore), and the possession of cheilo-, pleuro-, and caulocystidia. It seems to be associated with Hopea species (Dipterocarpaceae). Molecular data suggest a close relationship to Hebeloma and Naucoria, but indicate that it represents an independent line of evolution.