The aim of this work was to use sexual reproduction to introduce new genotypes into natural populations of Cryphonectria parasitica, the cause of chestnut blight disease. Mating was initiated by painting conidia (which serve as spermatia) onto stromata in cankers initiated in the early spring. The matings yielded perithecia 161 and 180 d after canker initiation. Single-ascospore isolates from these perithecia included cultures with the phenotypes of conidia which had been painted onto the cankers as early as 17 d after canker initiation.

Three new species of Stenella, S. cassiicola, S. eugeniicola and S. rhododendricola, occurring on Cassia fistula, Eugenia heyniana and Rhododendron campanulatum, respectively, are described and illustrated.

Mycological Research is changing for the new millennium. The journal is the major outlet for original mycological research world-wide, reaching the desks of more mycologists than any other in the discipline. Papers in all fields of pure and applied mycology are published, including biochemistry, biocontrol, biodeterioration, biodiversity, biotechnology, ecology, evolution, food spoilage, industrial mycology, genetics, lichens, molecular biology, medical and veterinary mycology, mycorrhizas, mycotoxins, ontogeny, physiology, plant pathology, systematics, ultrastructure, and yeasts. Papers of any length will be considered, as will collections from symposia or workshops (subject to the same review process as other papers). Review articles, which have proved so popular in the past, are encouraged. The journal is available on-line as well as in hard-copy (http://www.journals.cup.org). Advance contents lists are available through the British Mycological Society's home-page(http://www.ulst.ac.uk/faculty/science/bms).

Two new species, Pseudocercosporella arcuata and P. woodfordiana, on Rubus ellipticus and Woodfordia floribunda, respectively, are described and compared with related taxa.

Three grass smuts are recorded from tropical Australia. Sporisorium simile destroys the inflorescence of its host Chionachne in tropical Western Australia. It is distinct from the inflorescence smut Sporisorium reilianum, here recognised for the first time on Chionachne, in Queensland, and from the ovary smut Ustilago polytocae, found on Chionachne in India. Recent use of binomials based on Ustilago holci-sorghi Rivolta for the smut named S. reilianum is discussed and not recommended. Ustilago brunkii is recorded from leaf sheath lesions on Dichanthium in tropical Western Australia. Comparison with a collection of this species from Texas, U.S.A. and with the type species of Jamesdicksonia from India indicates that U. brunkii is best placed in Jamesdicksonia. The identity of its known grass hosts in the U.S.A., Central America and Australia, and their significance in its taxonomy, are discussed.

A mechanism is proposed for the creation of taenia on the capillitium of Trichiales. Polymerization of elater wall material forms spiralling fibrils, releasing water which passes by osmosis into the lumen. This extends the bulbous extremities of Trichia decipiens elaters producing the characteristically tapered tips. The edge of the elater shrinks as water is lost, and is moulded by the fibrils into a system of taenia.

A Variable Number of Tandem Repeats (VNTR) polymorphism has been identified in the ITS1 region of the rDNA in 13 strains belonging to a species of Nodulisporium producing the novel indole diterpene nodulisporic acid. The number of tandem repeats found in these isolates varies from 2, 4 or 5 repetitions, and produces three length morphs in the ITS1 rDNA, spanning a length difference of 217, 308 and 352 nucleotides. Repeated units are rather variable, and they encompass three tandem repeated motifs of 11 nucleotides. In all the individuals, the variants are positioned in the same physical order, following the distribution of the most parsimonious tree. This suggests that this sequence have been enlarged by slipped-strand mispairing occurrences.

An isolate of Coniothyrium minitans did not sporulate on media to which 0·05 mM magnesium was added when κ-carrageenan was used to solidify the medium. Normal conidiation was observed when a technical grade agar or agar-agar was used as the gelling agent. The κ-carrageenan and agars used in this study contained significant amounts of Mg. In the agar media all the Mg present was available to the fungus. By contrast, in the κ-carrageenan gel a large portion of the Mg was bound by the gel and not available. Sporulation of C. minitans was only observed on media containing [ges ]0·17 mM of unbound Mg. The possible role of Mg in the initiation of conidium formation by C. minitans is discussed.

The purification, production and some properties of the intracellular and cell wall associated (1→3)-β-glucanases, (1→6)-β- glucanases and β-glucosidases of Acremonium persicinum have been examined. Anion exchange chromatography revealed the presence of two (1→3)-β-glucanases, one (1→6)-β-glucanase and two β-glucosidases in intracellular extracts of A. persicinum, with further purification by gel filtration chromatography allowing partial characterization of these enzymes. All three intracellular β-glucanases and one of the β-glucosidases appear to be very similar to enzymes found in the extracellular fluid with regard to their molecular masses, hydrolytic action patterns on their substrates, and apparent regulation of syntheses. In contrast, the remaining β-glucosidase appeared to occur only intracellularly and possessed different properties from its extracellular counterpart, most notably being composed of two subunits of 130 and 138 kDa, and its synthesis relatively insensitive to glucose in the medium. Similar anion exchange chromatographic analysis of the cell wall associated enzyme activities extracted by 4 M LiCl revealed the presence of three (1→3)-β-glucanases, one (1→6)-β-glucanase and one β-glucosidase. Except for one (1→3)-β-glucanase all these enzymes appear to be the same as those enzymes found intra- and extracellularly in terms of their action patterns on substrates and their apparent regulation of syntheses. The other apparent cell wall-specific (1→3)-β-glucanase appears to be constitutively produced and is an endo-hydrolase since it displayed no activity toward periodate oxidised laminarin or barley β-glucan. Possible roles for these enzymes are proposed in light of their location, action patterns and apparent regulation of syntheses.

Rhizoctonia solani is a destructive fungal pathogen of many economically important plants all over the world and the causative organism of sheath blight of rice in many tropical countries including Sri Lanka. A repetitive sequence from the genome of R. solani was cloned and characterized with a view to develop a DNA probe and a PCR diagnostic assay for detection of the fungus. The cloned sequence was 1550 bp long and appeared to be interspersed throughout the genome. The cloned sequence hybridized only to R. solani DNA and was sensitive enough to detect 100 pg of R. solani genomic DNA. PCR primers were designed from the cloned sequence and it was possible to develop a PCR assay for the specific detection of the fungal DNA with 10 pg sensitivity.

This number of Mycological Research News features: In this issue; and Novel nitrogen transfer by AM fungi.

Thirteen papers are included in this part, eight utilizing molecular approaches. These concern the detection of tooth fungi, identification of Armillaria tabescens, Armillaria species in Africa, a new genus for Entyloma ossifragi, Anamika species from Asia, a new Hypocrella, the Peronospora attacking sweet basil, and a diagnostic assay for Metarhizium anisopliae var. acridum.

Also included are articles on foraging behaviour of Armillaria rhizomorphs, basidiospore release and dispersal by Amanita muscaria var. alba, metabolites of Penicillium albocoremium, interactions between rock-inhabiting fungi and algae from lichens, and root colonization by Monosporascus cannonballus.

The following new scientific names are introduced: Gjaerumiaceae fam. nov.; Gjaerumia gen. nov.; Anamika angustilamellata, and Hypocrella macrostroma spp. nov.; and A. lactariolens (syn. Alnicola lactariolens), and G. ossifragi (syn. Entyloma ossifragi) combs. nov.