The Chinese species Cryptococcus ulmi Tang & Hao is found to be distantly related to other sampled Cryptococcus species based on both molecular and morphological study. A new felt scale genus, Macroporicoccus Nan & Wu gen. n., is erected therefore for C. ulmi. The new genus differs from other eriococcid genera due to the presence of large simple pores, here referred to as macrodisc pores. The a...

ABSTRACT Twenty-one strains of Botrytis cinerea isolated from 13 species of plants grown in China were compared for pathogenicity on Brassica napus, mycelial growth on potato dextrose agar, and presence of double-stranded (ds)RNA. The results showed that the strain CanBc-1 was severely debilitated in pathogenicity and mycelial growth, compared with the 20 virulent strains. A dsRNA of approximat...

Dutch elm disease fungus Ophiostoma novo-ulmi contains a hydrolase activity which catalyses the resolution of racemic ethyl naproxen to the corresponding acid. The recombinant enzyme has been crystallized by the vapour-diffusion method in two crystal forms. The crystals of the first form belong to space group P2(1)2(1)2, with unit-cell parameters a = 115.9, b = 174.4, c = 62.1 A. The enzyme als...

Dutch elm disease (DED) is a destructive tracheomycosis caused by Ophiostoma novo-ulmi , an ascomycete probably originating in East-Asia that devastating natural populations throughout Europe, North America and Asia. The fungus mainly spread bark beetles complete their life cycle between healthy diseased elms. Recently, it has been highlighted some fungi of the genus Geosmithia which are simila...

We studied the inoculum size effect in Ceratocystis ulmi, the dimorphic fungus that causes Dutch elm disease. In a defined glucose-proline-salts medium, cells develop as budding yeasts when inoculated at > or = 10(6) spores per ml and as mycelia when inoculated at <10(6) spores per ml. The inoculum size effect was not influenced by inoculum spore type, age of the spores, temperature, pH, oxygen...

Invasive tree pathogens threaten forests worldwide, but their effects on streams are poorly understood. Nevertheless, infections that lead to changes in the characteristics of litter inputs may affect stream communities and ecosystem processes. We studied cross-ecosystem derived from Phytophthora cinnamomi, ×alni, Ophiostoma novo-ulmi infection Castanea sativa (chestnut), Alnus lusitanica (alde...