Current issue: 54(5)
Under compilation: 55(1)
The Asian chestnut gall wasp (ACGW), Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae) is one of the most important pests in Castanea species worldwide. In 2012, it was found for the first time in Catalonia (Spain) and a year later, in the north of Spain (Cantabria). Today, it is present in 14 Spanish provinces. In search of biological control against the ACGW, several authors have previously found the relationship between the presence of some Fusarium Link species in necrotic galls and wasp mortality due to the production of different types of wall-degrading enzymes and entomopathogenic mycotoxins. The objective of this study was to investigate the mycobiota associated with necrotic galls to find interesting perspectives for biological control of the ACGW. For this purpose, in 2014, 119 necrotic galls of Castanea sativa Miller were plated to isolate and identify the associated fungi. The fungal isolates were identified by the morphology of the fruiting bodies and DNA analyses. From necrotic galls, 7 species of fungi were identified. Of these, we highlight three species of Fusarium Link as well as the presence of Gnomoniopsis smithogilvyi Shuttlew, Liew & Guest due to its toxic capacity. Further studies are required to verify the effectiveness of these fungal species as biocontrol agents against the ACGW.
The susceptibility of Betula pendula Roth and B. pubescens Ehrh. Saplings to stem spot disease caused by Godronia multispora J.W. Groves and Fusarium avenaceum (Fr.) Sacc. was studeied. B. pendula proved to be more susceptible than B. pubescens on all studied soils, especially on peat. G. multispora was more pathogenic than F. avenaceum. Inoculations with G. multispora in the spring and summer induced smaller cancers than in the autumn.
The PDF includes an abstract in Finnish.
Fungal diaspores were caught in Southern Finland (Helsinki, Turku, Jyväskylä, Lappeenranta) and in Northern Finland (Oulu, Ivalo) in 1967—68 on exposed discs of Picea abies (L.) Karst. wood. In the laboratory, the diaspores on the discs developed mycelia which stained the wood. A month after exposure fungi and bacteria were isolated from stained areas.
The number of identified fungal species was relatively high and included fungi of different taxonomic groups. The most common fungi identified were Peniophora gigantea and Trichoderma viride. The most common Agaricaceae obtained were species of Hypholoma. Of the fungi imperfecti, relatively high numbers of not only Trichoderma viride but also of the Alternaria and Fusarium species were isolated. According to the investigation, species of several fungal groups seem to participate in the early stages of the decayed process of spruce.
The PDF includes a summary in Finnish.