Viability of Sirococcus clavigignenti-juglandacearum Conidia on Exoskeletons of Three Coleopteran Species.

Butternut canker, caused by Sirococcus clavigignenti-juglandacearum, is the primary cause of decline of butternut (Juglans cinerea). Conidia of the fungus have been isolated from several insect species. The vector potential of three species of Coleoptera, Astylopsis macula, Eubulus parochus, and Glischrochilus sanguinolentus, was studied during 2001 and 2002.

Leptographium wingfieldii introduced into North America and found associated with exotic Tomicus piniperda and native bark beetles.

Leptographium wingfieldii is a well-known fungal associate of the pine shoot beetle, Tomicus piniperda, in Europe. This fungus is pathogenic to pines and is an important cause of blue-stain in the sapwood of infested trees. Tomicus piniperda was first found in a Christmas tree plantation in Ohio, USA, 1992, but isolation of the fungi associated with these intercepted insects was not attempted.

Effect of Temperature on Thekopsora minima Urediniospores and Uredinia.

Thekopsora minima is a heteroecious rust, with spermogonia and aecia occurring on the needles of hemlock (Tsuga spp.) and uredinia, telia, and basidia occurring on the leaves of ericaceous genera, including species of Rhododendron. The effect of temperature was determined for urediniospore germination, germ tube growth, and infection efficiency on Rhododendron 'White Lights'.

Potential Beetle Vectors of Sirococcus clavigignenti-juglandacearum on Butternut.

To identify potential beetle (Coleoptera) vectors of the butternut canker fungus (Sirococcus clavigignenti-juglandacearum), beetles were collected from butternut (Juglans cinerea) trees and freshly cut logs and branches in Vermont from 1997 through 1999. At least 17 species of beetles, representing eight families, were found to carry conidia of the pathogen. Species most commonly collected and most frequently carrying the fungus were Acoptus suturalis (Curculionidae), Astylopsis macula (Cerambycidae), Eubulus parochus (Curculionidae), and Hyperplatys maculata (Cerambycidae).

Dothistroma Needle Blight, Caused by Dothistroma septospora, of Pinus spp. in Vermont.

Dothistroma needle blight, caused by Dothistroma septospora (teleo-morph Mycosphaerella pini), is a serious foliage disease of pine species throughout the world. In the northeastern United States, the fungus has been reported from Pennsylvania, but not New York, New Jersey, or any of the New England states. It has been reported from the eastern provinces of Canada (Newfoundland, Quebec).