Under the continuous pressure of Dutch elm disease (DED) in Europe, increasing genetic diversity Ulmus minor trees resistant to Ophiostoma novo-ulmi is a priority for species conservation and reintroduction. In this work we screened 121 U. genotypes resistance O. under field experimental conditions. The had been previously obtained through controlled crosses between two moderately (dams) one su...

The European spruce bark beetle (Ips typographus) has become a major forest pest in Finland recent years. is well-known vector of mainly ophiostomatoid fungi causing blue-stain timber and pathogens that have the ability to amplify insect damage. It also vectors other associated organisms, such as phoretic mites. ecology these mites remains poorly understood, including their associations with fu...

Oleoresin flow is an important factor in the resistance of pines to attack by southern pine beetle, Dendroctonus frontalis Zimm., and its associated fungi. Abiotic factors, such as nutrient supply and water relations, have the potential to modify this plant-insect-fungus interaction; however, little is known of the effects of inoculation with beetle-associated fungi on oleoresin flow. We observ...

Conifer bark beetles are often associated with fungal complexes whose components have different ecological roles. Some associated species are nutritionally obligate fungi, serving as nourishment to the larvae, whereas others are pathogenic blue-stain fungi known to be involved in the interaction with host defenses. In this study we characterized the local and systemic defense responses of Scots...

Editor: S. Woodward Summary Five cultivars and two populations of wildtype seedlings of American elm (Ulmus americana), 3 and 4 years old, were examined for differences in their abilities to compartmentalize and resist infection by artificially inoculating with Ophiostoma novo-ulmi. Morphological characteristics of tree defence, often referred to as the compartmentalization of decay in trees mo...

Bark beetles are associated with diverse assemblages of microorganisms, many of which affect their interactions with host plants and natural enemies. We tested how bacterial associates of three bark beetles with various types of host relationships affect growth and reproduction of their symbiotic fungi. Fungi were exposed to volatiles from bacteria in an arena that imposed physical separation b...