Pollinosis to birch pollen is a common type I allergy in the Northern Hemisphere. Moreover, birch pollen-allergic individuals sensitized to the major birch pollen allergen Bet v 1 frequently develop allergic reactions to stone fruits, hazelnuts, and certain vegetables due to immunological cross-reactivity. The major T cell epitope Bet v 1(142-153) plays an important role in cross-reactivity bet...

The aim of this study was to examine the effects of elevated carbon dioxide [CO2] and ozone [O3] and their interaction on wood chemistry and anatomy of five clones of 3-yearold trembling aspen (Populus tremuloides Michx.). Wood chemistry was studied also on paper birch (Betula papyrifera Marsh.) and sugar maple (Acer saccharum Marsh.) seedling-origin saplings of the same age. Material for the s...

Abstract Tree-derived dissolved organic matter (DOM) comprises a significant carbon flux within forested watersheds. Few studies have assessed the optical properties of tree-derived DOM. To increase understanding factors controlling DOM quality, we measured properties, (DOC) and calcium concentrations in throughfall stemflow for 17 individual rain events during summer fall temperate deciduous f...

Climate warming increases the risk of insect defoliation in boreal forests. Losses in photosynthetically active surfaces cause reduction in net primary productivity and often compromise carbon reserves of trees. The concurrent effects of climate change and removal of foliage on root growth responses and carbohydrate dynamics are poorly understood, especially in tree seedlings. We investigated i...

Latitudinal patterns in herbivory, i.e. variations in plant losses to animals with latitude, are generally explained by temperature gradients. However, earlier studies suggest that geographical variation in abundance and diversity of gall-makers may be driven by precipitation rather than by temperature. To test the above hypothesis, we examined communities of eriophyoid mites (Acari: Eriophyoid...

One-year-old jack pine (Pinus banksiana Lamb.) and current-year white birch (Betula papyrifera Marsh.) seedlings were grown in ambient (360 ppm) or twice ambient (720 ppm) atmospheric CO2 concentration ([CO2]) and at three soil temperatures (Tsoil = 7, 17 and 27 degrees C initially, increased to 10, 20 and 30 degrees C two months later, respectively) in a greenhouse for 4 months. In situ foliar...

Spectral reflectance and chlorophyll fluorescence are rapid non-invasive methods that can be used to quantify plant stress. Because variation in ambient light (e.g., diurnal patterns of solar radiation) may have a confounding effect on these measurements, branches are often excised in the field and then measured under controlled conditions in the laboratory. We studied four temperate tree speci...

The role of common mycorrhizal networks (CMNs) in postfire boreal forest successional trajectories is unknown. We investigated this issue by sampling a 50-m by 40-m area of naturally regenerating black spruce (Picea mariana), trembling aspen (Populus tremuloides), and paper birch (Betula papyrifera) seedlings at various distances from alder (Alnus viridis subsp. crispa), a nitrogen-fixing shrub...

The pattern of food allergy in adults is different from that of children in various aspects. The typical foods involved in infants are milk, egg, peanut and probably tree nuts, whereas in older children and adults fruits and nuts are the most frequent allergenic foods. In addition, allergy to vegetables can occur. Allergy to milk and egg largely disappears at young age, but can still be present...

Handling Editor: Matthew Heard Abstract 1. How much a plant is attacked by insect herbivores likely depends on its apparency and ability to produce defensive traits, which may be modified by neighbouring plants and abiotic conditions. Yet, how much the direct and trait-mediated effects of neighbours on herbivory is modified by abiotic factors is still unknown. 2. By using a tree diversity exper...