Whereas most of the research on phloem loading is performed on herbaceous plants, less is known about phloem loading strategies in trees. In this study, the phloem loading mechanisms of Quercus robur and Fraxinus excelsior were analysed. The following features were examined: the minor vein structure, the sugar concentrations in phloem sap by the laser-aphid-stylet technique, the distribution of...

specific features of the structure of the ground litter invertebrate community in forest belt ecosystems in the ukrainian steppe zone have been considered. for 14 years invertebrate fauna of the litter of 176 forest belt sites with different composition has been studied with the aid of soil traps. the main characteristics of litter invertebrate communities (total population, a number of species...

Abstract Key message Paternity analyses show that effective pollination of ash ( Fraxinus excelsior L.) in a seed orchard and floodplain forest affected by dieback is more likely to be facilitated healthier males. Thereby, natural selection can have positive effect on the health future generations. Context Ongoing increasing fragmentation populations may result reduced pollen flow, which reduce...

The phenolic composition of heartwood extracts from Fraxinus excelsior L. and F. americana L., both before and after toasting in cooperage, was studied using LC-DAD/ESI-MS/MS. Low-molecular weight (LMW) phenolic compounds, secoiridoids, phenylethanoid glycosides, dilignols and oligolignols compounds were detected, and 48 were identified, or tentatively characterized, on the basis of their reten...

We assessed the effects of ambient tropospheric ozone on annual tree-ring growth, delta(13)C in the rings, leaf gas exchange and visible injury in three ozone-sensitive woody plant species in southern Switzerland. Seedlings of Populus nigra L., Viburnum lantana L. and Fraxinus excelsior L. were exposed to charcoal-filtered air (CF) and non-filtered air (NF) in open-top chambers, and to ambient ...