Commercial apple production relies on managed honey bees for pollination, and on intensive management for pest control. Previous studies revealed the detrimental effects of these factors on wild bee diversity in agroecosystems, and the pollination services they provide. However, the extent to which honey bee dominance and management interact under field-realistic conditions to shape wild communities has never been investigated. We measured the species richness and functional and phylogenetic diversity of wild bees associated with apple blossoms, in 46 organic and non-organic orchards, and along a climatic gradient across Western Europe and Morocco. Our results consistently show a strong and negative association between honey bee dominance and all diversity indices, regardless of local practices and surrounding landscape cover. Collectively, we show that wild bee diversity decreases with increasing honey bee density, with alternative management practices (i.e., organic) having no significant influence on wild bee communities in commercial apple orchards.

The influence of phenolic compounds on the enzymatic hydrolysis of cellulose was studied in depth using spectrophotometric techniques, adsorption analysis and Scanning Electron Microscopy (SEM). In this paper, both possible interactions between phenolic compounds and the enzyme or the substrate were investigated with the use of various phenolic compounds, cellulase from T. reesei, and Avicel. Three classes of phenolic compounds have been identified, based on their effect on the hydrolysis of cellulose: inhibitors (quercetin, kaempferol, cinnamic acid, luteolin, ellagic acid), non-inhibitors, and activators (ferulic acid, syringic acid, sinapic acid, vannilic acid). Secondly, since various structures of phenolic compounds were investigated, it was deduced that an -OCH3 group was necessary for the activating effect. Finally, based on the adsorption spectra and SEM images, a different way of adsorption (either on the enzyme or on the substrate) was noticed, depending if a phenolic compound was an inhibitor or an activator.