Publications

effects of flowering plant's patch size on species composition of pollinator communities, foraging strategies, and resource partitioning in bumblebees (hymenoptera: apidae).	in 4 common middle-european mainly bumblebee-pollinated plant species (impatiens glandulifera, echium vulgare, aconitum napellus, symphytum officinale) the influence of patch size on species composition of the pollinator community was studied. short-tongued species were most dominant in large patches, while small patches were frequented by middle- and long-tongued bumblebees. this phenomenon was extremely obvious in symphytum officinale and aconitum napellus, where short-tongued species had bitt ...	1989	28312186
the responses of cytochrome redox state and energy metabolism to dehydration support a role for cytoplasmic viscosity in desiccation tolerance	to characterize the depression of metabolism in anhydrobiotes, the redox state of cytochromes and energy metabolism were studied during dehydration of soaked cowpea (vigna unguiculata) cotyledons and pollens of typha latifolia and impatiens glandulifera. between water contents (wc) of 1.0 and 0.6 g h2o/g dry weight (g/g), viscosity as measured by electron spin resonance spectroscopy increased from 0.15 to 0.27 poise. this initial water loss was accompanied by a 50% decrease in respiration rates, ...	1998	9847099
quantitative determination of naphthoquinones of impatiens species.	a convenient and reliable reversed phase-hplc method has been developed and validated for the quantitative determination of naphthoquinones present in the aerial parts of impatiens glandulifera (balsaminaceae) during two growing seasons (may to august 1998 and june to october 1999). maximal content (0.8-1.1%) of 2-hydroxy-1,4-naphthoquinone and its 2-methylated derivative was observed in flowers collected between july and august. the procedure was applied to compare the pigment content in three ...	2001	11705027
extension growth of impatiens glandulifera at low irradiance: importance of nitrate and potassium accumulation.	the summer annual impatiens glandulifera can reach 3 m in height within deciduous woodland. the primary objective was to determine if no(3)(-) accumulation, and hence its osmotic effect, is an important physiological mechanism allowing impatiens to achieve substantial height under low irradiance.	2005	15644384
the impact of an alien plant on a native plant-pollinator network: an experimental approach.	studies of pairwise interactions have shown that an alien plant can affect the pollination of a native plant, this effect being mediated by shared pollinators. here we use a manipulative field experiment, to investigate the impact of the alien plant impatiens glandulifera on an entire community of coflowering native plants. visitation and pollen transport networks were constructed to compare replicated i. glandulifera invaded and i. glandulifera removal plots. invaded plots had significantly hig ...	2007	17542933
effects of the compounds 2-methoxynaphthoquinone, 2-propoxynaphthoquinone, and 2-isopropoxynaphthoquinone on ecdysone 20-monooxygenase activity.	the effects of the natural compound 2-methoxy-1,4-naphthoquinone, isolated from the leaves of impatiens glandulifera and the synthetic compounds 2-propoxy-1,4-naphthoquinone and 2-isopropoxy-1,4-naphthoquinone on ecdysone 20-monooxygenase (e-20-m) activity were examined in three insect species. homogenates of wandering stage third instar larvae of drosophila melanogaster, or abdomens from adult female aedes aegypti, or fat body or midgut from fifth instar larvae of manduca sexta were incubated w ...	2007	17694563
impacts of alien invasive plants on soil nutrients are correlated with initial site conditions in nw europe.	alien invasive plants are capable of modifying ecosystem function. however, it is difficult to make generalisations because impacts often appear to be species- and site-specific. in this study, we examined the impacts of seven highly invasive plant species in nw europe (fallopia japonica, heracleum mantegazzianum, impatiens glandulifera, prunus serotina, rosa rugosa, senecio inaequidens, solidago gigantea) on nutrient pools in the topsoil and the standing biomass. we tested if the impacts follow ...	2008	18491146
a retrospective analysis of pollen host plant use by stable and declining bumble bee species.	understanding population declines has been the objective of a wide range of ecological studies. when species have become rare such studies are complicated because particular behavior or life history traits may be the cause but also the result of the decline of a species. we approached this problem by studying species' characteristics on specimens that were collected before the onset of their decline and preserved in natural history museums. in northwestern europe, some bumble bee species decline ...	2008	18705369
invasive plant integration into native plant-pollinator networks across europe.	the structure of plant-pollinator networks has been claimed to be resilient to changes in species composition due to the weak degree of dependence among mutualistic partners. however, detailed empirical investigations of the consequences of introducing an alien plant species into mutualistic networks are lacking. we present the first cross-european analysis by using a standardized protocol to assess the degree to which a particular alien plant species (i.e. carpobrotus affine acinaciformis, impa ...	2009	19692403
seedling traits, plasticity and local differentiation as strategies of invasive species of impatiens in central europe.	background and aimsinvasiveness of some alien plants is associated with their traits, plastic responses to environmental conditions and interpopulation differentiation. to obtain insights into the role of these processes in contributing to variation in performance, we compared congeneric species of impatiens (balsaminaceae) with different origin and invasion status that occur in central europe.methodsnative i. noli-tangere and three alien species (highly invasive i. glandulifera, less invasive i ...	2012	22247125
interference of field evidence, morphology, and dna analyses of three related lysiphlebus aphid parasitoids (hymenoptera: braconidae: aphidiinae).	this study provides evidence on integrating the morphological, field, and laboratory data, and application of the cytochrome oxidase subunit i (coi) barcoding gene to the three asexual or sexual lysiphlebus spp., i.e., lysiphlebus cardui (marshall), lysiphlebus confusus tremblay and eady and lysiphlebus fabarum (marshall) (hymenoptera: braconidae: aphidiinae). new aphid- invasive plant association, aphis fabae scopoli (hemipreta: aphididae) on impatiens glandulifera royle, has been used in the s ...	2014	25399432
using dna metabarcoding to identify the floral composition of honey: a new tool for investigating honey bee foraging preferences.	identifying the floral composition of honey provides a method for investigating the plants that honey bees visit. we compared melissopalynology, where pollen grains retrieved from honey are identified morphologically, with a dna metabarcoding approach using the rbcl dna barcode marker and 454-pyrosequencing. we compared nine honeys supplied by beekeepers in the uk. dna metabarcoding and melissopalynology were able to detect the most abundant floral components of honey. there was 92% corresponden ...	2015	26308362