Search results for "honeybee"
showing 10 items of 12 documents
Observations on midgut of Apis mellifera workers (Hymenoptera: Apoidea) under controlled acute exposures to a Bacillus thuringiensis-based biopestici…
2016
International audience; AbstractMorphostructural investigations have been carried out on Apis mellifera workers treated with single controlled acute exposures to a biopesticide containing Bacillus thuringiensis (Bt), to detect midgut changes until 96 h. Our findings show concentration-dependence of these changes, reflecting in different degrees on both mortality and behaviour. In particular, some midgut changes are also found 96 h after treatment. Our results show that the tested product does not affect survival at presumable environmental concentrations, so confirming the lesser toxicity of Bt-based biopesticides compared to other pesticides. However, in the light of the discovered long-te…
Bees increase oilseed rape yield under real field conditions
2018
prod 2018-210 EA GESTAD INRA; International audience; Oilseed rape (OSR, Brassica napus L.) is a common crop found in many European agricultural landscapes. It ispollinated by a wide variety of insects, but the reported contribution of pollinators to yield varies widely betweenstudies (from 0 to 50%). Moreover, such a contribution has seldom been estimated at the field scale in realfarming conditions. We analysed OSR yields in response to insect pollination; over four years, at two differentscales: farm fields and individual plants. We used both empirical and experimental approaches along a gradientof pollinator diversity and abundance. The empirical approach was based on farm surveys (151 …
Honeybees prefer novel insect-pollinated flower shapes over bird-pollinated flower shapes
2019
AbstractPlant–pollinator interactions have a fundamental influence on flower evolution. Flower color signals are frequently tuned to the visual capabilities of important pollinators such as either bees or birds, but far less is known about whether flower shape influences the choices of pollinators. We tested European honeybee Apis mellifera preferences using novel achromatic (gray-scale) images of 12 insect-pollinated and 12 bird-pollinated native Australian flowers in Germany; thus, avoiding influences of color, odor, or prior experience. Independent bees were tested with a number of parameterized images specifically designed to assess preferences for size, shape, brightness, or the number…
Increased survival of honeybees in the laboratory after simultaneous exposure to low doses of pesticides and bacteria
2018
Recent studies of honeybees and bumblebees have examined combinatory effects of different stressors, as insect pollinators are naturally exposed to multiple stressors. At the same time the potential influences of simultaneously occurring agricultural agents on insect pollinator health remain largely unknown. Due to different farming methods, and the drift of applied agents and manure, pollinators are most probably exposed to insecticides but also bacteria from organic fertilizers at the same time. We orally exposed honeybee workers to sub-lethal doses of the insecticide thiacloprid and two strains of the bacterium Enterococcus faecalis, which can occur in manure from farming animals. Our re…
Analysis of Chlorpyrifos in Water, Fruit Juice, and Honeybee Extract by Chemiluminescent Elisa
2008
Abstract The suitability of competitive enzyme-linked immunosorbent assays (ELISAs) with chemiluminescent detection-based immobilized antigen (indirect assay) for rapid and accurate determination of chlorpyrifos in various food matrices was tested. The limit of detection (LOD) values were 1–1.75 ng mL−1, the standard curve midpoint (IC50) was 3.5 ng mL−1, and the assay duration was 1.5 h. Assay application to the analysis of honeybee extract resulted in chlorpyrifos recoveries varying between 62 and 83% in 5–15 ng mL−1 herbicide concentration range.
Quantification of Imidacloprid in Honeybees: Development of a Chemiluminescent ELISA
2010
A Chemiluminescente Enzyme-Linked Immuno-Sorbent Assay (CL-ELISA) for determination and quantification of the fungicide imidacloprid in honeybees was developed in an indirect competitive format. The assay was optimized by determining: the optimal coating conjugate concentration and anti-imidacloprid antiserum dilution, the effect of the incubation time on the competitive step, the tolerance to organic solvents. The IC50 and the limit of detection (LOD) values were 14.8 ng mL-1 and 0.11 ng mL -1, respectively, similar to those of colorimetric ELISA with a calibration range of 0.1 – 2600 ng mL-1. Cross reactivity of some related compounds such as three imidacloprid metabolites, 6-chloro nicot…
Effects of Dietary Supplementation with Honeybee Pollen and Its Supercritical Fluid Extract on Immune Response and Fillet’s Quality of Farmed G…
2022
The awareness of the correlation between administered diet, fish health and products’ quality has led to the increase in the research for innovative and functional feed ingredients. Herein, a plant-derived product rich in bioactive compounds, such as honeybee pollen (HBP), was included as raw (HBP) and as Supercritical Fluid Extracted (SFE) pollen (HBP_SFE) in the diet for gilthead seabream (Sparus aurata). The experiment was carried out on 90 fish with an average body weight of 294.7 ± 12.8 g, divided into five groups, according to the administration of five diets for 30 days: control diet (CTR); two diets containing HBP at 5% (P5) and at 10% (P10) level of inclusion; two diet…
Experience influences elemental and configural perception of certain binary odour mixtures in newborn rabbits.
2011
SUMMARY Elemental and configural olfactory perception allows interaction with the environment from very early in life. To evaluate how newborn rabbits can extract and respond to information from the highly complex chemical surroundings, and how experience acts on this sensory, cognitive and behavioural capability, we ran a study in four steps including a total of eight experiments. We mainly used a binary AB mixture comprising ethyl isobutyrate (component A) and ethyl maltol (component B), previously shown as a bearer of blending properties; in rabbit pups (as in human adults), the mixture elicits a weak configural perception, i.e. the perception of a configural odour different from the odo…
Two novel members of OBP family identified in the honeybee : sexual dimorphism and development studies
1998
International audience
Conceptualization of relative size by honeybees
2014
The ability to process visual information using relational rules allows for decisions independent of the specific physical attributes of individual stimuli. Until recently, the manipulation of relational concepts was considered as a prerogative of large mammalian brains. Here we show that individual free flying honeybees can learn to use size relationship rules to choose either the larger or smaller stimulus as the correct solution in a given context, and subsequently apply the learnt rule to novel colors and shapes providing that there is sufficient input to the long wavelength (green) photoreceptor channel. Our results add a novel, size-based conceptual rule to the set of relational conce…