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Commercial lowbush blueberry (Vaccinium angustifolium Ait.) and cranberry (Vaccinium macrocarpon Ait.) crops benefit from the presence of honey bee (Apis mellifera L.) for pollination. Unfortunately, beekeepers are observing negative impacts of pollination services on honey bee colonies. In this study, we investigated three beekeeping management strategies (MS) and measured their impact on honey bee colony health and development. Experimental groups (five colonies/MS) were: A) Control farmland honey producing MS (control MS); B) Blueberry pollination MS (blueberry MS); C) Cranberry pollination MS (cranberry MS) and D) Double pollination MS, blueberry followed by cranberry (double MS). Our goals were to 1) compare floral abundance and attractiveness of foraging areas to honey bees between apiaries using a Geographic Information System, and 2) compare honey bee colony health status and population development between MS during a complete beekeeping season. Our results show significantly lower floral abundance and honey bee attractiveness of foraging areas during cranberry pollination compared to the other environments. The blueberry pollination site seemed to significantly reduce brood population in the colonies who provided those services (blueberry MS and double MS). The cranberry pollination site seemed to significantly reduce colony weight gain (cranberry MS and double MS) and induce a significantly higher winter mortality rate (cranberry MS). We also measured significantly higher levels of Black queen cell virus and Sacbrood virus in the MS providing cranberry pollination (cranberry MS and double MS). [ABSTRACT FROM AUTHOR]

The biocontrol of the honey bee ectoparasite Varroa destructor is an underexploited but promising avenue that would benefit from being integrated in a Varroa management program. Our study aimed to investigate the potential of the predatory mite Stratiolaelaps scimitus to control Varroa infestations in honey bees. Tests on safety and predation were carried out to: (1) assess the risk of predation of the honey bee brood by S. scimitus under laboratory conditions and within the colony, and (2) evaluate the predation potential of S. scimitus on phoretic Varroa mites. Under laboratory conditions, S. scimitus was able to feed upon free Varroa mites, but also attacked every unprotected honey bee brood stages with a strong preference for bee eggs. When introduced inside colonies, however, S. scimitus does not have negative effects on the survival of the bee brood. Moreover, observations made in the laboratory revealed that S. scimitus does not attack Varroa mites when they are attached to the body of bees. However, all Varroa mites that had naturally fallen from the bees were predated upon by S. scimitus and died in less than 24h. This study provides evidence that S. scimitus does not represent a significant threat to the bee brood, but also suggests that its effect in Varroa control will probably be limited as it does not attack phoretic Varroa mites. Our results represent a first step in assessing the potential of S. scimitus to control V. destructor and provide novel information about the predator’s behavior inside the honey bee colony. [ABSTRACT FROM AUTHOR]

In Canada, there is a growing need for additional honey bee colonies to satisfy the demand for pollination services and compensate for high winter colony mortality. The objective of our study was to compare methodologies that would be both better structured and adapted to producing new colonies in today’s beekeeping industry. Efficacy of three colony production techniques was compared at the Deschambault Research Center for Animal Sciences, Québec: package bees, one brood frame, two brood frames. Experimental colonies were monitored from July 2014 to June 2015, and several parameters were measured to evaluate their strength and the presence of pathogens. Results showed no statistical difference in colony strength between methods. However, making nuclei from one brood frame offered the greatest multiplication potential and the most advantageous economically. This study also confirmed that nuclei production reduces swarming and varroa infestation levels in mother colonies. [ABSTRACT FROM AUTHOR]

Evaluation of the performance of a plant-herbivore system as a whole is difficult due to the lack of fitness parameters that can be applied to both components. The individual use of traditional measures of performance (e.g., rm, biomass) can provide useful, but incomplete information on the performance of insect herbivores and seldom incorporates plant performance. We propose the use of the net generational productivity ( NGP) to evaluate the fitness of the herbivore, which can then be compared directly with the performance of the plant in biomass units, to obtain the food-web performance ratio (φH/P). We compared three biotypes of the potato aphid, Macrosiphum euphorbiae Thomas ( Hemiptera: Aphididae), when raised on three different host plants: potato ( Solanum tuberosum L. cv. Norland) and two bell peppers ( Capsicum annuum L. cv. Fascinato and cv. Crosby) (all Solanaceae) at temperatures ranging from 8 to 36 °C. The temperature profiles of the potato aphid biotypes suggest that this aphid is better suited to temperate climates, and its performance generally depends on the particular host-plant/biotype association. Plant growth performance showed that potato has a lower thermal tolerance, but has a faster growth rate than bell peppers, especially in the range of 16-24 °C. Temperature variation in the φH/P ratio shows that aphids have a greater performance than plants, especially at lower temperatures, at which they can accumulate biomass up to 148 times faster. Because of the aphid's biological inability to withstand long exposures to temperatures above 28 °C, plants have a slight advantage over aphids. Nonetheless, as the performance of plants is extremely reduced at high temperatures, this advantage cannot withstand long-term exposures to extreme temperatures. This is the first attempt to obtain a parameter capable of determining the climatic profile and performance of a food web in an inclusive yet simple manner. [ABSTRACT FROM AUTHOR]

Discusses the fleshing out of gender by drawing connections between the experience of pain and the experience of womanhood. Constitution of women through her effacement; Inscription of gender on the body; Analysis of effacement in terms of an embodied sense of being gutted out or made immaterial; View that gender is performed through inscriptions on the body.

The article focuses on rescuing of Utopian thinking and writing from its neglect by critics of managerialism. It mentions development of Utopian thinking, identifying a number of common strands running through the fabric of utopianism and possibilities for the development of Utopian thinking by critical organizational theorists. It mentions creative construction of Utopias can make a contribution to critical thinking.

The paper is an attempt to engage with our contemplations of violence and the failure of familiar explanations to capture these contemplations. We begin our explorations of these familiar accounts by examining contemporary debates on media violence but find these problematic. By reducing media violence to mere spectacle or, on the contrary, by seeing such violence as desensitising and destructive, the various positions in the debates deprive violence of meaning and fail to address our fascination with violence. Other explanations that seek to attach meaning or utility to violence, be it economic, symbolic or moral, equally fail to convince. There is always an excess that transcends these explanations, an excess that is ill-captured by the notion of `gratuitous violence' often deployed to condemn violence that does not make sense. Further- more, the various accounts of violence we review tend to consider violence only in terms of its victims and perpetrators rather than the (fortunately) more common position of the observer. In the remaining of the paper, we try to say something about the sense of violence without investing it with deterministic or moralistic implications. This leads us to re-interpret the notion of desensitisation; for the observer, desensitisation indexes a lack of sensation of violence. This lack of sensation, our inability as observers to sense and make sense of violence, we argue, brings about moral questioning and acuity rather than moral indifference. [ABSTRACT FROM AUTHOR]

The article examines the deployment of "professional" discourses in occupational domains not traditionally associated with the professions. It first proposes to analyze professionalism as a disciplinary logic which inscribes "autonomous" professional practice within a network of accountability and governs professional conduct at a distance. It has been argued that professional labor is autonomous labor where the conditions of autonomy have already been inscribed in particular forms of conduct embodied in the notion of "professional competence." The article suggests that the appeal to the discursive resources of professionalism in new occupational domains potentially acts as a disciplinary mechanism that serves to profess "appropriate" work identities and conducts. The extension of the disciplinary logic of professionalism is illustrated with the turn to competencies to regulate managerial work in Teamco, a large privatized service company. However, the final section of the paper cautions against a deterministic analysis of the disciplinary logic of professionalism in regulating employees' conduct, and suggests that the constructed and contestable nature of professionalism makes it an inevitably imperfect form of government.

Bumble bee communities are strongly disrupted worldwide through the population decline of many species; a phenomenon that has been generally attributed to landscape modification, pesticide use, pathogens, and climate change. The mechanisms by which these causes act on bumble bee colonies are, however, likely to be complex and to involve many levels of organization spanning from the community down to the least understood individual level. Here, we assessed how the morphology, weight and foraging behavior of individual workers are affected by their surrounding landscape. We hypothesized that colonies established in landscapes showing high cover of intensive crops and low cover of flowering crops, as well as low amounts of local floral resources, would produce smaller workers, which would perform fewer foraging trips and collect pollen loads less constant in species composition. We tested these predictions with 80 colonies of commercially reared Bombus impatiens Cresson placed in 20 landscapes spanning a gradient of agricultural intensification in southern Québec, Canada. We estimated weekly rate at which workers entered and exited colonies and captured eight workers per colony over a period of 14 weeks during the spring and summer of 2016. Captured workers had their wing, thorax, head, tibia, and dry weight measured, as well as their pollen load extracted and identified to the lowest possible taxonomic level. We did not detect any effect of landscape habitat composition on worker morphology or body weight, but found that foraging activity decreased with intensive crops. Moreover, higher diversity of local floral resources led to lower pollen constancy in intensively cultivated landscapes. Finally, we found a negative correlation between the size of workers and the diversity of their pollen load. Our results provide additional evidence that conservation actions regarding pollinators in arable landscapes should be made at the landscape rather than at the farm level. [ABSTRACT FROM AUTHOR]

Climate change has facilitated the introduction, establishment, and movement of invasive species in northern regions, enabling the colonization of previously unsuitable areas. While the responses of insects to these changes have been increasingly studied, our understanding of how such alterations impact trophic interactions still requires further research to make reliable predictions about the spread of diseases in a warming world. Phytoplasmas, a group of obligate parasitic unculturable Mollicutes, primarily rely on leafhoppers (Hemiptera: Cicadellidae) for transmission, spread, and survival. Phytoplasmas are associated with over 600 diseases affecting more than 1,000 plant species, including berries, grapevines, and other small fruits. In North America, diseases such as grapevine yellows, blueberry stunt, and strawberry green petal diseases have been linked to phytoplasma strains transmitted by known leafhopper species. However, the number of phytoplasma diseases has significantly increased in North America over the past decade, suggesting the presence of unidentified vectors or an abundance of leafhopper vectors. This short review provides an overview of the current knowledge on leafhoppers as vectors of phytoplasmas to berries, focusing on the last decade's research in Canada. This paper also explores the potential implications of climate change on this pathosystem, including the anticipated range expansion of leafhopper species, changes in phytoplasma acquisition and transmission, and the risk of new leafhopper-transmitted plant-pathogen introductions through the arrival of new leafhopper species. [ABSTRACT FROM AUTHOR]

Abstract A 2-year study was conducted in the main cranberry (Vaccinium macrocarpon Aiton) growing region of Québec to determine the biodiversity of lepidopteran pests and their parasitoids, which may differ in organic and conventional integrated pest management (IPM) systems. We also aimed to compare densities and parasitism on five caterpillar pest species of primary economic importance: Macaria sulphurea (Packard), Macaria brunneata (Thunberg) , Xylena nupera (Lintner), Rhopobota naevana (Hübner) and Sparganothis sulfureana (Clemens), which accounted for more than 80% of the pest community each year. The lepidopteran pest communities clearly varied between the two pest management systems, suggesting efficacy differences among them. Rhopobota naevana was dominant on organic farms, whereas conventional farms had greater pest richness and evenness, with M. sulphurea , M. brunneata and X. nupera being the most abundant. Based on laboratory rearing of field collected caterpillars, the parasitoid community was composed of 25 species or taxa (22 from primary pests) and communities were not significantly different between the two farming regimes. The most common species belonged to the braconid genera Aleiodes , Meteorus , Microplitis , Oncophanes ; ichneumonids Hyposoter , Exetastes , Phytodietus ; and tachinids Campylocheta , Nemorilla. Of the five primary pests, X. nupera was the most parasitized, while no parasitoids were reared from M. brunneata. Annual parasitism rate of the primary pests ranged 20–40% and data showed that it was explainable by host availability rather than farming system. [ABSTRACT FROM AUTHOR]

While evidence of insect pollinator declines accumulates, little is known about the pollinator communities that are most vulnerable to population fluctuations and may require conservation actions. Among the main reasons for this lack of knowledge about the status and trends of native pollinators are the time, cost, and expertise required to collect and identify wild insect pollinators (bees, more specifically). Here, we discuss how leveraging the complementarity of community science and taxonomist expertise can help overcome these challenges and provide perspective and insights from launching the large‐scale monitoring program Abeilles citoyennes. The overall objective of this community science project is to monitor wild bee (Apoidea) and hover fly (Syrphidae) diversity in the province of Quebec, Canada, and study the effects of landscape composition on their communities. From 2019 to 2021, 131 volunteers collected insects at 161 sites across the province. A total of 13,558 bees and 2,486 hover flies were collected and identified to species. The project protocol and potential data uses are presented, along with a discussion of the benefits and challenges of using an expert‐assisted community science approach for pollinator monitoring and opportunities for improvement. [ABSTRACT FROM AUTHOR]

Global declines in wild and managed bee populations represent a major concern for the agricultural industry. Such declines result, in part, from the loss of natural and semi-natural habitats in and around agricultural ecosystems. However, remaining forest patches in heavily modified landscapes represent nesting habitats that may be crucial to preserving wild bees and their services. Because wild bees are the main pollinators of fruit crops, preserving potential nesting habitats might be particularly important for the crops' yield and profitability. Here, we assessed whether the abundance and richness of visiting wild bees in blueberry crops relates to the amount of surrounding forest cover and if so, whether those relationships varied with spatial scale. Specifically, we sampled wild bee communities in 18 blueberry fields during the blooming period in Montérégie, Quebec, Canada, where sampling consisted of pan trap triplets and direct observation of flower visitors on blueberry bushes. Then, we quantified the proportion of forest in radii of 0.5 km, 1 km, and 2 km around each field. Wild bee abundance was positively related to the proportion of forest habitat surrounding the crop field, but the relationship for wild bee richness was less clear. Moreover, these relationships were strongest at 1 and 2 km radii of measured land cover. Overall, pollinator diversity was highest when at least 30% of the surrounding landscape consisted of forest patches, representing a total area of at least 1 km2. Our results suggest that preserving large habitat patches in agricultural landscapes can help prevent further decline in wild bee diversity while maximizing pollination services to fruit crops. [ABSTRACT FROM AUTHOR]

1. Food web interactions are complex and can respond to environmental changes in unpredictable ways that do not necessarily equate to the individual responses of each of the components of the food web. 2. Biomass can be used to evaluate the productivity of the three individual trophic levels, in the form of the Net Generational Productivity ( NGP) and the performance of the entire food web with the newly developed tri-trophic food web performance ratio (ϕ3t). 3. These parameters were used to evaluate the performance of nine plant-based tri-trophic food webs composed of: potato, Solanum tuberosum L. and two cultivars of bell pepper Capsicum annuum L; three biotypes of the aphid Macrosiphum euphorbiae Thomas ( Hemiptera: Aphididae) and the parasitoid wasp Aphidius ervi ( Haliday) ( Hymenoptera: Braconidae). 4. The NGP showed that the thermal window for biomass productivity for each trophic level is different and is reduced by approximately 4 ° C with respect to the inferior level. Aphidius ervi had the smallest thermal window for biomass productivity and development. 5. The present results showed that the performance (ϕ3t) of the tested food webs is influenced in a top-down fashion, where the intra-specific variation of the food web, namely the host plant, played a major role in the productivity of each of the subsequent trophic levels. 6. The ϕ3t suggested that exposure to high and low temperatures might severely affect the effectiveness of A. ervi as a biocontrol agent of the aphid M. euphorbiae in bell pepper and potato crops. [ABSTRACT FROM AUTHOR]

Access to a rich diversity of flowering plants is very important for the development of honey bee colonies introduced in crops for pollination. The aim of this observational study was to determine the impact of surrounding pollen diversity on the health of honey bee colonies introduced in lowbush blueberries ( Vaccinium angustifolium Ait.) in June and cranberries ( Vaccinium macrocarpon Ait.) in July. The results suggest that monocultures of lowbush blueberries are not suitable for optimal brood rearing. In the blueberry environments we studied, the dominant pollen collected by honey bees were Alnus Mill. spp. and Taraxacum officinale F.H. Wigg., which are deficient in some essential amino acids. Significant reduction of brood rearing during honey bees' stay in blueberry monocultures in June may, therefore, be explained by nutritional deficiencies. In July, the polliniferous flora in the vicinity of cranberry monocultures was poorer but of better nutritional quality. Pollen analysis allowed the identification of Brassicaceae, Trifolium L. spp., and V. macrocarpon as the three dominant taxa collected by honey bees during this period. The complete lists of plant taxa foraged by honey bees for pollen during the pollination of lowbush blueberries and cranberries are provided. [ABSTRACT FROM AUTHOR]

Drosophila suzukii is an invasive pest and economic threat to berry crops in Europe and the Americas. Current methods of control of this pest rely primarily on frequent applications of insecticides; therefore, there is a need for alternative control methods to reduce insecticide reliance. In this study, we evaluated the biological control potential of three parasitoid wasps: Diglyphus isaea, Muscidifurax raptorellus and Pachycrepoideus vindemmiae, and four predators: Chrysoperla carnea, Dicyphus hesperus, Orius insidiosus and Podisus maculiventris. Experiments were conducted for 15 days under controlled conditions in experimental arenas with D. suzukii females and raspberries, allowing for all life stages of D. suzukii to be available to natural enemies. Results showed the first evidence of M. raptorellus's ability to parasitize D. suzukii, resulting in a 40% reduction. Orius insidiosus, P. vindemmiae and C. carnea were also efficient, reducing D. suzukii numbers by 49%, 43% and 32%, respectively. Predator preferences for each D. suzukii life stage were assessed. The clutch size, sex ratio and adult size variability of D. suzukii pupal parasitoids were also evaluated. This study expands the list of species that can effectively parasitize D. suzukii and provides new insights into the biological responses of M. raptorellus to D. suzukii pupae. [ABSTRACT FROM AUTHOR]

In recent years, populations of honey bees and other pollinators have been reported to be in decline worldwide. A number of stressors have been identified as potential contributing factors, including the extensive prophylactic use of neonicotinoid insecticides, which are highly toxic to bees, in agriculture. While multiple routes of exposure to these systemic insecticides have been documented for honey bees, contamination from puddle water has not been investigated. In this study, we used a multi-residue method based on LC-MS/MS to analyze samples of puddle water taken in the field during the planting of treated corn and one month later. If honey bees were to collect and drink water from these puddles, our results showed that they would be exposed to various agricultural pesticides. All water samples collected from corn fields were contaminated with at least one neonicotinoid compound, although most contained more than one systemic insecticide. Concentrations of neonicotinoids were higher in early spring, indicating that emission and drifting of contaminated dust during sowing raises contamination levels of puddles. Although the overall average acute risk of drinking water from puddles was relatively low, concentrations of neonicotinoids ranged from 0.01 to 63 µg/L and were sufficient to potentially elicit a wide array of sublethal effects in individuals and colony alike. Our results also suggest that risk assessment of honey bee water resources underestimates the foragers' exposure and consequently miscalculates the risk. In fact, our data shows that honey bees and native pollinators are facing unprecedented cumulative exposure to these insecticides from combined residues in pollen, nectar and water. These findings not only document the impact of this route of exposure for honey bees, they also have implications for the cultivation of a wide variety of crops for which the extensive use of neonicotinoids is currently promoted. [ABSTRACT FROM AUTHOR]

Simple Summary: Pollinators are essential to produce fruits in apple production. Bumble bees are among the most effective pollinators in orchards during the blooming season, yet they are often threatened by the high levels of pesticide use in apple production. Hedgerows and flower strips are infrequently sprayed by pesticides and are thus potentially good shelter for bumble bees. This study evaluated the influence of landscaping in the form of hedgerows and flower strips on the abundance and number of bumble bee species found in apple orchards. The number of bumble bee species found in orchards with hedgerows or flower strips was higher than in orchards without such landscape enhancements. Similarly, three species were more abundant in orchards with landscaping than orchards without those enhancements. Our work provides additional evidence that landscaping in the form of hedgerows and/or flower strips improves bumble bee presence in apple orchards and should therefore be considered as a means to enhance and ensure pollination within farms. Bumble bees are among the most effective pollinators in orchards during the blooming period, yet they are often threatened by the high levels of pesticide use in apple production. This study aimed to evaluate the influence of landscape enhancements (e.g., hedgerows, flower strips) on bumble bee queens in apple orchards. Bumble bee queens from 12 orchards in southern Québec (Canada) were marked, released, and recaptured in the springs and falls of 2017 to 2019. Half of the 12 orchards had landscape enhancements. Apples were harvested in 2018 and 2019 to compare their quality (weight, diameter, sugar level, and seed number) in sites with and without landscape enhancements. Species richness, as well as the occurrence of three species out of eight, was higher in orchards with landscape enhancements than in orchards without such structures. The occurrence of Bombus ternarius was lower in orchards with high levels of pesticide use. Apples had fewer seeds when collected in orchards with landscape enhancements and were heavier in orchards that used more pesticides. Our work provides additional evidence that landscape enhancements improve bumble bee presence in apple orchards and should therefore be considered as a means to enhance pollination within farms. [ABSTRACT FROM AUTHOR]

While honey bee exposure to systemic insecticides has received much attention, impacts on wild pollinators have not been as widely studied. Neonicotinoids have been shown to increase acetylcholinesterase (AChE) activity in honey bees at sublethal doses. High AChE levels may therefore act as a biomarker of exposure to neonicotinoids. This two-year study focused on establishing whether bumble bees living and foraging in agricultural areas using neonicotinoid crop protection show early biochemical signs of intoxication. Bumble bee colonies (Bombus impatiens) were placed in two different agricultural cropping areas: 1) control (≥3 km from fields planted with neonicotinoid-treated seeds) or 2) exposed (within 500 m of fields planted with neonicotinoid-treated seeds), and maintained for the duration of corn sowing. As determined by Real Time qPCR, AChE mRNA expression was initially significantly higher in bumble bees from exposed sites, then decreased throughout the planting season to reach a similar endpoint to that of bumble bees from control sites. These findings suggest that exposure to neonicotinoid seed coating particles during the planting season can alter bumble bee neuronal activity. To our knowledge, this is the first study to report in situ that bumble bees living in agricultural areas exhibit signs of neonicotinoid intoxication. [ABSTRACT FROM AUTHOR]