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Combined stress from parasites, pesticides and lack of flowers drives bee declines
Bees are subject to numerous pressures in the modern world. The abundance and diversity of flowers has declined, bees are chronically exposed to cocktails of agrochemicals, and they are simultaneously exposed to novel parasites accidentally spread by humans. Climate change is likely to exacerbate these problems in the future. Stressors do not act in isolation; for example pesticide exposure can impair both detoxification mechanisms and immune responses, rendering bees more susceptible to parasites. It seems certain that chronic exposure to multiple, interacting stressors is driving honey bee colony losses and declines of wild pollinators, but such interactions are not addressed by current regulatory procedures and studying these interactions experimentally poses a major challenge. In the meantime, taking steps to reduce stress on bees would seem prudent; incorporating flower-rich habitat into farmland, reducing pesticide use through adopting more sustainable farming methods, and enforcing effective quarantine measures on bee movements are all practical measures that should be adopted. Effective monitoring of wild pollinator populations is urgently needed to inform management strategies into the future
A mechanistic framework to explain the immunosuppressive effects of neurotoxic pesticides on bees
1. There is growing concern that declines in some managed and wild bee pollinator populations threaten biodiversity, the functioning of vital ecological processes and sustainable food production on a global scale.
2. In recent years, there has been increasing evidence that sub-lethal exposure to the neurotoxic class of insecticides (neonicotinoids) can undermine pollinator immunocompetence and amplify the effects of diseases, which have been suspected to be one of the drivers of pollinator declines. However, exactly how neonicotinoids might inhibit pollinator immunity remains elusive.
3. Here we put forward a mechanistic framework to explain the effects of neurotoxic pesticides on insect immunocompetence. We propose that there is a close ontogenetic connection between the cellular arm (haemocytes) of the insect immune and nervous systems, and that this connection makes the immune system of pollinators and other insects inherently susceptible to interference by neurotoxins such as neonicotinoids at sublethal doses.
4. Investigation of this connection is urgently needed to confirm the validity of this framework, and develop a clear, mechanistically-informed understanding of the interplay between neonicotinoids and disease ecology in pollinators. This in turn may enable us to develop strategies to mitigate impacts of neurotoxins on pollinators and/or enhance their impacts on pests
Architectures of Emergency. Sentinel operations for a rapidly changing environment
[EN] The declaration of an emergency is given by various protocols that respond to a series of interventions driven by an environmental urgency (Anderson 2017), designed by global networks of experts that mobilize advertising modes of economic development in the face of environmental collapse (Goh 2021). This research proposes a different imaginary of the Emergency. This reflection aims to resignify the Emergency from the embodied experiences of the disruptive events we live, opening the discussion on the frictions between a normative world based on human security and the modalities of militant movements dedicated to redressing social, environmental, and economic inequalities (Whyte 2018). In this sense, we develop the idea of sentinel modes of care that reflect the affective scaffolding of life-related to the environment and potential catastrophe (Wright, Plahe, and Jack 2022). A state of constant alertness characterizes sentinel care within a more-than-human register of the relationship and potentialities of the territory. This text aims to position itself on emergency protocols while exploring other imaginaries and their impact on spatial practices.Mompean Botias, E. (2023). Architectures of Emergency. Sentinel operations for a rapidly changing environment. Editorial Universitat Politècnica de València. 598-611. https://doi.org/10.4995/VIBRArch2022.2022.1527459861
Genomic and functional analyses unveil the response to hyphal wall stress in Candida albicans cells lacking β(1,3)-glucan remodeling
Class 2: Transcripts that are less abundant in the phr1Î mutant than in the wild type. (XLSX 39 kb
Monitoring neonicotinoid exposure for bees in rural and peri-urban areas of the UK during the transition from pre- to post-moratorium
Concerns regarding the impact of neonicotinoid exposure on bee populations recently led to an EU-wide moratorium on the use of certain neonicotinoids on flowering crops. Currently evidence regarding the impact, if any, the moratorium has had on bees’ exposure is limited. We sampled pollen and nectar from bumblebee colonies in rural and peri-urban habitats in three UK regions; Stirlingshire, Hertfordshire and Sussex. Colonies were sampled over three years; prior to the ban (2013), during the initial implementation when some seed-treated winter-sown oilseed rape was still grown (2014), and following the ban (2015). To compare species-level differences, in 2014 only, honeybee colonies in rural habitats were also sampled. Over half of all samples were found to be contaminated (n=408), with thiamethoxam being the compound detected at the highest concentrations in honeybee- (up to 2.29 ng/g in nectar in 2014, median≤0.1 ng/g, n=79) and bumblebee-collected pollen and nectar (up to 38.77 ng/g in pollen in 2013, median ≤0.12 ng/g, n=76). Honeybees were exposed to higher concentrations of neonicotinoids than bumblebees in 2014. While neonicotinoid exposure for rural bumblebees declined post-ban (2015), suggesting a positive impact of the moratorium, the risk of neonicotinoid exposure for bumblebees in peri-urban habitats remained largely the same between 2013 and 2015
A Bacterial Shortcut to Amyloidosis
21 p.-10 fig.The synthetic bacterial prionoid RepA-WH1 causes a vertically transmissible amyloid proteinopathy in Escherichia coli that inhibits growth and eventually kills the cells. Recent in vitro studies show that RepA-WH1 builds pores through model lipid membranes, suggesting a possible mechanism for bacterial cell death. By comparing acutely (A31V) and mildly (ΔN37) cytotoxic mutant variants of the protein, we report here that RepA-WH1(A31V) expression decreases the intracellular osmotic pressure and compromise bacterial viability under either aerobic or anaerobic conditions. Both are effects expected from threatening membrane integrity and are in agreement with findings on the impairment by RepA-WH1(A31V) of the proton motive force (PMF)-dependent transport of ions (Fe3+) and ATP1 synthesis. Systems approaches reveal that, in aerobiosis, the PMF-independent respiratory dehydrogenase NdhII is induced in response to the reduction in intracellular levels of iron. While NdhII is known to generate H2O2 as a by-product of the autoxidation of its FAD cofactor, key proteins in the defense against oxidative stress (OxyR, KatE), together with other stress-resistance factors, are sequestered by co-aggregation with the RepA-WH1(A31V) amyloid. Our findings suggest a route for RepA-WH1 toxicity in bacteria: a primary hit of damage to the membrane, compromising bionergetics, triggers a stroke of oxidative stress, which is exacerbated due to the aggregation-dependent inactivation of enzymes and transcription factors that enable the cellular response to such injury. The proteinopathy caused by the prion-like protein RepA-WH1 in bacteria recapitulates some of the core hallmarks of human amyloid diseases.This work has been supported by grants from Spanish AEI / EU-FEDER (BIO2012-30852, BIO2015- 68730-R and CSD2009-00088) and CSIC (i-LINK0889) to R.G. We acknowledge support of the publication fee by the CSIC Open Access Support Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe
Ornamental plants on sale to the public are a significant source of pesticide residues with implications for the health of pollinating insects
Garden centres frequently market nectar- and pollen-rich ornamental plants as “pollinator-friendly”, however these plants are often treated with pesticides during their production. There is little information on the nature of pesticide residues present at the point of purchase and whether these plants may actually pose a threat to, rather than benefit, the health of pollinating insects. Using mass spectrometry analyses, this study screened leaves from 29 different ‘bee-friendly’ plants for 8 insecticides and 16 fungicides commonly used in ornamental production. Only two plants (a Narcissus and a Salvia variety) did not contain any pesticide and 23 plants contained more than one pesticide, with some species containing mixtures of 7 (Ageratum houstonianum) and 10 (Erica carnea) different agrochemicals. Neonicotinoid insecticides were detected in more than 70% of the analysed plants, and chlorpyrifos and pyrethroid insecticides were found in 10% and 7% of plants respectively. Boscalid, spiroxamine and DMI-fungicides were detected in 40% of plants. Pollen samples collected from 18 different plants contained a total of 13 different pesticides. Systemic compounds were detected in pollen samples at similar concentrations to those in leaves. However, some contact (chlorpyrifos) and localised penetrant pesticides (iprodione, pyroclastrobin and prochloraz) were also detected in pollen, likely arising from direct contamination during spraying. The neonicotinoids thiamethoxam, clothianidin and imidacloprid and the organophosphate chlorpyrifos were present in pollen at concentrations between 6.9 and 81 ng/g and at levels that overlap with those known to cause harm to bees. The net effect on pollinators of buying plants that are a rich source of forage for them but simultaneously risk exposing them to a cocktail of pesticides is not clear. Gardeners who wish to gain the benefits without the risks should seek uncontaminated plants by growing their own from seed, plant-swapping or by buying plants from an organic nursery
MAPEAR LA EMERGENCIA EN UCRANIA
During the months following Russia's invasion attempt of Ukraine, our endeavor was to document the rising practices resulting from the state of emergency induced by the war. Particularly in Ukraine, the ongoing experience of invasion, coupled with the looming threat of nuclear disasters, has given rise to practices that recognize fragility as a mode of existence. In times of emergency, everyday routines are regulated and identified through established protocols. Tracing and repairing damage; creating shelters, marking them, and even mapping all of these practices became routine acts of collective care.ALIC
De la concertation territoriale à l'expérimentation en plein champs, différents leviers pour accompagner les acteurs d'un territoire agricole à façonner des paysages durablement favorables à des productions oléagineuses et des productions de miel
Les interactions entre les abeilles et leur milieu sont multiples, complexes, incomprises pour certaines et parfois même controversées. Cette complexité se répercute parfois dans les échanges entre les acteurs liés de près ou de loin à ces insectes pollinisateurs qui évoluent sur un même territoire. Dans ce contexte, l'institut technique et scientifique de l'apiculture et de la pollinisation (ITSAP–Institut de l'abeille), après avoir fait le constat qu'apiculteurs et agriculteurs ne partagent pas toujours la même perception de leur territoire, travaille depuis quelques années à accompagner ces acteurs dans la construction de leviers favorables au maintien durable de ces différentes activités agricoles sur leur territoire. Nous illustrerons cette dynamique à travers différents formats d'actions : l'échange de connaissances dans des ateliers de concertation sous forme de jeu de rôles et l'acquisition et le partage de références dans une expérimentation en plein champs
Flower sharing and pollinator health: a behavioural perspective
This is the author accepted manuscript. The final version is available from the Royal Society via the DOI in this recordDisease is an integral part of any organisms’ life, and bees have evolved immune responses and a suite of hygienic behaviours to keep them at bay in the nest. It is now evident that flowers are another transmission hub for pathogens and parasites, raising questions about adaptations that help pollinating insects stay healthy while visiting hundreds of plants over their lifetime. Drawing on recent advances in our understanding of how bees of varying size, dietary specialisation and sociality differ in their foraging ranges, navigational strategies and floral resource preferences, we explore the behavioural mechanisms and strategies that may enable foraging bees to reduce disease exposure and transmission risks at flowers by partitioning overlapping resources in space and in time. By taking a novel behavioural perspective, we highlight the missing links between disease biology and the ecology of plant-pollinator relationships, critical for improving the understanding of disease transmission risks and the better design and management of habitat for pollinator conservation.Biotechnology & Biological Sciences Research Council (BBSRC)UKRIEuropean Regional Development Fund (ERDF
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