Introducing the INSIGNIA project: Environmental monitoring of pesticides use through honey bees

INSIGNIA aims to design and test an innovative, non-invasive, scientifically proven citizen science environmental monitoring protocol for the detection of pesticides via honey bees. It is a pilot project initiated and financed by the European Commission (PP-1-1-2018; EC SANTE). The study is being carried out by a consortium of specialists in honey bees, apiculture, chemistry, molecular biology, statistics, analytics, modelling, extension, social science and citizen science from twelve countries. Honey bee colonies are excellent bio-samplers of biological material such as nectar, pollen and plant pathogens, as well as non-biological material such as pesticides or airborne contamination. Honey bee colonies forage over a circle of about 1 km radius, increasing to several km if required depending on the availability and attractiveness of food. All material collected is concentrated in the hive, and the honey bee colony can provide four main matrices for environmental monitoring: bees, honey, pollen and wax. For pesticides, pollen and wax are the focal matrices. Pollen collected in pollen traps will be sampled every two weeks to record foraging conditions. During the season, most of pollen is consumed within days, so beebread can provide recent, random sampling results. On the other hand wax acts as a passive sampler, building up an archive of pesticides that have entered the hive. Alternative in-hive passive samplers will be tested to replicate wax as a “pesticide-sponge”. Samples will be analysed for the presence of pesticides and the botanical origin of the pollen using an ITS2 DNA metabarcoding approach. Data on pollen and pesticides will be then be combined to obtain information on foraging conditions and pesticide use, together with evaluation of the CORINE database for land use and pesticide legislation to model the exposure risks to honey bees and wild bees. All monitoring steps from sampling through to analysis will be studied and tested in four countries in year 1, and the best practices will then be ring-tested in nine countries in year 2. Information about the course of the project and its results and publications will be available in the INSIGNIA website www.insignia-bee.eu.info:eu-repo/semantics/publishedVersio

Genetic variability and expression of phenological and morphological differences in populations of Delia radicum (Diptera: Anthomyiidae)

International audienc

Larval respiratory systems of two anthomyiid files, Delia radicum and Delia antiqua (Diptera : Anthomyiidae)

International audienceThe first-instar larvae of Delia radicum (L.) and Delia antiqua (Meigen) enter host plants to feed in galleries. These galleries can be filled by a liquid resulting from the putrefaction of the host. In this study, we show that D. radicum and D. antiqua larvae have a metapneustic respiratory system in the first instar and an amphipneustic respiratory system in the second instar, as observed in the majority of cyclorrhaphous Diptera. In addition, we observed four spatulate, ramified structures on the postabdominal spiracles in all three larval instars. We propose that these structures facilitate gas exchange (CO2 and O-2), especially in the first-instar larvae when they feed in liquid-filled gallerie

Proteome of Aedes aegypti larvae in response to infection by the intracellular parasite Vavraia culicis

International audienc

Geographical origin of an introduced pest species, Delia radicum (Diptera : Anthomyiidae), determined by RAPD analysis and egg micromorphology

International audienc

Etude préliminaire du déterminisme génétique controlant l'expression de l'émergence bimodale de Delia radicum (Diptera : anthomyiidae)

SupplémentNational audienc

Facultative virulence: a strategy to manipulate hosts ?

International audienc

Behavioural manipulation in a grasshopper harbouring hairworm: a proteomics approach

The parasitic Nematomorph hairworm, Spinochordodes tellinii (Camerano) develops inside the terrestrial grasshopper, Meconema thalassinum (De Geer) (Orthoptera: Tettigoniidae), changing the insect's responses to water. The resulting aberrant behaviour makes infected insects more likely to jump into an aquatic environment where the adult parasite reproduces. We used proteomics tools (i.e. two-dimensional gel electrophoresis (2-DE), computer assisted comparative analysis of host and parasite protein spots and MALDI-TOF mass spectrometry) to identify these proteins and to explore the mechanisms underlying this subtle behavioural modification. We characterized simultaneously the host (brain) and the parasite proteomes at three stages of the manipulative process, i.e. before, during and after manipulation. For the host, there was a differential proteomic expression in relation to different effects such as the circadian cycle, the parasitic status, the manipulative period itself, and worm emergence. For the parasite, a differential proteomics expression allowed characterization of the parasitic and the free-living stages, the manipulative period and the emergence of the worm from the host. The findings suggest that the adult worm alters the normal functions of the grasshopper's central nervous system (CNS) by producing certain ‘effective’ molecules. In addition, in the brain of manipulated insects, there was found to be a differential expression of proteins specifically linked to neurotransmitter activities. The evidence obtained also suggested that the parasite produces molecules from the family Wnt acting directly on the development of the CNS. These proteins show important similarities with those known in other insects, suggesting a case of molecular mimicry. Finally, we found many proteins in the host's CNS as well as in the parasite for which the function(s) are still unknown in the published literature (www) protein databases. These results support the hypothesis that host behavioural changes are mediated by a mix of direct and indirect chemical manipulation

Natural history of host-parasite interactions

Parasite-induced alteration of host behaviour is a widespread transmission strategy among pathogens. Understanding how it works is an exciting challenge from both a mechanistic and an evolutionary perspective. In this review, we use key examples to examine the proximate mechanisms by which parasites are known to control the behaviour of their hosts. Special attention is given to the recent developments of post-genomic tools, such as proteomics, for determining the genetic basis of parasitic manipulation. We then discuss two novel perspectives on host manipulation (mafia-like strategy and exploitation of host compensatory responses), arguing that parasite-manipulated behaviours could be the result of compromises between host and parasite strategies. Such compromises may occur when collaborating with the parasite is less costly for the host in terms of fitness than is resisting parasite-induced changes. Therefore, even when changes in host behaviour benefit the parasite, the host may still play some role in the switch in host behaviour. in other words, the host does not always become part of the parasite's extended phenotype. For example, parasites that alter host behaviour appear to induce widely disseminated changes in the hosts' central nervous system, as opposed to targeted attacks on specific neural circuits. In some host-parasite systems, the change in host behaviour appears to require the active participation of the host (e.g., via host immune-neural connections). Even when the change in host behaviour results in clear fitness benefits for the parasite, these behavioural changes may sometimes be produced by the host. Changes in host behaviour that decrease the fitness costs of infection could be selected for, even if these changes also benefit the parasite

Biochemical and histological changes in the brain of the cricket Nemobius sylvestris infected by the manipulative parasite Paragordius tricuspidatus (Nematomorpha)

Hairworms (nematomorpha) alter the behaviour of their insect hosts, making them commit ‘suicide’ by jumping into an aquatic environment required by the adult parasite for the continuation of its life cycle. To explore the physiological and neuronal basis of this behavioural manipulation, we first performed a biochemical study to quantify different neurotransmitters or neuromodulators (monoamines and amino acids) in the brain of crickets (Nemobius sylvestris) uninfected and infected by the hairworm Paragordius tricuspidatus. We also analysed several polyamines and amino-acids having no known neuromodulatory function. The presence/absence of the parasite explained the largest part of the variation in compound concentrations, with infected individuals displaying on average lower concentrations than uninfected individuals. However, for three amino acids (taurine, valine and tyrosine), a significant part of the variation was also correlated with the manipulative process. In order to compare neurogenesis between infected and uninfected crickets, we also performed a histological study on mushroom bodies in the cricket's brain. The mitotic index exhibited a two-fold increase in infected crickets as compared with uninfected crickets. This is the first study to document changes in the brain of insects infected by nematomorphs