New insights into honey bee (Apis mellifera) pheromone communication. Is the queen mandibular pheromone alone in colony regulation?

<p>Abstract</p> <p>Background</p> <p>In social insects, the queen is essential to the functioning and homeostasis of the colony. This influence has been demonstrated to be mediated through pheromone communication. However, the only social insect for which any queen pheromone has been identified is the honey bee (<it>Apis mellifera</it>) with its well-known queen mandibular pheromone (QMP). Although pleiotropic effects on colony regulation are accredited to the QMP, this pheromone does not trigger the full behavioral and physiological response observed in the presence of the queen, suggesting the presence of additional compounds. We tested the hypothesis of a pheromone redundancy in honey bee queens by comparing the influence of queens with and without mandibular glands on worker behavior and physiology.</p> <p>Results</p> <p>Demandibulated queens had no detectable (E)-9-oxodec-2-enoic acid (9-ODA), the major compound in QMP, yet they controlled worker behavior (cell construction and queen retinue) and physiology (ovary inhibition) as efficiently as intact queens.</p> <p>Conclusions</p> <p>We demonstrated that the queen uses other pheromones as powerful as QMP to control the colony. It follows that queens appear to have multiple active compounds with similar functions in the colony (pheromone redundancy). Our findings support two hypotheses in the biology of social insects: (1) that multiple semiochemicals with synonymous meaning exist in the honey bee, (2) that this extensive semiochemical vocabulary exists because it confers an evolutionary advantage to the colony.</p

E-β-Ocimene, a Volatile Brood Pheromone Involved in Social Regulation in the Honey Bee Colony (Apis mellifera)

Background: In honey bee colony, the brood is able to manipulate and chemically control the workers in order to sustain their own development. A brood ester pheromone produced primarily by old larvae (4 and 5 days old larvae) was first identified as acting as a contact pheromone with specific effects on nurses in the colony. More recently a new volatile brood pheromone has been identified: E-β-ocimene, which partially inhibits ovary development in workers. [br/] Methodology and Principal Finding: Our analysis of E-β-ocimene production revealed that young brood (newly hatched to 3 days old) produce the highest quantity of E-b-ocimene relative to their body weight. By testing the potential action of this molecule as a non-specific larval signal, due to its high volatility in the colony, we demonstrated that in the presence of E-β-ocimene nest workers start to forage earlier in life, as seen in the presence of real brood. [br/] Conclusions/Significance: In this way, young larvae are able to assign precedence to the task of foraging by workers in order to increase food stores for their own development. Thus, in the complexity of honey bee chemical communication, E-β- ocimene, a pheromone of young larvae, provides the brood with the means to express their nutritional needs to the workers

A composição química da feromona de alarme produzida pela abelha ibéria (Apis mellifera Iberiensis)

As abelhas, como a maioria dos insectos sociais, produzem feromonas que controlam parcialmente muitos aspectos comportamentais e fisiológicos individuais e da colónia, como a resposta de alarme, orientação e o controlo da rainha sobre as obreiras [1]. A feromona de alarme é um dos elementos-chave no comportamento defensivo das abelhas. O “aroma a banana” destes voláteis, presentes na colmeia quando esta é perturbada, é facilmente reconhecido pelos apicultores. Esta feromona é constituída por uma mistura complexa de compostos produzidos maioritariamente nas glândulas de Koschevnikov e nas bainhas do ferrão, sendo acumulada na membrana setosa, o que permite uma rápida dispersão sempre que o ferrão é libertado. Mais de quarenta compostos foram já identificados, entre os quais compostos oxigenados, bastante voláteis, envolvidos na sinalização do alarme. Esta complexidade química cria uma assinatura única para esta feromona, sendo específica para cada tipo de abelha [2]. Neste trabalho pretendeu-se analisar a feromona de alarme emitida pelas obreiras da abelha ibérica (Apis mellifera iberiensis) procedendo-se à otimização do processo de extração e análise da feromona. Para isso, foram removidos e extraídos os aparelhos do ferrão de abelhas recolectoras capturadas à entrada de colónias de abelhas ibéricas provenientes de um apiário experimental situado em Nogueira (Bragança). Após a extração, efetuou-se a análise por cromatografia gasosa acoplada a espectrometria de massa (GC-MS) onde foram identificados cerca de 20 compostos, entre os quais o, álcool benzílico, o octanol, o 2-nonanol, acetato de isopentilo, o eicosenol, o 2-decenol e o ácido 9- octadecenóico, sendo estes últimos descritos pela primeira vez em feromonas de Apis mellifera. O acetato de isopentilo e o eicosenol são os principais responsáveis pelo desencadear da resposta ao comportamento de alarme.Soraia I. Falcão agradece à FCT pela bolsa Post-Doc SFRH/BPD/118987/2016. Os autores agradecem à Fundação para a Ciência e Tecnologia (FCT, Portugal) e ao FEDER sob o programa PT2020 pelo financiamento ao CIMO (UID/AGR/00690/2013).info:eu-repo/semantics/publishedVersio

Constraints on adaptive mutations in the codling moth <em>Cydia pomonella</em> (L.): measuring fitness trade-offs and natural selection

International audienceAdaptive changes in populations encountering a new environment are often constrained by deleterious pleiotropic interactions with ancestral physiological functions. Evolutionary responses of populations can thus be limited by natural selection under fluctuating environmental conditions, if the adaptive mutations are associated with pleiotropic fitness costs. In this context, we have followed the evolution of the frequencies of insecticide-resistant mutants of Cydia pomonella when reintroduced into an untreated environment. The novel set of selective forces after removal of insecticide pressure led to the decline of the frequencies of resistant phenotypes over time, suggesting that the insecticideadapted genetic variants were selected against the absence of insecticide (with a selective coefficient estimated at 0.11). The selective coefficients were also estimated for both the major cytochrome P450-dependent monooxygenase (MFO) and the minor glutathione S-transferase (GST) systems (0.17 and negligible, respectively), which have been previously shown to be involved in resistance. The involvement of metabolic systems acting both through xenobiotic detoxification and biosynthetic pathways of endogenous compounds may be central to explaining the deleterious physiological consequences resulting from pleiotropy of adaptive changes. The estimation of the magnitude of the fitness cost associated with insecticide resistance in C. pomonella suggests that resistance management strategies exclusively based on insecticide alternations would be unlikely to delay such a selection proces

Raisonner la lutte chimique. Analyse d'une récente perte d'efficacité du piège sexuel carpocapse : quelle relation avec la résistance aux insecticides ?

National audienc

Résistance aux insecticides et phéromones sexuelles chez le carpocapse des pommes Cydia pomonella L.

National audienc

Identification d’une nouvelle phéromone larvaire : l’E-β-ocimene permettant la régulation du développement ovarien des ouvrières chez l’abeille domestique

National audienceDans une colonie d’abeilles sans reine ni couvain, les ouvrières tendent à devenir fertiles et investir leur énergie dans la ponte d’oeuf non-fécondés. Afin de maintenir une certaine stabilité dans l’organisation de la colonie et prévenir ce détournement de l’investissement énergétique des ouvrières, la reine garantie son statut de seule reproductrice et le couvain accapare le soin des ouvrières. Pour cela, ils émettent des phéromones peu volatiles. La phéromone mandibulaire (principalement le 9-ODA) émis par la reine ainsi qu’un mélange de 10 esters émis par le couvain. Ces composés permettent une castration chimique partielle des ouvrières. Cependant, parmi les deux facteurs de régulation de la maturation ovarienne des ouvrières, il semble que la présence de couvain soit le plus actif. Nous nous sommes donc demandé si les larves ne pourraient pas émettre des molécules très volatiles ayant un rôle sur le développement ovarien des ouvrières. Les composés volatiles larvaires ont donc été prélevés par Microextraction sur phase solide (SPME), puis analysés et identifiés par GC-MS. Le pic majeur retrouvé dans tous les échantillons est une molécule hautement volatile, l’E-β- ocimene. Nous avons testé l’effet de cette molécule sur la croissance des ovaires d’ouvrières élevées en cagette. Les résultats indiquent un effet inhibiteur significatif de l’E-β-ocimene sur le développement ovarien des ouvrières. Cette nouvelle phéromone, dont les effets sont identiques à ceux produits par la phéromone mandibulaire de la reine, montre que différents acteurs, utilisant différentes phéromones, peuvent induire un même effet sur le même organisme cible. De nouveaux tests sont nécessaires pour comprendre si les trois phéromones décris ici, régulant la fertilité de la colonie d’abeilles, peuvent agir ensemble pour une castration chimique totale des ouvrière

Effet d'une exposition larvaire à un analogue de l'hormone juvénile sur l'acceptation et le comportement social des adultes au sein d'une colonie

Effet d'une exposition larvaire à un analogue de l'hormone juvénile sur l'acceptation et le comportement social des adultes au sein d'une colonie. 3. Journées de la Recherche Apicol