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In the parasitoid genus Sclerodermus, multiple foundresses produce and care for communal broods on large hosts, which can lead to greater reproductive success for group members than attempting to reproduce alone. We explore the consequences of foundress group size on the benefits of cooperative brooding and on brood sex ratios by providing groups of 10-55 foundresses with a single host and no alternative reproductive options. Within this range, increasing foundress group size leads to increasingly common failure in brood production and diminished per capita success. Group production of adult offspring declines once foundress number reaches around 25. Brood failure is usually at the early developmental stages, and current evidence suggests that there may be competition among foundresses for oviposition sites, possibly involving reproductive dominance and ovicide, which also delays initial brood production. Once broods become established, their rate of development is enhanced by large foundress numbers. The sex ratios of broods are very strongly female biased, irrespective of the foundress number. As this bias is not easily explained by standard models of local mate competition or by a recent model of local resource enhancement, we suggest an explanation based on control of sex allocation by a minority of dominant foundresses, which monopolise the production of adult males.

Understanding the responses of insect herbivores to plant chemical defences is pivotal for the management of crops and pests. However, the mechanisms of interaction are not entirely understood. In this study, we compared the whole transcriptome gene expression of the aphid Macrosiphum euphorbiae grown on two different varieties of tomato that differ in their inducible chemical defences. We used two isogenic lines of tomato with a shared genetic background that only differ in the presence of type IV glandular trichomes and their associated acylsucrose excretions. This works also reports a de novo transcriptome of the aphid M. euphorbiae. Subsequently, we identified a unique and distinct gene expression profile for the first time corresponding to aphid´s exposure to type IV glandular trichomes and acylsugars. The analysis of the aphid transcriptome shows that tomato glandular trichomes and their associated secretions are highly efficient in triggering stress-related responses in the aphid, and demonstrating that their role in plant defence goes beyond the physical impediment of herbivore activity. Some of the differentially expressed genes were associated with carbohydrate, lipid and xenobiotic metabolisms, immune system, oxidative stress response and hormone biosynthesis pathways. Also, the observed responses are compatible with a starvation syndrome. The transcriptome analysis puts forward a wide range of genes involved in the synthesis and regulation of detoxification enzymes that reveal important underlying mechanisms in the interaction of the aphid with its host plant and provides a valuable genomic resource for future study of biological processes at the molecular level using this aphid.

Butterflies of the genus Zerynthia often have different host plants in the genus Aristolochia in the different parts of their distribution range. In Mediterranean France the Southern Festoon reaches its North Western distribution limit, where it generally lays eggs on A. rotunda in either coastal wet meadows or riparian and garrigue habitats in the backcountry. In the study area (Hérault and Gard departments), its distribution range overlaps with that of the Spanish Festoon Zerynthia rumina at its north-eastern limits. The Spanish Festoon lays its eggs on A. pistolochia plants growing in dry garrigues in the backcountry. Three types of field observations were conducted to determine : (1) whether habitat variation influences the rates of egg deposition by the Southern Festoon, (2) the extent to which A. rotunda is the preferential host plant and (3) if both Southern and Spanish Festoons are specialised if they co-occur with both their host plants in proximity. We found that A. rotunda is the main host plant of the Southern Festoon in both habitats where it grows in Mediterranean France although egg laying was observed on A. clematitis and more rarely on A. paucinervis in coastal sites. Finally, in parapatry, Southern and Spanish Festoons exchange their host plants but remain both more specialised on a different host. Despite their protection status, destruction of their habitats by urbanisation and infrastructures are a major threat to these specialised butterflies., Dans leurs différentes aires de distribution, les papillons du genre Zerynthia présentent des plantes-hôtes diverses au sein du genre Aristolochia. En France méditerranéenne, où Z. polyxena, la Diane, est en limite nord-ouest de distribution, elle pond généralement sur A. rotunda qui pousse à la fois dans les prairies humides littorales et certaines garrigues d’arrière-pays. Dans la zone d’étude (départements de l’Hérault et du Gard), son aire de distribution chevauche celle de Z. rumina, la Proserpine, dans sa limite orientale. Cette dernière pond sur A. pistolochia qui pousse dans les garrigues sèches d’arrière-pays. Trois axes d’observations de terrain ont été définis afin de voir (1) si la fréquence de ponte de Z. polyxena varie dans ses différents habitats, (2) dans quelle mesure A. rotunda est réellement la plantehôte préférentielle de Z. polyxena et (3) si Z. polyxena et Z. rumina demeurent spécialistes lorsqu’elles partagent le même habitat avec leurs deux plantes-hôtes en mélange ou en étroite proximité. L’ensemble de ces travaux a bien conforté qu’A. rotunda est l’hôte privilégié de Z. polyxena dans ses deux grands habitats de France méditerranéenne bien que des pontes puissent être observées sur A. clematitis et plus rarement sur A. paucinervis sur les sites littoraux. En parapatrie, Z. polyxena et Z. rumina peuvent ponctuellement changer de plante-hôte même si elles conservent une préférence pour la leur. Malgré leur statut de protection, ces papillons spécialistes sont principalement menacés par la destruction de leurs habitats par l’urbanisation et l’implantation d’infrastructures., Gauthier Perrine, Manincor Natasha de, Picquenot Manon, Pons Virginie, Schumpp Ugo, Thompson John D. Spécificité et flexibilité dans la ponte de Zerynthia polyxena sur différentes espèces du genre Aristolochia en région méditerranéenne française / Specificity and flexibility of egg laying by Zerynthia polyxena on different species of Aristolochia in Mediterranean France. In: Ecologia mediterranea, tome 46 n°2, 2020. pp. 47-63.

The relationship between plants and insects is one of the greatest evolutionary stories in the history of life on earth. Their importance in global terrestrial ecosystem functioning is self evident, as both represent the most abundant life on the planet. While plant-insect interactions have received much attention and are easily manipulated in experimental investigations, there have been few broad-scale phylogenetic studies for circumscribed herbivorous groups. As a result, the evolutionary role of interspecific interactions in promoting herbivorous insect diversification, at both the global and local scales, remains unclear. Remarkably, one of the largest gaps in our evolutionary and ecological understanding includes the sap-feeding insects in the Auchenorrhyncha suborder (Hemiptera), which contain some of the largest, terrestrially dominant host-plant restricted insect groups known (e.g., Cicadas, planthoppers, and leafhoppers). The evolutionary success of Auchenorrhyncha is due, at least in part, to ancient associations with a consortium obligate bacterial endosymbionts that have persisted for over 260 million years. However, like their insect hosts, the diversity and evolutionary relationships of endosymbiont associations remain relatively unknown for most aucchenorrhynchan groups.The leafhoppers (Cicadomorpha: Cicadellidae) remain one of the largest, yet poorly understood insect families. Of the 22,000 currently described species, thousands remain to be described with an overall unknown diversity (some estimates suggest as many as 90% of tropical Cicadomorpha remain to be described). This is surprising, since they offer excellent models to understand ecological and biogeographic mechanisms of species diversification due to their strict host-plant specificity, limited dispersal, and high rates of local endemism. The cicadellid subfamily, Deltocephalinae, represents the largest leafhopper groups, yet their patterns of species diversification, host-plant use, and endosymbiont associations remain almost entirely unknown. This study used the Hawaiian Archipelago as a model system to investigate the roles of ecology, biogeography, and endosymbiont interactions in the diversification of the native Hawaiian leafhopper genus, Nesophrosyne (Cicadellidae: Deltocephalinae). The Hawaiian Islands offer a tractable natural laboratory to circumscribe and study plant-insect evolution due to their isolated, discrete and replicated nature, and high levels of endemism. Nesophrosyne represents one of the most diverse and ecologically dominant herbivore radiations on Hawai`i, but has eluded scientific attention for over 60 years. Species are obligate phloem feeders and are highly host-plant specific. Moreover, Nesophrosyne exhibits the quintessential characteristics of an adaptive radiation, including dramatic morphological adaptations to the endemic Hawaiian flora and adaptive diversification across the archipelago to fill habitat types from coastal to sub-alpine regions. The specific goals of this study were to 1) update the current taxonomic status of Nesophrosyne, 2) determine the diversity and phylogenetic relationships of species in the genus, 3) infer the roles of ecology and geology in the adaptive radiation, historical biogeography, and species diversification dynamics of Nesophrosyne, and 4) to reconstruct the global relationships of the dual obligate bacterial endosymbionts of Nesophrosyne and their rates of evolution.In the first chapter, the taxonomic history and status of Nesophrosyne was reviewed. The genus was redescribed, and the subgenus Nesoreias was synonymized with Nesophrosyne. Eight new species associated with the widespread host-plant species, Broussaisia arguta (Hydrangeaceae), were described. Results reveal morphologically cryptic diversity according to individual Hawaiian Islands and volcanoes within this group. A model usage of morphological and molecular characters was developed for future delimitation of species in Nesophrosyne. The second chapter reconstructed a comprehensive phylogeny for Nesophrosyne in order to determine the origins, species diversity, and host-plant use of the native Hawaiian leafhoppers. Results support a monophyletic Nesophrosyne, originating from the Western Pacific basin, with a sister-group relationship to the genus Orosius. Nesophrosyne species are characterized by high levels of morphologically cryptic diversity and local endemicity, comprising > 200 species. Species demonstrate four dominant patterns of host-plant specialization that shape species diversity: 1) diversification through host switching; 2) specialization on widespread hosts with allopatric speciation; 3) repeated, independent shifts to the same hosts; and, 4) absence or low abundance on some hosts, suggesting herbivore interactions may limit ecological opportunity.The third chapter inferred the roles of ecology and geology in the adaptive radiation, historical biogeography, and species diversification dynamics of Nesophrosyne. The molecular age of Nesophrosyne indicates a split from Orosius 4.5 million years ago (Ma), with a basal divergence on Hawai`i 3.2 Ma. The genus originated on Kaua`i and subsequently colonized younger islands as they formed. Ancestral host-plant reconstructions reveal that the plant families, Urticaceae and Rubiaceae, played important roles in the early diversification of Nesophrosyne. Results indicate that island geography have imposed significant barriers to continued gene flow, leading to extensive allopatric speciation and intra-island diversification. Finally, Nesophrosyne diversification dynamics show an initial burst in speciation rates, with a subsequent diversity-dependent decline, corresponding to island formation. Finally, chapter four examined the global relationships of Nesophrosyne's dual obligate, bacteriome restricted bacterial endosymbionts, `Candidatus Sulcia muelleri' and a novel β-proteobacterium in the `Ca. Nasuia' genus. A global bacterial phylogeny was reconstructed, revealing a shared origin for the β-proteobacterial lineages throughout Deltocephalinae genera, and potentially throughout Auchenorrhyncha. The bacteriome association and transovarial transmission of Nesophrosyne's endosymbionts were confirmed using Fluorescent in situ Hybridization techniques. Finally, inference of absolute molecular rates demonstrates highly elevated rates of molecular evolution - the fastest so far recorded. We propose a second species in the genus Nasuia to describe the novel β-proteobacterium in Nesophrosyne.Hawai`i has long been held as a model system to understand adaptive radiation and evolutionary biology, however my study is one of the first to test these patterns directly for a hyper-diverse endemic insect radiation, and for the suborder Auchenorrhyncha. The presented results illustrate that, in diverse herbivorous groups, multiple evolutionary processes play fundamental roles in species diversification, including associations with bacterial endosymbionts, host-plant specialization, insect-insect interactions, and the geologic formation of islands. These results develop both an understanding of how ecological and geological controls shape adaptive diversification in insects, and a general model for contextualizing species diversification in herbivorous insects.

Gall-inducing insects cause the development of specialised plant tissues (galls) that provide them with nutrition and some measure of protection from physical and biotic stresses. Their interaction with the plant is the most intimate metabolically of any herbivore group and is often associated with high host specificity. We survey the gall inducers that have become invasive pests of forest trees, most of which belong to just four insect families in three orders: Hemiptera (Adelgidae), Diptera (Cecidomyiidae) and Hymenoptera (Cynipidae and Eulophidae). Most are associated with introduction of plants on which they are specialists, but some have also shifted from introduced to native plant hosts. No formal comparative analysis of traits associated with success of establishment and subsequent range expansion has yet been made, and it is often hard to identify why one species has become a major range-expanding pest, while closely related and biologically very similar species have not. We provide an overview of biological traits likely to facilitate gall inducer range expansion, and highlight the importance of natural enemies in community impacts and biological control. Increasing global trade is likely to result in further range expansions by economically damaging species. The effects of climate change on the direction, frequency, and impact of gall inducer range expansions are likely to be complex and probably species-specific.

The indirect defence compounds termed herbivore induced plant volatiles (HIPVs), which are used to attract beneficial fauna, are one of the most effective biological control tools for the aggregation of natural enemies of key pests. The aim of this study was to test the attraction of three aphid predators of the Chrysopidae, Coccinellidae and Syrphidae families using synthetic formulations of four main HIPVs [methyl salicylate (MeSa), benzaldehyde (B), linalool (L) and farnesene (F)] alone and in binary combinations (MeSa + B; MeSa + F; MeSa + L; F + B; B + L; F + L) in an apple orchard in the Bursa province of Turkey. This study was the first demonstration of the attraction of these aphid predators to single and binary combinations of synthetic HIPVs in an apple orchard. A larger number of coccinellids were captured using single treatments of both B and F than with other HIPV combinations. Furthermore, the chrysopid individuals studied were significantly attracted to traps baited with single HIPVs. In addition, the binary combination of MeSa + L significantly attracted more Syrphids than in both single treatments and control traps. Thus, some of the HIPV's tested were found to have potential value for the congregation of aphid predators in apple orchards. University of Bursa Uludag, Scientific Research Unit, Bursa, Turkey [UAP (Z) -2010/45] This study was supported by University of Bursa Uludag, Scientific Research Unit, Bursa, Turkey, Grant Project No: UAP (Z) -2010/45.

© 2019 Wong, Lutz, Natera, Wang, Ng, Grigoriev, Martin, Roessner, Anderson and Plett. Plant roots co-inhabit the soil with a diverse consortium of microbes of which a number attempt to enter symbiosis with the plant. These microbes may be pathogenic, mutualistic, or commensal. Hence, the health and survival of plants is heavily reliant on their ability to perceive different microbial lifestyles and respond appropriately. Emerging research suggests that there is a pivotal role for plant root secondary metabolites in responding to microbial colonization. However, it is largely unknown if plants are able to differentiate between microbes of different lifestyles and respond differently during the earliest stages of pre-symbiosis (i.e., prior to physical contact). In studying plant responses to a range of microbial isolates, we questioned: (1) if individual microbes of different lifestyles and species caused alterations to the plant root metabolome during pre-symbiosis, and (2) if these early metabolite responses correlate with the outcome of the symbiotic interaction in later phases of colonization. We compared the changes of the root tip metabolite profile of the model tree Eucalyptus grandis during pre-symbiosis with two isolates of a pathogenic fungus (Armillaria luteobubalina), one isolate of a pathogenic oomycete (Phytophthora cinnamomi), two isolates of an incompatible mutualistic fungus (Suillus granulatus), and six isolates of a compatible mutualistic fungus (Pisolithus microcarpus). Untargeted metabolite profiling revealed predominantly positive root metabolite responses at the pre-symbiosis stage, prior to any observable phenotypical changes of the root tips. Metabolite responses in the host tissue that were specific to each microbial species were identified. A deeper analysis of the root metabolomic profiles during pre-symbiotic contact with six strains of P. microcarpus showed a connection between these early metabolite responses in the root with later colonization success. Further investigation using isotopic tracing revealed a portion of metabolites found in root tips originated from the fungus. RNA-sequencing also showed that the plant roots undergo complementary transcriptomic reprogramming in response to the fungal stimuli. Taken together, our results demonstrate that the early metabolite responses of plant roots are partially selective toward the lifestyle of the interacting microbe, and that these responses can be crucial in determining the outcome of the interaction.

The predator-prey system Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) and Tetranychus urticae (Koch) (Acari: Tetranychidae) represents the most studied and the most known system among the Acari. Because of the agronomical importance of the two mite species, a wealth of modelling studies investigated the interactions of the two species at the individual level. However, regional or global level works on this system are lacking, which is impeding the investigation of climate change effects on biological control effectiveness. Here we compile and geo-locate worldwide occurrences for the two species considered, based on literature, collection and field survey data. The datasets presented in this document gather most of the literature records of both species for which locality data were available for geo-referencing (1,037 for T. urticae and 126 for P. persimilis). Geo-located data from collections and field surveys including host-plants are also presented for the first time (322 for T. urticae and 65 for P. persimilis). Phytoseiulus persimilis is also reported for the first time from Kenya and La Martinique., Acarologia, 59, 301-307

Hyalesthes obsoletus, vektor biljnog patogena 'Candidatus (Ca.) Phytoplasma solani', smatra se polifagnom štetočinom od ekonomskog značaja u centralnoj Evropi i Mediteranu. Istraživanjima sprovedenim u jugoistočnoj Evropi, koja gravitira centru arela vrste i gde je zabeležen značajan broj 'Ca. P. solani'- uslovljenih biljnih bolesti, utvrđeno je postojanje četiri asocijacije vektora sa biljkama dualnim domaćinima: Convolvulus arvensis (Ca), Urtica dioica (Ud), Vitex agnus-castus (Vac) i Crepis foetida (Cf). Populaciono-genetičkim analizama mitohondrijskih i nuklearnih markera (mikrosatelita) utvrđena je kriptična diferencijacija simpatričkih (uključujući sintopske) i geografski udaljenih H. obsoletus populacija na tri filogenetičke linije uslovljene biljkom domaćinom: (1) Ca-Ud, (2) Vac i (3) Cf. Pored jasne diferencijacije na mitohondrijskim genima (1.1% - 1.5%) i mikrosatelita koji potvrđuju izdvajanje populacija u jedan od tri klastera prema biljci domaćinu (pripadnost >90%), podršku za izdizanje genetičke divergencije H. obsoletus sensu lato na nivo kriptične specijacije daje registrovana distanca u odnosu na morfološki najsrodniju vrstu - Hyalesthes thracicus (2.1% - 3.3%). Posledice specijalizacije i diferencijacije H. obsoletus sensu lato prema biljkama domaćinima na epidemiologiju 'Ca. P. solani' procenjene su multigenskom karakterizacijom izolata fitoplazme detektovanih (1) in situ u prirodnim epidemiološkim sistemima mediteranskih vinograda i (2) eksperimentima unakrsne inokulacije biljaka putem prirodno inficiranih populacija vektora. Potvrđena je osnovna epidemiološka divergencija 'Ca. P. solani' na tuf-a/-ab i tuf-b cikluse vezane za Ud i Ca uz ukrštanje sa Vac-uzrokovanom tuf-b epidemiologijom i utvrđena kompleksnost tuf-b epidemiologije u kojoj učestvuje i treća genetička linija vektora, H. obsoletus ex Cf, kao i sama biljka dualni domaćin - C. foetida. The cixiid planthopper Hyalesthes obsoletus is generally considered as a polyphagous vector of 'Candidatus (Ca.) P. solani' associated with numerous wild and cultivated plants in central Europe and Mediterranean. Research conducted in southeastern Europe, the distribution centre of H. obsoletus and the area of most 'Ca. P. solani'-inflicted crop diseases, points toward specific dual host-plant associations with: Convolvulus arvensis (Ca), Urtica dioica (Ud), Vitex agnus-castus (Vac) and Crepis foetida (Cf). Population-genetic analysis of mitochondrial and nuclear genetic markers (microsatellites) have revealed cryptic differentiation between sympatric (including syntopic) and geographically distant H. obsoletus populations into three phylogenetic lineages delineated by host-plant preference: 1) Ca-Ud, 2) Vac i 3) Cf. Cryptic species diversification within H. obsoletus sensu lato is supported by the genetic divergence of mitochondrial genes (1.1% - 1.5%), microsatellites that confirm population clustering into three genetic groups associated with specific host-plant (average assignment >90%) and genetic distances among host-associated H. obsoletus metapopulations comparable to the most closely related, morphologically distinguishable species - Hyalesthes thracicus (2.1% - 3.3%). Consequences of the H. obsoletus sensu lato differentiation on the epidemiology of 'Ca. P. solani' are assessed by multilocus genotyping of the phytoplasma isolates detected (1) in situ in natural epidemiological systems of the Mediterranean vineyards and (2) plant inoculation experiments using naturally infected vector populations. Basic 'Ca. P. solani' epidemiological divergence into tuf-a/-ab and tuf-b cycles, each associated with Ud and Ca, respectively, is confirmed with evidences of intermixing Vac-induced tuf-b epidemiology, while complexity of the tuf-b epidemiology is further evidenced through influence of the third genetic lineage of the vector H. obsoletus ex C. foetida and its dual host-plant.

Nutritional symbioses play a central role in the ability of insects to thrive on unbalanced diets and in ensuring their evolutionary success. A genomic model for nutritional symbiosis comprises the hemipteran Acyrthosiphon pisum, and the gamma-3-proteobacterium, Buchnera aphidicola, with genomes encoding highly integrated metabolic pathways. A. pisum feeds exclusively on plant phloem sap, a nutritionally unbalanced diet highly variable in composition, thus raising the question of how this symbiotic system responds to nutritional stress. We addressed this by combining transcriptomic, phenotypic and life history trait analyses to determine the organismal impact of deprivation of tyrosine and phenylalanine. These two aromatic amino acids are essential for aphid development, are synthesized in a metabolic pathway for which the aphid host and the endosymbiont are interdependent, and their concentration can be highly variable in plant phloem sap. We found that this nutritional challenge does not have major phenotypic effects on the pea aphid, except for a limited weight reduction and a 2-day delay in onset of nymph laying. Transcriptomic analyses through aphid development showed a prominent response in bacteriocytes (the core symbiotic tissue which houses the symbionts), but not in gut, thus highlighting the role of bacteriocytes as major modulators of this homeostasis. This response does not involve a direct regulation of tyrosine and phenylalanine biosynthetic pathway and transporter genes. Instead, we observed an extensive transcriptional reprogramming of the bacteriocyte with a rapid down-regulation of genes encoding sugar transporters and genes required for sugar metabolism. Consistently, we observed continued overexpression of the A. pisum homolog of RRAD, a small GTPase implicated in repressing aerobic glycolysis. In addition, we found increased transcription of genes involved in proliferation, cell size control and signaling. We experimentally confirmed the significance of these gene expression changes detecting an increase in bacteriocyte number and cell size in vivo under tyrosine and phenylalanine depletion. Our results support a central role of bacteriocytes in the aphid response to amino acid deprivation: their transcriptional and cellular responses fine-tune host physiology providing the host insect with an effective way to cope with the challenges posed by the variability in composition of phloem sap. ispartof: FRONTIERS IN PHYSIOLOGY vol:9 issue:OCT ispartof: location:Switzerland status: published

First record of the crape myrtle aphid Sarucallis kahawaluokalani (Kirkaldy) and its natural enemies in Guadeloupe (Hemiptera, Aphididae). The aphid Sarucallis kahawaluokalani (Kirkaldy) is recorded for the first time from Guadeloupe and several predator species associated with it are mentioned. All the identified species are illustrated., Le puceron Sarucallis kahawaluokalani (Kirkaldy) est signalé pour la première fois de Guadeloupe et plusieurs espèces de prédateurs qui lui sont associées sont mentionnées. Toutes les espèces identifiées sont illustrées., Étienne Jean, Michel Bruno, Grapin Cyril. Premier signalement du puceron Sarucallis kahawaluokalani (Kirkaldy, 1907) et de ses ennemis naturels en Guadeloupe (Hemiptera, Aphididae). In: Bulletin de la Société entomologique de France, volume 123 (4),2018. pp. 447-450.

Brassicogethes salvan (Audisio et al. Insect Systematics and Evolution, 34, 121) is certainly among the most important and unexpected recent discoveries in the European beetle fauna. The species was initially described from a couple of unidentified specimens collected in 1912 on the Maritime Alps (NW Italy). Despite a long series of attempts to recollect the species at the type locality (Rovina Lake, Mount Argentera Massif, Cuneo Province, Piedmont, NW Italy) and several neighbouring areas of the SW Alps between 2002 and 2016, no specimens of this species were found. We re-discovered B. salvan in a small high valley of the Regional Natural Park of the Maritime Alps, a few dozen kilometers from the type locality. The previously unknown larval host-plant as Descurainia tanacetifolia (L.) Rchb., Brassicaceae was determined. Some unusual life history traits were also observed. In an effort to yield a suitable taxonomic placement for this species, we present a partial preliminary molecular phylogeny for this species and related taxa. A discussion regarding some issues about its actual and potential geographic distribution in southern France and northwestern Italy is also provided. We propose an EN (Endangered) classification for this species following the IUCN criteria, and discuss aspects of its rather problematic conservation biology.

Hyalesthes obsoletus, vektor biljnog patogena 'Candidatus (Ca.) Phytoplasmasolani', smatra se polifagnom štetočinom od ekonomskog značaja u centralnojEvropi i Mediteranu. Istraživanjima sprovedenim u jugoistočnoj Evropi, kojagravitira centru arela vrste i gde je zabeležen značajan broj 'Ca. P. solani'-uslovljenih biljnih bolesti, utvrđeno je postojanje četiri asocijacije vektora sabiljkama dualnim domaćinima: Convolvulus arvensis (Ca), Urtica dioica (Ud), Vitexagnus-castus (Vac) i Crepis foetida (Cf). Populaciono-genetičkim analizamamitohondrijskih i nuklearnih markera (mikrosatelita) utvrđena je kriptičnadiferencijacija simpatričkih (uključujući sintopske) i geografski udaljenih H.obsoletus populacija na tri filogenetičke linije uslovljene biljkom domaćinom: (1)Ca-Ud, (2) Vac i (3) Cf. Pored jasne diferencijacije na mitohondrijskim genima(1.1% - 1.5%) i mikrosatelita koji potvrđuju izdvajanje populacija u jedan od triklastera prema biljci domaćinu (pripadnost >90%), podršku za izdizanje genetičkedivergencije H. obsoletus sensu lato na nivo kriptične specijacije daje registrovanadistanca u odnosu na morfološki najsrodniju vrstu - Hyalesthes thracicus (2.1% -3.3%). Posledice specijalizacije i diferencijacije H. obsoletus sensu lato premabiljkama domaćinima na epidemiologiju 'Ca. P. solani' procenjene su multigenskomkarakterizacijom izolata fitoplazme detektovanih (1) in situ u prirodnimepidemiološkim sistemima mediteranskih vinograda i (2) eksperimentimaunakrsne inokulacije biljaka putem prirodno inficiranih populacija vektora.Potvrđena je osnovna epidemiološka divergencija 'Ca. P. solani' na tuf-a/-ab i tuf-bcikluse vezane za Ud i Ca uz ukrštanje sa Vac-uzrokovanom tuf-b epidemiologijom iutvrđena kompleksnost tuf-b epidemiologije u kojoj učestvuje i treća genetičkalinija vektora, H. obsoletus ex Cf, kao i sama biljka dualni domaćin - C. foetida. The cixiid planthopper Hyalesthes obsoletus is generally considered as apolyphagous vector of 'Candidatus (Ca.) P. solani' associated with numerous wildand cultivated plants in central Europe and Mediterranean. Research conducted insoutheastern Europe, the distribution centre of H. obsoletus and the area of most'Ca. P. solani'-inflicted crop diseases, points toward specific dual host-plantassociations with: Convolvulus arvensis (Ca), Urtica dioica (Ud), Vitex agnus-castus(Vac) and Crepis foetida (Cf). Population-genetic analysis of mitochondrial andnuclear genetic markers (microsatellites) have revealed cryptic differentiationbetween sympatric (including syntopic) and geographically distant H. obsoletuspopulations into three phylogenetic lineages delineated by host-plant preference:1) Ca-Ud, 2) Vac i 3) Cf. Cryptic species diversification within H. obsoletus sensu latois supported by the genetic divergence of mitochondrial genes (1.1% - 1.5%),microsatellites that confirm population clustering into three genetic groupsassociated with specific host-plant (average assignment >90%) and geneticdistances among host-associated H. obsoletus metapopulations comparable to themost closely related, morphologically distinguishable species - Hyalesthes thracicus(2.1% - 3.3%). Consequences of the H. obsoletus sensu lato differentiation on theepidemiology of 'Ca. P. solani' are assessed by multilocus genotyping of thephytoplasma isolates detected (1) in situ in natural epidemiological systems of theMediterranean vineyards and (2) plant inoculation experiments using naturallyinfected vector populations. Basic 'Ca. P. solani' epidemiological divergence intotuf-a/-ab and tuf-b cycles, each associated with Ud and Ca, respectively, isconfirmed with evidences of intermixing Vac-induced tuf-b epidemiology, whilecomplexity of the tuf-b epidemiology is further evidenced through influence of thethird genetic lineage of the vector H. obsoletus ex C. foetida and its dual host-plant.

International audience; The large body of theory on speciation with gene flow has brought to light fundamental differences in the effects of two types of mating rules on speciation: preference/trait rules, in which divergence in both (female) preferences and (male) mating traits is necessary for assortment, and matching rules, in which individuals mate with like individuals on the basis of the presence of traits or alleles that they have in common. These rules can emerge from a variety of behavioral or other mechanisms in ways that are not always obvious. We discuss the theoretical properties of both types of rules and explain why speciation is generally thought to be more likely under matching rather than preference/trait rules. We furthermore discuss whether specific assortative mating mechanisms fall under a preference/trait or matching rule, present empirical evidence for these mechanisms, and propose empirical tests that could distinguish between them. The synthesis of the theoretical literature on these assortative mating rules with empirical studies of the mechanisms by which they act can provide important insights into the occurrence of speciation with gene flow. Finally, by providing a clear framework we hope to inspire greater alignment in the ways that both theoreticians and empiricists study mating rules and how these rules affect speciation through maintaining or eroding barriers to gene flow among closely related species or populations.

International audience; Oceanic islands have been providing important insights on the structuring of ecological communities and, under the context of the present biodiversity crisis, they are paramount to assess the effects of biological invasions on community assembly. In this study we compare the taxonomic and functional diversity of insect herbivore assemblages associated with the dominant tree species of Azorean native forests and investigate the ecological processes that may have originated current patterns of plant-herbivore associations. Five dominant trees—Erica azorica, Ilex perado subsp. azorica, Juniperus brevifolia, Laurus azorica and Vaccinium cylindraceum—were sampled in the remnants of the native forest of Terceira Island (Azores) using a standardised methodology. The taxonomic and functional diversity of insect herbivore assemblages was assessed using complementary metrics and beta diversity partitioning analysis (species replacement and richness differences) aiming to evaluate the variation in insect herbivore assemblages within and between the study plant species. Sixty two insect species, mostly bugs (Hemiptera) and caterpillars (Lepidoptera), were found in the five study plants with indigenous (endemic and native non-endemic) insects occurring with higher species richness and abundance than introduced ones. Species replacement was the most important component of insect herbivore taxonomic beta diversity while differences in trait richness played a major role on functional beta diversity. The endemic E. azorica stands out from the other study plants by having associated a very distinct insect herbivore assemblage with a particular set of functional attributes, mainly composed by large bodied and long shaped species that feed by chewing. Despite the progressive biotic homogenization witnessed in the Azores during the last few decades, several strong associations between the endemic trees and their indigenous insect herbivores remain.

[EN]: Poa trivialis L., a new host-plant for Subhaptomerus frieseri avilai Alonso-Zarazaga, 1983 (Coleoptera, Curculionidae). Subhaptomerus frieseri avilai Alonso Zarazaga, 1983 was described from Luciana (Ciudad Real) on plants from the cabbage family (Brassicaceae). This original host-plant information is discussed, data about a host-plant, Poa trivialis L. (Poaceae), are provided and its distribution is expanded, always within the province of Ciudad Real., [ES]: Subhaptomerus frieseri avilai Alonso Zarazaga, 1983 fue descrito de Luciana (Ciudad Real) sobre crucíferas (Brassicaceae). Se discute la corrección de este último dato, se aporta información sobre la planta nutricia, Poa trivialis L. (Poaceae) y se amplía su distribución, siempre dentro de la provincia de Ciudad Real.

Herbivore-induced plant volatiles are often involved in direct and indirect plant defence against herbivores. Linalool is a common floral scent and found to be released from leaves by many plants after herbivore attack. In this study, a linalool/nerolidol synthase, FaNES1, was overexpressed in the plastids of chrysanthemum plants (Chrysanthemum morifolium). The volatiles of FaNES1 chrysanthemum leaves were strongly dominated by linalool, but they also emitted small amount of the C11-homoterpene, (3E)-4,8-dimethyl-1,3,7-nonatriene, a derivative of nerolidol. Four nonvolatile linalool glycosides in methanolic extracts were found to be significantly increased in the leaves of FaNES1 plants compared to wild-type plants. They were putatively identified by LC-MS-MS as two linalool-malonyl-hexoses, a linalool-pentose-hexose and a glycoside of hydroxy-linalool. A leaf-disc dual-choice assay with western flower thrips (WFT, Frankliniella occidentalis) showed, initially during the first 15 min of WFT release, that FaNES1 plants were significantly preferred. This gradually reversed into significant preference for the control, however, at 20-28 h after WFT release. The initial preference was shown to be based on the linalool odour of FaNES1 plants by olfactory dual-choice assays using paper discs emitting pure linalool at similar rates as leaf discs. The reversal of preference into deterrence could be explained by the initial nonvolatile composition of the FaNES1 plants, as methanolic extracts were less preferred by WFT. Considering the common occurrence of linalool and its glycosides in plant tissues, it suggests that plants may balance attractive fragrance with 'poor taste' using the same precursor compound.

The effects of plant competition for light on the emission of plant volatile organic compounds (VOCs) were studied by investigating how different light qualities that occur in dense vegetation affect the emission of constitutive and methyl-jasmonate-induced VOCs. Arabidopsis thaliana Columbia (Col-0) plants and Pieris brassicae caterpillars were used as a biological system to study the effects of light quality manipulations on VOC emissions and attraction of herbivores. VOCs were analysed using gas chromatography-mass spectrometry and the effects of light quality, notably the red : far red light ratio (R : FR), on expression of genes associated with VOC production were studied using reverse transcriptase-quantitative PCR. The emissions of both constitutive and methyl-jasmonate-induced green leaf volatiles and terpenoids were partially suppressed under low R : FR and severe shading conditions. Accordingly, the VOC-based preference of neonates of the specialist lepidopteran herbivore P. brassicae was significantly affected by the R : FR ratio. We conclude that VOC-mediated interactions among plants and between plants and organisms at higher trophic levels probably depend on light alterations caused by nearby vegetation. Studies on plant-plant and plant-insect interactions through VOCs should take into account the light quality within dense stands when extrapolating to natural and agricultural field conditions.

Although numerous adults of the buprestid genus Steraspis Dejean, 1833, have been captured in West Africa, little is known about the biology of the known species, especially about their immature stages. The objective of the present field observations was to increase the knowledge on the biology of a common but localized species in Benin. In early 2012, a field survey was conducted to search for the immature stages of Steraspis species, especially S. fastuosa Gerstaecker, 1871. In May 2012, a nymph of S. fastuosa was found within the taproot of Acacia hockii De Wild (Fabaceae) and also an adult of the same species within the taproot of a nearby A. hockii. This welldeveloped adult was found at 7 cm below the soil surface and ready to emerge from the taproot. Prior to pupation, the mature larva had cut along the collar of the taproot, thus facilitating the emergence of the adult. This is the first report on the developmental biology of this species in West Africa., À propos de la biologie de Steraspis fastuosa Gerstaecker dans l’Atacora (nord Bénin) (Coleoptera, Buprestidae). Bien que de nombreux adultes du genre Steraspis Dejean, 1833, aient été capturés en Afrique de l’Ouest, il existe peu d’information sur la biologie des espèces, spécialement concernant leurs stades préimaginaux. L’objectif du présent travail était d’améliorer la connaissance de la biologie d’une espèce commune, mais localisée, au Bénin. Début 2012, un travail de terrain a été conduit pour rechercher la larve de S. fastuosa Gerstaecker, 1871. Ainsi, en mai 2012, nous avons pu trouver une nymphe de S. fastuosa dans la racine principale d’un Acacia hockii De Wild (Fabaceae) ainsi qu’un adulte de S. fastuosa dans le pivot d’un autre A. hockii voisin. L’adulte était parfaitement formé avec les élytres durcis. Il était situé à 7 cm sous la surface du sol et prêt à quitter le pivot de l’arbre. La larve avait foré un trou ellipsoïde au niveau du collet de l’arbre puis l’avait garni de débris de bois compacté, ce qui facilite la sortie de l’imago du pivot. C’est la première observation concernant la biologie de cette espèce en Afrique de l’Ouest., Vayssières Jean-François, Bellamy Charles L., Goergen Georg, Adandonon Appolinaire, Sinzogan Antonio, Curletti Gianfranco. About the biology of Steraspis fastuosa Gerstaecker in Atacora region, northern Benin (Coleoptera, Buprestidae). In: Bulletin de la Société entomologique de France, volume 118 (4),2013. pp. 427-432.

Summary 1. In their natural environment, plants are faced with a multitude of attackers, of which insect herbivores and plant pathogens are an important component. In response to these attacks, plants release volatile organic compounds (VOCs), which play an important role in the communication between plants and the associated community members, such as other herbivores, phytopathogens and the natural enemies of herbivores. 2. While numerous studies have focused on either plant–pathogen or plant–insect interactions, less is known when these two sets of interactions co-occur. Depending on the mode of attack of the pathogen (necrotroph vs. biotroph) or herbivore (chewing vs. piercing-sucking) they will activate different defence pathways in the plant in which the phytohormones salicylic acid (SA), jasmonic acid (JA) and ethylene (ET) play key roles. As these pathways can crosstalk, a pathogen infection can interfere in a plant’s defence response to herbivory, and vice versa. 3. Infestation of a plant with organisms inducing SA signalling prior to – or simultaneously with – attack by organisms that induce the JA pathway often suppresses JA signalling. However, the impact of this signalling pathway crosstalk on VOC induction is not clear cut, as there is high variability in the effects on volatile emissions, ranging from suppression to enhanced emission. The effects of the modified volatile blends on the foraging success of carnivorous natural enemies of herbivorous insects have started to be investigated. Foraging success of natural enemies generally withstands this modification of the host-induced VOC blend, but the presence or absence of key compounds is an important determinant of the response of certain carnivores. 4. Further studies incorporating plant–insect and plant–pathogen interactions at different levels of biological integration will provide valuable insight in how plants integrate signals from different suites of attacking organisms into an adaptive defence response.

The importance of trans-generational effects in shaping an individuals' phenotype and fitness, and consequently even impacting population dynamics is increasingly apparent. Most of the research on trans-generational effects still focuses on plants, mammals, and birds. In the past few years, however, increasing number of studies, especially on maternal effects, have highlighted their importance also in many insect systems. Lepidoptera, specifically butterflies, have been used as model systems for studying the role of phenotypic plasticity within generations. As ectotherms, they are highly sensitive to environmental variation, and indeed many butterflies show adaptive phenotypic plasticity in response to environmental conditions. Here, we synthesize what is known about trans-generational effects in Lepidoptera, compile evidence for different environmental cues that are important drivers of trans-generational effects, and point out which offspring traits are mainly impacted. Finally, we emphasize directions for future research that are needed for better understanding of the adaptive nature of trans-generational effects in Lepidoptera in particular, but potentially also in other organisms.

The chemoreception response of an aphidophagous coccinellid predators [Hippodamia variegate (Goeze, 1777) (Coleoptera: Coccinellidae)] to the odors from four different synthetic HIPVs [methyl salicylate (MeSA), (E)-2-hexenal (E(2)H), farnesene (F) and benzaldehyde (Be)] was tested using two different doses (0.001 and 1 g/L) of the HIPVs, both alone and in five binary combinations [MeSA+F, MeSA+E(2)H, MeSA+Be, E(2)H+F and Be+F]. Insect responses were evaluated using two-choice experiments with a Y-tube olfactometer in laboratory conditions. The low single dose of MeSA attracted significantly more adults of H. variegata (71%) towards tubes containing the volatile source compared with the control volatile containing pure n-hexane. Adults of H. variegata did not significantly prefer single forms of either Be, E(2)H or F compared with MeSA alone. Additionally, this study showed that binary blends of MeSA with Be or F had significantly more attractiveness for H. variegata adults than controls. Thus, the compounds, Be and F, used together with MeSA were observed to increase adult attraction. In the future, additional studies that monitor the preferences of field populations of these predators treated with the attractive HIPV combinations should be conducted to confirm these findings., Yaprakbiti avcısı coccinellid türü Hippodamia variegata (Goeze, 1777) (Coleoptera: Coccinellidae)’nın zararlılar tarafından teşvik edilen (HIPV) kokularının dört farklı sentetik formunun [methyl salicylate (MeSA), (E)-2-hexenal (E(2)H), farnesene (F) ve benzaldehyde (Be)] tek başına ve ikili kombinasyonlarının [MeSA+F, MeSA+E(2)H, MeSA+Be, E(2)H+F ve Be+F] iki farklı dozuna (0.001 ve 1 g/L) olan kimyasal algılama cevapları test edilmiştir. Böceğin cevapları laboratuvar koşullarında iki seçenekli Y-tüp olfaktometre ile değerlendirilmiştir. Kontrol olarak kullanılan saf hekzana göre, MeSA’nın düşük dozu önemli bir şekilde daha fazla H. variegata erginini (%71) cezbetmiştir. Ayrıca, H. variegata erginleri Be, E(2)H ve F’nin tekli kombinasyonları ile önemli düzeyde cezbedilememiştir. Diğer taraftan, MeSA’nın Be ve F ile ikili kombinasyonlarının kontrole göre önemli bir şekilde daha fazla H. variegata dişisini çektiği belirlenmiştir. Sonuç olarak, bu bileşikler (Be ve F) MeSA ile birlikte kullanıldığında erginlerin cezbedilmesini arttırmışlardır. Gelecekte, bu bulguların desteklenmesi için bu avcı böceğin arazi koşullarında cezbedildiği kokulara yöneliminin izleneceği ek çalışmaların yapılması gerekmektedir.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; To determine to what extent wild species related to crops might serve as refuges for insect pests and their natural enemies, we compared the performance of the aphid Myzus persicae and its endoparasitoid Diaeretiella rapae on one cultivar of Brassica napus and Brassica oleracea, two wild species Brassica nigra and Sinapis arvensis, and one cultivar of Solanum lycopersicum. These species differ in traits associated with plant defences that may have an impact on the herbivore and its parasitoid. In contrast to our initial hypothesis, aphid population growth rate was significantly smaller on B. napus than on the other Brassicaceae species. Similarly, the performance of the parasitoid was affected by the host plant on which the aphid was feeding. However, aphid and parasitoid performance was not correlated. Thus, in temporally changing landscapes, pests and natural enemies may utilize crops and wild-related host species with contrasting impacts on their fitness.

The performance of natural enemies, such as parasitoid wasps, is affected by differences in the quality of the host’s diet, frequently mediated by species or population-related differences in plant allelochemistry. Here, we compared survival, development time, and body mass in a generalist herbivore, the cabbage moth, Mamestra brassicae, and its solitary endoparasitoid, Microplitis mediator, when reared on two cultivated (CYR and STH) and three wild (KIM, OH, and WIN) populations of cabbage, Brassica oleracea. Plants either were undamaged or induced by feeding of larvae of the cabbage butterfly, Pieris rapae. Development and biomass of M. brassicae and Mi. mediator were similar on both cultivated and one wild cabbage population (KIM), intermediate on the OH population, and significantly lower on the WIN population. Moreover, development was prolonged and biomass was reduced on herbivore-induced plants. However, only the survival of parasitized hosts (and not that of healthy larvae) was affected by induction. Analysis of glucosinolates in leaves of the cabbages revealed higher levels in the wild populations than cultivars, with the highest concentrations in WIN plants. Multivariate statistics revealed a negative correlation between insect performance and total levels of glucosinolates (GS) and levels of 3-butenyl GS. However, GS chemistry could not explain the reduced performance on induced plants since only indole GS concentrations increased in response to herbivory, which did not affect insect performance based on multivariate statistics. This result suggests that, in addition to aliphatic GS, other non- GS chemicals are responsible for the decline in insect performance, and that these chemicals affect the parasitoid more strongly than the host. Remarkably, when developing on WIN plants, the survival of Mi. mediator to adult eclosion was much higher than in its host, M. brassicae. This may be due to the fact that hosts parasitized by Mi. mediator pass through fewer instars, and host growth is arrested when they are only a fraction of the size of healthy caterpillars. Certain aspects of the biology and life-history of the host and parasitoid may determine their response to chemical challenges imposed by the food plant.

1. Plant resistance against herbivores can act directly (e.g. by producing toxins) and indirectly (e.g. by attracting natural enemies of herbivores). If plant secondary metabolites that cause direct resistance against herbivores, such as glucosinolates, negatively influence natural enemies, this may result in a conflict between direct and indirect plant resistance. 2. Our objectives were (i) to test herbivore-mediated effects of glucosinolates on the performance of two generalist predators, the marmalade hoverfly (Episyrphus balteatus) and the common green lacewing (Chrysoperla carnea) and (ii) to test whether intraspecific plant variation affects predator performance. 3. Predators were fed either Brevicoryne brassicae, a glucosinolate-sequestering specialist aphid that contains aphid-specific myrosinases, or Myzus persicae, a non-sequestering generalist aphid that excretes glucosinolates in the honeydew, reared on four different white cabbage cultivars. Predator performance and glucosinolate concentrations and profiles in B. brassicae and host-plant phloem were measured, a novel approach as previous studies often measured glucosinolate concentrations only in total leaf material. 4. Interestingly, the specialist aphid B. brassicae selectively sequestered glucosinolates from its host plant. The performance of predators fed this aphid species was lower than when fed M. persicae. When fed B. brassicae reared on different cultivars, differences in predator performance matched differences in glucosinolate profiles among the aphids. 5. We show that not only the prey species, but also the plant cultivar can have an effect on the performance of predators. Our results suggest that in the tritrophic system tested, there might be a conflict between direct and indirect plant resistance

A central issue in the evolutionary ecology of species interactions is coevolution, which involves the reciprocal selection between individuals of interacting species. Understanding the importance of coevolution in shaping species interactions requires the consideration of spatial variation in their strength. This is exactly what the, recently developed, geographic mosaic theory of coevolution addresses. Another major development in the study of population ecology is the introduction of the population genomics approach in this field of research. This approach addresses spatial processes through molecular methods. It is of particular interest that population genomics is especially applicable to natural populations of non-model species. We describe how population genomics can be used in the context of the geographic mosaic of coevolution, specifically to identify coevolutionary hot-spots, and to attribute genetic variation found at specific loci to processes of selection versus trait remixing. The proposed integration of the population genomics approach with the conceptual framework of the geographic mosaic of coevolution is illustrated with a few selected, particularly demonstrative, examples from the realm of insect--plant interactions.

The indirect defense mechanisms of plants comprise the production of herbivore-induced plant volatiles that can attract natural enemies of plant attackers. One of the often emitted compounds after herbivory is methyl salicylate (MeSA). Here, we studied the importance of this caterpillar-induced compound in the attraction of the parasitoid wasp Diadegma semiclausum by using a mutant Arabidopsis line. Pieris rapae infested AtBSMT1-KO mutant Arabidopsis plants, compromised in the biosynthesis of MeSA, were more attractive to parasitoids than infested wild-type plants. This suggests that the presence of MeSA has negative effects on parasitoid host-finding behavior when exposed to wild-type production of herbivore-induced Arabidopsis volatiles. Furthermore, in line with this, we recorded a positive correlation between MeSA dose and repellence of D. semiclausum when supplementing the headspace of caterpillar-infested AtBSMT1-KO plants with synthetic MeSA. Electronic supplementary material The online version of this article (doi:10.1007/s10886-010-9787-1) contains supplementary material, which is available to authorized users.

The Bruchidius albopubens (Pic) species-group : definition, description of new species and biological data (Coleoptera, Chrysomelidae, Bruchinae). The species-group Bruchidius albopubens (Pic) is created for B. albopubens, widespread in Africa south of the Sahara and in southern Asia, B. medaniensis (Decelle), until now known only from Sudan, also present in Kenya, as well as two new species : B. umbratus from the Comoros, and B. watamuensis from Kenya. These Seed Beetles seem strongly associated with tribe Indigoferae (Leguminosae, Fabaceae) : the larva of B. watamuensis develops in the seeds of Indigofera trita var. subulata (Vahl ex Poir.) Ali, whereas that of B. albopubens feeds in the seeds of four Indigofera species and in those of Cyamopsis tetragonoloba (L.) Taub., also an Indigofereae., Le groupe d''espèces Bruchidius albopubens (Pic) est créé pour B. albopubens, répandu dans une grande partie de l''Afrique sub-saharienne et en Asie du sud, B. medaniensis (Decelle), connu jusqu''ici du Soudan mais existant aussi au Kenya, ainsi que pour deux espèces nouvelles : B. umbratus des Comores et B. watamuensis du Kenya. Ces Bruches semblent étroitement liées à la tribu des Indigofereae (Légumineuses, Fabaceae) : la larve de B. watamuensis se développe dans les graines d''Indigofera trita var. subulata (Vahl ex Poir.) Ali, tandis que celle de B. albopubens se nourrit des graines de quatre espèces d''Indigofera et de celles de Cyamopsis tetragonoloba (L.) Taub., également une Indigofereae., Delobel Alex, Le Rü Bruno P. Le groupe d’espèces Bruchidius albopubens (Pic) : définition, description d’espèces nouvelles et données biologiques (Coleoptera, Chrysomelidae, Bruchinae). In: Bulletin de la Société entomologique de France, volume 115 (1),2010. pp. 23-29.

Behavioral and electrophysiological responses of larvae of the polyphagous moth species Helicoverpa armigera to two plant-derived allelochemicals were studied, both in larvae that had been reared on a diet devoid of these compounds and in larvae previously exposed to these compounds. In dual-choice cotton leaf disk and pepper fruit disk arena assays, caterpillars reared on a normal artificial diet were strongly deterred by strychnine and strophanthin- K. However, caterpillars reared on an artificial diet containing strychnine were insensitive to strychnine and strophanthin-K. Similarly, caterpillars reared on an artificial diet containing strophanthin-K were also desensitized to both deterrent chemicals. Electrophysiological tests revealed that the deterrent-sensitive neurons in taste sensilla on the maxillae of caterpillars reared on each deterrent- containing diet displayed reduced sensitivity to the two chemicals compared with the caterpillars reared on normal diets. We conclude that the experience-dependent behavioral plasticity was partly based on the reduced sensitivity of taste receptor neurons and that the desensitization of taste receptor neurons contributed to the crosshabituation to the two chemicals.