- G. Bukovinszkine-Kiss (1)
- T. Bukovinszky (1)
- N.M. Dam van (2)
- M. Dicke (11)
- H. Dijkman (1)
- E. Donk van (1)
- N.E. Fatouros (2)
- C.S. Gold (1)
- G.J.Z. Gols (1)
- R. Gols (1)
- J.A. Harvey (1)
- C.H.R. Heip (1)
- M. Hilker (1)
- K.M. Hoedjes (2)
- C.A. Hordijk (2)
- M.E. Huigens (2)
- A. Huis van (1)
- J.J. Jansen (1)
- P.W. Jong de (1)
- L. Kang (1)
- I.F. Kappers (1)
- N. Li (1)
- S.S. Liu (1)
- J.J.A. Loon van (4)
- D. Lucas Gomes Marques Barbosa (1)
- T.R. Menzel (1)
- P. Mercke (1)
- J.J. Middelburg (1)
- W.M. Mooij (1)
- R. Mumm (1)
- M.J. Müller (1)
- F.G. Pashalidou (1)
- E.H. Poelman (1)
- M.A. Posthumus (2)
- W.H. Putten van der (1)
- B.L. Qiu (2)
- M. Roosjen (1)
- E.G.W.M. Schijlen (1)
- J.P. Shu (1)
- H.M. Smid (3)
- T.A.L. Snoeren (1)
- W. Tinzaara (1)
- F.W.A. Verstappen (1)
- L.E.M. Vet (5)
- O.F.J. Vorst (1)
- M. Vos (1)
- J.J.F.A. Vugt van (1)
- F.L. Wackers (1)
- J. Wei (1)
- J.H. Werren (1)
- J.B. Woelke (1)
- P.J. Zhang (1)
Learning-induced gene expression in the heads of two Nasonia species that differ in long-term memory formation
Hoedjes, K.M. ; Smid, H.M. ; Schijlen, E.G.W.M. ; Vet, L.E.M. ; Vugt, J.J.F.A. van - \ 2015
BMC Genomics 16 (2015). - ISSN 1471-2164
natural variation - antisense transcription - protein-synthesis - foraging success - parasitic wasps - drosophila - vitripennis - pathway - consolidation - opportunities
Background Cellular processes underlying memory formation are evolutionary conserved, but natural variation in memory dynamics between animal species or populations is common. The genetic basis of this fascinating phenomenon is poorly understood. Closely related species of Nasonia parasitic wasps differ in long-term memory (LTM) formation: N. vitripennis will form transcription-dependent LTM after a single conditioning trial, whereas the closely-related species N. giraulti will not. Genes that were differentially expressed (DE) after conditioning in N. vitripennis, but not in N. giraulti, were identified as candidate genes that may regulate LTM formation. Results RNA was collected from heads of both species before and immediately, 4 or 24 hours after conditioning, with 3 replicates per time point. It was sequenced strand-specifically, which allows distinguishing sense from antisense transcripts and improves the quality of expression analyses. We determined conditioning-induced DE compared to naïve controls for both species. These expression patterns were then analysed with GO enrichment analyses for each species and time point, which demonstrated an enrichment of signalling-related genes immediately after conditioning in N. vitripennis only. Analyses of known LTM genes and genes with an opposing expression pattern between the two species revealed additional candidate genes for the difference in LTM formation. These include genes from various signalling cascades, including several members of the Ras and PI3 kinase signalling pathways, and glutamate receptors. Interestingly, several other known LTM genes were exclusively differentially expressed in N. giraulti, which may indicate an LTM-inhibitory mechanism. Among the DE transcripts were also antisense transcripts. Furthermore, antisense transcripts aligning to a number of known memory genes were detected, which may have a role in regulating these genes. Conclusion This study is the first to describe and compare expression patterns of both protein-coding and antisense transcripts, at different time points after conditioning, of two closely related animal species that differ in LTM formation. Several candidate genes that may regulate differences in LTM have been identified. This transcriptome analysis is a valuable resource for future in-depth studies to elucidate the role of candidate genes and antisense transcription in natural variation in LTM formation.
Introgression study reveals two quantitative trait loci involved in interspecific variation in memory retention among Nasonia wasp species
Hoedjes, K.M. ; Smid, H.M. ; Vet, L.E.M. ; Werren, J.H. - \ 2014
Heredity 113 (2014). - ISSN 0018-067X - p. 542 - 550.
long-term-memory - natural variation - parasitic wasps - learning rate - drosophila - evolution - consolidation - dynamics - pteromalidae - hymenoptera
Genes involved in the process of memory formation have been studied intensively in model organisms; however, little is known about the mechanisms that are responsible for natural variation in memory dynamics. There is substantial variation in memory retention among closely related species in the parasitic wasp genus Nasonia. After a single olfactory conditioning trial, N. vitripennis consolidates long-term memory that lasts at least 6 days. Memory of the closely related species N. giraulti is present at 24¿h but is lost within 2 days after a single trial. The genetic basis of this interspecific difference in memory retention was studied in a backcrossing experiment in which the phenotype of N. giraulti was selected for in the background of N. vitripennis for up to five generations. A genotyping microarray revealed five regions that were retained in wasps with decreased memory retention. Independent introgressions of individual candidate regions were created using linked molecular markers and tested for memory retention. One region on chromosome 1 (spanning ~5.8¿cM) and another on chromosome 5 (spanning ~25.6¿cM) resulted in decreased memory after 72¿h, without affecting 24-h-memory retention. This phenotype was observed in both heterozygous and homozygous individuals. Transcription factor CCAAT/enhancer-binding protein and a dopamine receptor, both with a known function in memory formation, are within these genomic regions and are candidates for the regulation of memory retention. Concluding, this study demonstrates a powerful approach to study variation in memory retention and provides a basis for future research on its genetic basis.
Reciprocal crosstalk between jasmonate and salicylate defence-signalling pathways modulates plant volatile emission and herbivore host-selection behaviour
Wei, J. ; Loon, J.J.A. van; Gols, R. ; Menzel, T.R. ; Li, N. ; Kang, L. ; Dicke, M. - \ 2014
Journal of Experimental Botany 65 (2014)12. - ISSN 0022-0957 - p. 3289 - 3298.
mediated interactions - specialist herbivore - tetranychus-urticae - induced resistance - parasitic wasps - cotton plants - spider-mites - insect - acid - pathogen
The jasmonic acid (JA) and salicylic acid (SA) signalling pathways, which mediate induced plant defence responses, can express negative crosstalk. Limited knowledge is available on the effects of this crosstalk on host-plant selection behaviour of herbivores. We report on temporal and dosage effects of such crosstalk on host preference and oviposition-site selection behaviour of the herbivorous spider mite Tetranychus urticae towards Lima bean (Phaseolus lunatus) plants, including underlying mechanisms. Behavioural observations reveal a dynamic temporal response of mites to single or combined applications of JA and SA to the plant, including attraction and repellence, and an antagonistic interaction between SA- and JA-mediated plant responses. Dose-response experiments show that concentrations of 0.001mM and higher of one phytohormone can neutralize the repellent effect of a 1mM application of the other phytohormone on herbivore behaviour. Moreover, antagonism between the two signal-transduction pathways affects phytohormone-induced volatile emission. Our multidisciplinary study reveals the dynamic plant phenotype that is modulated by subtle changes in relative phytohormonal titres and consequences for the dynamic host-plant selection by an herbivore. The longer-term effects on plant–herbivore interactions deserve further investigation.
Root and shoot jasmonic acid induction differently affects the foraging behavior of under semi-field conditions
Qiu, B.L. ; Dam, N.M. van; Harvey, J.A. ; Vet, L.E.M. - \ 2012
BioControl 57 (2012). - ISSN 1386-6141 - p. 387 - 395.
induced plant volatiles - planthopper nilaparvata-lugens - carnivorous arthropods - anagrus-nilaparvatae - pieris-brassicae - beta-glucosidase - infochemical use - parasitic wasps - rice volatiles - zea-mays
Plants can accumulate and release defensive chemicals by activating various signaling pathways when they are damaged by herbivores or pathogens. The jasmonic acid pathway is activated after damage by chewing herbivores. Here we used jasmonic acid (JA) as an exogenous elicitor to induce feral cabbage plants. In this study, the effects of root JA (RJA) and shoot JA (SJA) induction on the foraging behavior of , a parasitoid of the large cabbage white butterfly , was investigated under semi-field conditions. In all combinations of differently induced plants (RJA, SJA and control plants), the percentages of shoot induced plants that were visited by at least one wasp were significantly higher than those of controls or root induced plants during 3 h of foraging. Consequently, parasitism rates of on shoot-JA induced plants were significantly higher than on plants induced with JA to the roots or control plants in all tests. However, this behavioral preference was not reflected in the allocation of offspring. The clutch sizes of eggs on control, root induced and shoot induced plants were not significantly different from each other in two-choice or three-choice experiments, but did differ with clutch size in the two-choice experiment of uninduced control plants versus SJA. This semi-field study helps to further understand the choice behavior and preferences of parasitoids in natural multitrophic communities in which plants induced with root or shoot herbivores occur together.
The effects of herbivore-induced plant volatiles on interactions between plants and flower-visiting insects
Lucas Gomes Marques Barbosa, D. ; Loon, J.J.A. van; Dicke, M. - \ 2011
Phytochemistry 72 (2011)13. - ISSN 0031-9422 - p. 1647 - 1654.
floral scent - leaf herbivory - multitrophic interactions - nicotiana-attenuata - natural-selection - indirect defenses - isomeris-arborea - parasitic wasps - cotton plants - wild radish
Plants are faced with a trade-off between on the one hand growth, development and reproduction and on the other hand defence against environmental stresses. Yet, research on insect–plant interactions has addressed plant–pollinator interactions and plant–attacker interactions separately. Plants have evolved a high diversity of constitutive and induced responses to attack, including the systemic emission of herbivore-induced plant volatiles (HIPVs). The effect of HIPVs on the behaviour of carnivorous insects has received ample attention for leaf-feeding (folivorous) species and their parasitoids and predators. Here, we review whether and to what extent HIPVs affect the interaction of plants in the flowering stage with mutualistic and antagonistic insects. Whereas the role of flower volatiles in the interactions between plants and insect pollinators has received increased attention over the last decade, studies addressing both HIPVs and pollinator behaviour are rare, despite the fact that in a number of plant species herbivory is known to affect flower traits, including size, nectar secretion and composition. In addition, folivory and florivory can also result in significant changes in flower volatile emission and in most systems investigated, pollinator visitation decreased, although exceptions have been found. Negative effects of HIPVs on pollinator visitation rates likely exert negative selection pressure on HIPV emission. The systemic nature of herbivore-induced plant responses and the behavioural responses of antagonistic and mutualistic insects, requires the study of volatile emission of entire plants in the flowering stage. We conclude that approaches to integrate the study of plant defences and pollination are essential to advance plant biology, in particular in the context of the trade-off between defence and growth/reproduction
Identification of Biologically Relevant Compounds in Aboveground and Belowground Induced Volatile Blends
Dam, N.M. van; Qiu, B.L. ; Hordijk, C.A. ; Vet, L.E.M. ; Jansen, J.J. - \ 2010
Journal of Chemical Ecology 36 (2010)9. - ISSN 0098-0331 - p. 1006 - 1016.
herbivore-induced volatiles - partial least-squares - jasmonic acid - specialist herbivore - cotesia-glomerata - parasitic wasps - natural enemies - plants - root - performance
Plants under attack by aboveground herbivores emit complex blends of volatile organic compounds (VOCs). Specific compounds in these blends are used by parasitic wasps to find their hosts. Belowground induction causes shifts in the composition of aboveground induced VOC blends, which affect the preference of parasitic wasps. To identify which of the many volatiles in the complex VOC blends may explain parasitoid preference poses a challenge to ecologists. Here, we present a case study in which we use a novel bioinformatics approach to identify biologically relevant differences between VOC blends of feral cabbage (Brassica oleracea L.). The plants were induced aboveground or belowground with jasmonic acid (JA) and shoot feeding caterpillars (Pieris brassicae or P. rapae). We used Partial Least Squares--Discriminant Analysis (PLSDA) to integrate and visualize the relation between plant-emitted VOCs and the preference of female Cotesia glomerata. Overall, female wasps preferred JA-induced plants over controls, but they strongly preferred aboveground JA-induced plants over belowground JA-induced plants. PLSDA revealed that the emission of several monoterpenes was enhanced similarly in all JA-treated plants, whereas homoterpenes and sesquiterpenes increased exclusively in aboveground JA-induced plants. Wasps may use the ratio between these two classes of terpenes to discriminate between aboveground and belowground induced plants. Additionally, it shows that aboveground applied JA induces different VOC biosynthetic pathways than JA applied to the root. Our bioinformatic approach, thus, successfully identified which VOCs matched the preferences of the wasps in the various choice tests. Additionally, the analysis generated novel hypotheses about the role of JA as a signaling compound in aboveground and belowground induced responses in plants
Chemical espionage on species-specific butterfly anti-aphrodisiacs by hitchhiking Trichogramma wasps
Huigens, M.E. ; Woelke, J.B. ; Pashalidou, F.G. ; Bukovinszky, T. ; Smid, H.M. ; Fatouros, N.E. - \ 2010
Behavioral Ecology 21 (2010). - ISSN 1045-2249 - p. 470 - 478.
podisus-maculiventris hemiptera - weevil ceutorhynchus-assimilis - rape brassica-napus - sex-pheromone - oilseed rape - entomophagous insects - parasitic wasps - egg parasitoids - foraging behavior - infochemical use
Parasitic wasps employ a wide range of chemical cues to find their hosts. Very recently, we discovered how 2 closely related egg parasitoids, Trichogramma brassicae and Trichogramma evanescens, exploit the anti-aphrodisiac pheromone benzyl cyanide of one of their hosts, the gregarious large cabbage white butterfly Pieris brassicae that deposits a clutch of more than 20 eggs per oviposition bout. The pheromone is transferred by male butterflies to females during mating to enforce female monogamy. On detecting the anti-aphrodisiac, the tiny parasitic wasps ride on a mated female butterfly to a host plant and then parasitize her freshly laid eggs. The present study demonstrates that both wasp species similarly exploit the anti-aphrodisiac mixture of methyl salicylate and indole of another host, the more common solitary small cabbage white butterfly Pieris rapae that deposits only one egg at a time. Interestingly, this behavior is innate in T. brassicae, whereas T. evanescens learns it after one successful ride on a mated female butterfly. Moreover, we show that the wasps only respond to the anti-aphrodisiacs of the 2 cabbage white butterflies when the ubiquitous compounds are part of a complete mated female odor blend. Obviously, parasitic wasps use the sophisticated espionage-and-ride strategy to find eggs of different gregarious and solitary host species. From the wasps’ perspective there seems to be a trade-off between the abundance and egg-laying behavior of the butterflies. Our findings suggest that Pieris butterflies are under strong selective pressure to minimize the use of an anti-aphrodisiac.
Different headspace profiles in wild crucifer species in response to Plutella xylostella herbivory and exogenous jasmonic acid application
Zhang, P.J. ; Shu, J.P. ; Dicke, M. ; Liu, S.S. - \ 2010
Insect Science 17 (2010)1. - ISSN 1672-9609 - p. 29 - 37.
plant volatiles - nicotiana-attenuata - arabidopsis-thaliana - indirect defenses - methyl jasmonate - parasitic wasps - identification - involvement - emissions - elicitor
Although exogenous treatment of plants with jasmonic acid (JA) may result in induced responses similar to plant defences induced by herbivory, few studies have compared the details of insect herbivory and JA-mimicked responses. We compared volatiles of two crucifer species, Cardamine impatiens and Lepidium virginicum, in response to Plutella xylostella larval feeding and exogenous application of JA, over the entire period of time when induced changes were detectable. Significant differences in the composition and timing of volatiles occurred between herbivory and JA treatments in both plants. The quantity of nitrile and isothiocyanate released in response to herbivory was significantly larger than that upon JA treatment. In each of the two plant species, most volatile components were emitted immediately upon larval feeding and their quantity dropped rapidly once feeding ceased. In contrast, the emission of volatiles in response to JA treatment lasted for a longer period of time, and the maximum emission rate was recorded 2 and 3 days after JA treatment in L. virginicum and C. impatiens respectively. These findings are discussed in the context of signal-transduction pathways and mechanisms involved in induced emissions of plant volatiles, as well as induced defences mediated by plant volatiles
Inhibition of lipoxygenase affects induction of both direct and indirect plant defences against herbivorous insects
Bruinsma, M. ; Broekhoven, S. ; Poelman, E.H. ; Posthumus, M.A. ; Müller, M.J. ; Loon, J.J.A. van; Dicke, M. - \ 2010
Oecologia 162 (2010)2. - ISSN 0029-8549 - p. 393 - 404.
volatile biosynthesis - oviposition preference - differential induction - tritrophic interaction - arabidopsis-thaliana - nicotiana-attenuata - parasitic wasps - specialist - responses - arthropods
Herbivore-induced plant defences influence the behaviour of insects associated with the plant. For biting–chewing herbivores the octadecanoid signal-transduction pathway has been suggested to play a key role in induced plant defence. To test this hypothesis in our plant—herbivore—parasitoid tritrophic system, we used phenidone, an inhibitor of the enzyme lipoxygenase (LOX), that catalyses the initial step in the octadecanoid pathway. Phenidone treatment of Brussels sprouts plants reduced the accumulation of internal signalling compounds in the octadecanoid pathway downstream of the step catalysed by LOX, i.e. 12-oxo-phytodienoic acid (OPDA) and jasmonic acid. The attraction of Cotesia glomerata parasitoids to host-infested plants was significantly reduced by phenidone treatment. The three herbivores investigated, i.e. the specialists Plutella xylostella, Pieris brassicae and Pieris rapae, showed different oviposition preferences for intact and infested plants, and for two species their preference for either intact or infested plants was shown to be LOX dependent. Our results show that phenidone inhibits the LOX-dependent defence response of the plant and that this inhibition can influence the behaviour of members of the associated insect community.
Male-derived butterfly anti-aphrodisiac mediates induced indirect plant defense
Fatouros, N.E. ; Broekgaarden, C. ; Bukovinszkine-Kiss, G. ; Loon, J.J.A. van; Mumm, R. ; Huigens, M.E. ; Dicke, M. ; Hilker, M. - \ 2008
Proceedings of the National Academy of Sciences of the United States of America 105 (2008). - ISSN 0027-8424 - p. 10033 - 10038.
parasitic wasps - pierid butterflies - oral secretions - gene-expression - host location - atp synthase - insect - elicitors - volatiles - oviposition
Plants can recruit parasitic wasps in response to egg deposition by herbivorous insects¿a sophisticated indirect plant defense mechanism. Oviposition by the Large Cabbage White butterfly Pieris brassicae on Brussels sprout plants induces phytochemical changes that arrest the egg parasitoid Trichogramma brassicae. Here, we report the identification of an elicitor of such an ovipositioninduced plant response. Eliciting activity was present in accessory gland secretions released by mated female butterflies during egg deposition. In contrast, gland secretions from virgin female butterflies were inactive. In the male ejaculate, P. brassicae females receive the anti-aphrodisiac benzyl cyanide (BC) that reduces the females¿ attractiveness for subsequent mating. We detected this pheromone in the accessory gland secretion released by mated female butterflies. When applied onto leaves, BC alone induced phytochemical changes that arrested females of the egg parasitoid. Microarray analyses revealed a similarity in induced plant responses that may explain the arrest of T. brassicae to egg-laden and BC-treated plants. Thus, a male-derived compound endangers the offspring of the butterfly by inducing plant defense. Recently, BC was shown to play a role in foraging behavior of T. brassicae, by acting as a cue to facilitate phoretic transport by mated female butterflies to oviposition sites. Our results suggest that the antiaphrodisiac pheromone incurs fitness costs for the butterfly by both mediating phoretic behavior and inducing plant defense.
Prey and non-prey Arthropods sharing a host plant: Effects on induced volatile emission and predator attraction
Boer, J.G. de; Hordijk, C.A. ; Posthumus, M.A. ; Dicke, M. - \ 2008
Journal of Chemical Ecology 34 (2008). - ISSN 0098-0331 - p. 281 - 290.
herbivore-induced volatiles - spodoptera-exigua - fungal-infection - natural enemies - jasmonic acid - tetranychus-urticae - parasitic wasps - cabbage plants - damaged plants - salicylic-acid
It is well established that plants infested with a single herbivore species can attract specific natural enemies through the emission of herbivore-induced volatiles. However, it is less clear what happens when plants are simultaneously attacked by more than one species. We analyzed volatile emissions of lima bean and cucumber plants upon multi-species herbivory by spider mites (Tetranychus urticae) and caterpillars (Spodoptera exigua) in comparison to single-species herbivory. Upon herbivory by single or multiple species, lima bean and cucumber plants emitted volatile blends that comprised mostly the same compounds. To detect additive, synergistic, or antagonistic effects, we compared the multi-species herbivory volatile blend with the sum of the volatile blends induced by each of the herbivore species feeding alone. In lima bean, the majority of compounds were more strongly induced by multi-species herbivory than expected based on the sum of volatile emissions by each of the herbivores separately, potentially caused by synergistic effects. In contrast, in cucumber, two compounds were suppressed by multi-species herbivory, suggesting the potential for antagonistic effects. We also studied the behavioral responses of the predatory mite Phytoseiulus persimilis, a specialized natural enemy of spider mites. Olfactometer experiments showed that P. persimilis preferred volatiles induced by multi-species herbivory to volatiles induced by S. exigua alone or by prey mites alone. We conclude that both lima bean and cucumber plants effectively attract predatory mites upon multi-species herbivory, but the underlying mechanisms appear different between these species.
Ecogenomic approach to the role of herbivore-induced plant volatiles in community ecology
Snoeren, T.A.L. ; Jong, P.W. de; Dicke, M. - \ 2007
Journal of Ecology 95 (2007)1. - ISSN 0022-0477 - p. 17 - 26.
tritrophic interaction webs - arabidopsis-thaliana - natural enemies - nicotiana-attenuata - defense responses - parasitic wasps - gene-expression - jasmonic acid - (e)-beta-ocimene synthase - terpenoid metabolism
1 Linking new developments in genomics with ecology provides interesting novel tools to address ecological questions in ways that have not been possible up to now. In this paper we address this issue for the ecology of infochemicals and plant¿insect interactions in a food web context. 2 Plants are at the basis of most terrestrial food webs and insects are a dominant animal group interacting with plants. Insect¿plant communities are characterized by direct and indirect interactions, many of which are mediated by infochemicals. Plants respond to insect herbivory with the production of volatiles that attract the enemies of the herbivores, such as insect predators and parasitoids. Moreover, the plant volatiles may be exploited by any organism in the environment and this results in many more infochemically mediated interactions. Thus, a food web is overlaid with an infochemical web. 3 In the past, several manipulative tools have been developed to investigate the role of infochemicals. The rapid advancement of molecular genetics and `-omics¿ technologies results in interesting new tools. A recent development is the use of well-characterized genotypes that are modified in the mechanisms underlying the induced plant volatiles. These genotypes produce precisely manipulated phenotypes that often differ in only a single gene, and can be used to investigate the effect of particular genes on specific interactions. Moreover, these genotypes can be introduced into a natural community to assess the effects of the genetic change and its resulting phenotypic change on interactions with the entire natural community. 4 Furthermore, with the progress in microarray technology it becomes possible to assess the expressed genotype of plants in the field, which can be exploited to investigate expressed genetic variation under field conditions. 5 These developments are expected to be only the beginning of a successful integration of -omics technologies, such as transcriptomics and metabolomics, with community ecology into the new research field of ecogenomics. 6 In this review we present the current status and discuss the prospects for the future of an ecogenomic approach to the role of herbivore-induced plant volatiles in insect¿plant community ecology.
Infochemicals structure marine, terrestrial and freshwater food webs: Implications for ecological informatics
Vos, M. ; Vet, L.E.M. ; Wackers, F.L. ; Middelburg, J.J. ; Putten, W.H. van der; Mooij, W.M. ; Heip, C.H.R. ; Donk, E. van - \ 2006
Ecological Informatics 1 (2006)1. - ISSN 1574-9541 - p. 23 - 32.
antarctic procellariiform seabirds - dimethyl sulfide - inducible defenses - population-dynamics - tritrophic system - foraging success - cotesia-rubecula - parasitic wasps - plant volatiles - natural enemies
Here we consider how information transfer shapes interactions in aquatic and terrestrial food webs. All organisms, whether they are dead or alive, release certain chemicals into their environment. These can be used as infochemicals by any other individual in the food web that has the biological machinery to sense and process such information. Such machinery has evolved in bacteria, plants and animals and has thus become an inextricable part of the mechanisms that underlie feeding relations in food webs. Organisms live in environments suffused with infochemicals and this information network can be tapped into by both predators and their prey. However, it also opens doors to confusion in the face of a bewildering abundance and complexity of information. Infochemical mixing, masking, crypsis and mimicry could cause such confusion, especially in species-rich communities. We provide a point of entry into this field of enquiry by identifying seminal papers and major reviews and by discussing research lines that might enhance our mechanistic understanding of interactions in food webs. We highlight empirical work on the ways in which individuals use infochemicals and discuss model results on how this mediates patterns of population dynamics. We consider implications for ecosystem management and indicate how classical models and novel approaches from ecological informatics may contribute to linking the levels of individuals, populations and communities and their interactions with abiotic structuring forces in ecosystems.
Olfactory responses of banana weevil predators to volatiles from banana pseudostem tissue and synthetic pheromone
Tinzaara, W. ; Gold, C.S. ; Dicke, M. ; Huis, A. van - \ 2005
Journal of Chemical Ecology 31 (2005)7. - ISSN 0098-0331 - p. 1537 - 1553.
induced plant volatiles - infested pear trees - sordidus germar col - cosmopolites-sordidus - aggregation pheromone - parasitic wasps - pest-management - bark beetles - chemical communication - carnivorous arthropods
As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and Pheidole megacephala (Hymenoptera: Formicidae), are normally found in association with weevil-infested rotten pseudostems and harvested stumps. We investigated whether these predators are attracted to such environments in response to volatiles produced by the host plant, by the weevil, or by the weevil¿plant complex. We evaluated predator responses towards volatiles from banana pseudostem tissue (synomones) and the synthetic banana weevil aggregation pheromone Cosmolure+ in a two-choice olfactometer. The beetle D. abdominale was attracted to fermenting banana pseudostem tissue and Cosmolure+, whereas the ant P. megacephala was attracted only to fermented pseudostem tissue. Both predators were attracted to banana pseudostem tissue that had been damaged by weevil larvae irrespective of weevil presence. Adding pheromone did not enhance predator response to volatiles from pseudostem tissue fed on by weevils. The numbers of both predators recovered with pseudostem traps in the field from banana mats with a pheromone trap were similar to those in pseudostem traps at different distance ranges from the pheromone. Our study shows that the generalist predators D. abdominale and P. megacephala use volatiles from fermented banana pseudostem tissue as the major chemical cue when searching for prey
Combined transcript and metabolite analysis reveals genes involved in spider mite induced volatile formation in cucumber plants
Mercke, P. ; Kappers, I.F. ; Verstappen, F.W.A. ; Vorst, O.F.J. ; Dicke, M. ; Bouwmeester, H.J. - \ 2004
Plant Physiology 135 (2004)4. - ISSN 0032-0889 - p. 2012 - 2024.
herbivore-induced volatiles - jasmonic-acid - acyclic homoterpenes - indirect defense - parasitic wasps - artemisia-annua - bean-leaves - cdna-clone - zea-mays - biosynthesis
Many plants have an indirect defense against herbivores by emitting volatiles that attract carnivorous enemies of the herbivores. In cucumber (Cucumis sativus) the production of carnivore attractants can be induced by herbivory or jasmonic acid spraying. From the leaves of cucumber plants with and without spider mite infestation, two subtractive cDNA libraries were made that were enriched in cDNA fragments up- or down-regulated by spider mite infestation. A total of 713 randomly selected clones from these libraries were used to make a cDNA microarray. Subsequently, cucumber plants were sprayed with jasmonic acid, mechanically damaged, infested with spider mites, or left untreated (control). Leaf samples were taken at a range of different time points, and induced volatile compounds and mRNA (from the same leaves) were collected. cDNAs prepared from the mRNA were hybridized to the clones on the microarray. The resulting gene expression profiles were analyzed in combination with volatile production data in order to gain insight in the possible involvement of the studied genes in the synthesis of those volatiles. The clones on the microarray and the induced cucumber volatiles could be grouped into a number of clusters in which specific biosynthetic genes clustered with the product of that pathway. For example, lipoxygenase cDNA clones clustered with the volatile (Z)-3-hexenyl acetate and the volatile sesquiterpene (E,E)- -farnesene clustered with an up-regulated sesquiterpene synthase fragment. This fragment was used to screen a cDNA library which resulted in the cloning of the cucumber (E,E)--farnesene and (E)--caryophyllene synthases. The use of combined global gene expression analysis and metabolite analysis for the discovery of genes involved in specific biosynthetic processes is discussed.
Experience with methyl salicylate affects behavioural responses of a predatory mite to blends of herbivore-induced plant volatiles
Boer, J.G. de; Dicke, M. - \ 2004
Entomologia Experimentalis et Applicata 110 (2004)2. - ISSN 0013-8703 - p. 181 - 189.
anthocorid predators - parasitic wasps - abiotic factors - corn plants - emissions - prey - attraction - involvement - variability - hymenoptera
Many natural enemies of herbivorous arthropods use herbivore-induced plant volatiles to locate their prey. These foraging cues consist of mixtures of compounds that show a considerable variation within and among plantherbivore combinations, a situation that favours a flexible approach in the foraging behaviour of the natural enemies. In this paper, we address the flexibility in behavioural responses of the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) to herbivore-induced plant volatiles. In particular, we investigated the effect of experience with one component of a herbivore-induced volatile blend: methyl salicylate (MeSA). We compared the responses of three groups of predatory mites: (1) those reared from egg to adult on Tetranychus urticae Koch (Acari: Tetranychidae) on lima bean plants (Phaseolus lunatus L. that produces MeSA), (2) those reared on T. urticae on cucumber (Cucumus sativus L. that does not produce MeSA), and (3) those reared on T. urticae on cucumber in the presence of synthetic MeSA. Exposure to MeSA during the rearing period (groups 1 and 3) resulted in an attraction to the single compound MeSA in a Y-tube olfactometer. Moreover, exposure to MeSA affected the choice of predatory mites between two volatile blends that were similar, except for the presence of MeSA. Predators reared on lima bean plants preferred the volatile blend from T. urticae-induced lima bean (including MeSA) to the volatile blend from jasmonic-acid induced lima bean (lacking MeSA), but predators reared on cucumber preferred the volatile blend from the latter. Predatory mites reared on cucumber in the presence of synthetic MeSA did not discriminate between these two blends. Exposure to MeSA for 3 days in the adult phase, after rearing on cucumber, also resulted in attraction to the single compound MeSA. We conclude that a minor difference in the composition of the volatile blend to which a predatory mite is exposed can explain its preferences between two odour sources.
Induction of direct and indirect plant responses by jasmonic acid, low spider mite densities, or a combination of jasmonic acid treatment and spider mite infestation
Gols, G.J.Z. ; Roosjen, M. ; Dijkman, H. ; Dicke, M. - \ 2003
Journal of Chemical Ecology 29 (2003)12. - ISSN 0098-0331 - p. 2651 - 2666.
herbivore-induced plant - tetranychus-urticae - phytoseiulus-persimilis - nicotiana-attenuata - biological-control - induced volatiles - beta-glucosidase - parasitic wasps - predatory mites - manduca-sexta
Jasmonic acid (JA) and the octadecanoid pathway are involved in both induced direct and induced indirect plant responses. In this study, the herbivorous mite, Tetranychus urticae, and its predator, Phytoseiulus persimilis, were given a choice between Lima bean plants induced by JA or spider mites and uninduced control plants. Infestation densities resulting in the induction of predator attractants were much lower than thus far assumed, i.e., predatory mites were significantly attracted to plants that were infested for 2 days with only one or four spider mites per plant. Phytoseiulus persimilis showed a density-dependent response to volatiles from plants that were infested with different numbers of spider mites. Similarly, treating plants with increasing concentrations of JA also led to increased attraction of P. persimilis. Moreover, the duration of spider mite infestation was positively correlated with the proportion of predators that were attracted to mite-infested plants. A pretreatment of the plants with JA followed by a spider mite infestation enhanced the attraction of P. persimilis to plant volatiles compared to attraction to volatiles from plants that were only infested with spider mites and did not receive a pretreatment with JA. The herbivore, T. urticae preferred leaf tissue that previously had been infested with conspecifics to uninfested leaf tissue. In the case of choice tests with JA-induced and control leaf tissue, spider mites slightly preferred control leaf tissue. When spider mites were given a choice between leaf discs induced by JA and leaf discs damaged by spider mite feeding, they preferred the latter. The presence of herbivore induced chemicals and/or spider mite products enhanced settlement of the mites, whereas treatment with JA seemed to impede settlement.