Oviposition Site Selection Research Articles

The role of contact chemoreception in the host location process of an egg parasitoid

Taste allows insects to detect palatable or toxic foods, identify a mate, and select appropriate oviposition sites. The gustatory system strongly contributes to the survival and reproductive success of many species, yet it is rarely studied in insect parasitoids. In order to locate and assess a host in which they will lay their eggs, female wasps actively search for chemical cues using their sensory organs present mainly on the antennae. In this paper, we studied the role of antennal taste sensilla chaetica in the perception of contact semiochemicals in Trissolcus brochymenae (Hymenoptera: Platygastridae), an egg parasitoid of the brassicaceae pest Murgantia histrionica (Heteroptera: Pentatomidae). Methanolic extracts obtained from male and female hosts elicited action potentials in taste neurons housed in antennal sensilla chaetica, indicating that these sensilla are involved in the perception of non volatile host kairomones. In behavioural assays, wasp females displayed an intense searching behaviour in open arenas treated with host extracts, thus confirming that these kairomones are soluble in polar solvents. We further investigated the extracts by Gas Chromatography-Mass Spectrometry (GC-MS) and found that they contain several compounds which are good candidates for these contact kairomones. This study contributes to better understanding contact chemoreception in egg parasitoids and identifying gustatory receptor neurons involved in the host location process.

Reproductive behaviour of a North African endemic damselfly,Platycnemis subdilatata(Odonata: Platycnemididae) and probable senescence effects

Although the endemic damselfly, Platycnemis subdilatata Selys, 1849, is widespread in the Maghreb, many aspects of its reproductive behaviour, biology and ecology are still unstudied. One particular feature of this species is that its coloration pattern continues to change during maturation and afterwards, which makes it a good model for assessing age effects on behavioural and biological components. This study aims first to investigate the reproductive behaviour and choice of oviposition site, and second to assess clutch size and egg deposition rate as a function of age in a natural population located in North-East Algeria during the reproductive season of 2012. Males seized females next to reproductive sites and in foraging sites. Non-receptive females refused to mate with males by raising their abdomen up while perched or by curving the abdomen up while flying; the angle of abdomen elevation when perched was correlated to male persistence (the number of times that a male tried to grasp the female prothorax while flying over her). Copulation lasted about 14 min, the subsequent oviposition 54 min. Field experiments on oviposition site selection showed that the females prefer to lay eggs in Typha angustifolia leaves. Clutch size and egg deposition rate pattern through age showed an increase in early mature life followed by a decrease later on.

Antennal transcriptome and differential expression of olfactory genes in the yellow peach moth, Conogethes punctiferalis (Lepidoptera: Crambidae).

The yellow peach moth (YPM), Conogethes punctiferalis (Guenée), is a multivoltine insect pest of crops and fruits. Antennal-expressed receptors are important for insects to detect olfactory cues for host finding, mate attraction and oviposition site selection. However, few olfactory related genes were reported in YPM until now. In the present study, we sequenced and characterized the antennal transcriptomes of male and female YPM. In total, 15 putative odorant binding proteins (OBPs), 46 putative odorant receptors (ORs) and 7 putative ionotropic receptors (IRs) were annotated and identified as olfactory-related genes of C. punctiferalis. Further analysis of RT-qPCR revealed that all these olfactory genes are primarily or uniquely expressed in male and female antennae. Among which, 3 OBPs (OBP4, OBP8 and PBP2) and 4 ORs (OR22, OR26, OR44 and OR46) were specially expressed in male antennae, whereas 4 ORs (OR5, OR16, OR25 and OR42) were primarily expressed in female antennae. The predicted protein sequences were compared with homologs in other lepidopteran species and model insects, which showed high sequence homologies between C. punctiferalis and O. furnacalis. Our work allows for further functional studies of pheromone and general odorant detection genes, which might be meaningful targets for pest management.

Volatile cues can drive the oviposition behavior in Odonata

Selection for the oviposition site represents the criterion for the behavioral process of habitat selection for the next generation. It is well known that in Odonata the most general cues are detected visually, but laboratory investigations on the coenagrionid Ischnura elegans showed through behavioral and electrophysiological assays that adults were attracted by olfactory cues emitted by prey and that males of the same species are attracted by female odor.The results of the present behavioral and electrophysiological investigations on I. elegans suggest the involvement of antennal olfactory sensilla in oviposition behavior. In particular, I. elegans females laid in the laboratory significantly more eggs in water from larval rearing aquaria than in distilled or tap water. Moreover, the lack of preference between rearing water and tap water with plankton suggests a role of volatiles related to conspecific and plankton presence in the oviposition site choice. I. elegans may rely on food odor for oviposition site selection, thus supporting the predictions of the “mother knows best” theory. These behavioral data are partially supported by electroantennographic responses. These findings confirm a possible role of olfaction in crucial aspects of Odonata biology.

Foothill Yellow-Legged Frog (Rana boylii) Oviposition Site Choice at Multiple Spatial Scales

Abstract Studies of resource selection at multiple scales are critical to understanding ecological and evolutionary attributes of a species. We analyzed relative abundance, habitat use, and oviposition site selection of Foothill Yellow-Legged Frogs (Rana boylii) at 11 localities across two geographic regions in California (northern Coast Range and Sierra Nevada) over 16 yr. We found narrow ranges for oviposition microhabitat characteristics (water depth, water velocity, and stream substrate) among study localities. At the Main and South forks of the Trinity River, variances of the habitat traits were lower for oviposition microsites than for random points within breeding areas, indicating fine-scale selection. On the South Fork Trinity, egg mass relative abundances were negatively associated with water depth and positively associated with distance from the shoreline, suggesting that breeding areas with high egg mass relative abundances generally occurred in wide shallow areas. We observed long-term repeat...

A Conserved Odorant Receptor Tuned to Floral Volatiles in Three Heliothinae Species.

Odorant receptors (ORs) play an important role in insects to monitor and adapt to the external environment, such as host plant location, oviposition-site selection, mate recognition and natural enemy avoidance. In our study, we identified and characterized OR12 from three closely-related species, Helicoverpa armigera, Helicoverpa assulta, Heliothis virescens, sharing between 90 and 98% of their amino acids. The tissue expression pattern analysis in H. armigera showed that HarmOR12 was strongly expressed both in male and female antennae, but not in other tissues. Functional analysis performed in the heterologous Xenopus expression system showed that all three OR12 were tuned to six structurally related plant volatiles. Electroantennogram recordings from male and female antennae of H. armigera closely matched the data of in vitro functional studies. Our results revealed that OR12 has a conserved role in Heliothinae moths and might represent a suitable target for the control of these crop pests.

Modeling potential river management conflicts between frogs and salmonids

Management of regulated rivers for yellow-legged frogs (Rana boylii) and salmonids exemplifies potential conflicts among species adapted to different parts of the natural flow and temperature regimes. Yellow-legged frogs oviposit in rivers in spring and depend on declining flows and warming temperatures for egg and tadpole survival and growth, whereas salmonid management can include high spring flows and low-temperature reservoir releases. We built a model of how flow and temperature affect frog breeding success. Its mechanisms include adults selecting oviposition sites to balance risks of egg dewatering by decreasing flow versus scouring by high flow, temperature effects on development, habitat selection by tadpoles, and mortality via dewatering and scouring. In simulations of a regulated river managed primarily for salmonids, below-natural temperatures delayed tadpole metamorphosis into froglets, which can reduce overwinter survival. However, mitigating this impact via higher temperatures was predicted to cause adults to oviposit before spring flow releases for salmonids, which then scoured the egg masses. The relative timing of frog oviposition and high flow releases appears critical in determining conflicts between salmonid and frog management.

Keeping the golden mean: plant stiffness and anatomy as proximal factors driving endophytic oviposition site selection in a dragonfly

Oviposition site selection is a crucial component of habitat selection in dragonflies. The presence of appropriate oviposition plants at breeding waters is considered to be one of the key habitat determinants for species laying eggs endophytically. Thus, Lestes macrostigma, a species which is regarded as threatened in Europe because of its highly disjunct distribution, typically prefers to lay eggs in the sea club rush Bolboschoenus maritimus. However, little is known about how the anatomical and mechanical properties of plant tissues determine the choice of L. macrostigma females. We examined green shoots of six plant species used by L. macrostigma for oviposition, either in the field (actual oviposition plants) or under experimental conditions (potential oviposition plants), to analyse anatomical and mechanical properties of shoots in a framework of known preferences regarding plant substrates for oviposition. As expected, the anatomy of shoots differed between representatives of two plant families, Cyperaceae and Juncaceae, most essentially in the distribution of supporting bundles and the presence of large aeriferous cavities that may affect egg placing within a shoot. The force necessary to puncture the tested plant samples ranged from 360 to 3298 mN, and their local stiffness ranged from 777 to 3363N/m. We show that the shoots of B. maritimus, the plant most preferred by L. macrostigma, have intermediate characteristics regarding both the stiffness and specific anatomical characteristics. The bending stiffness of the ovipositor in L. macrostigma was estimated as 1414N/m, one of the highest values recorded for zygopteran dragonflies so far. The ecological and behavioural implications of plant choice mechanisms in L. macrostigma are discussed in the context of the disjunct distribution of this species.

Oviposition site selection by Japanese gypsy moth (Lymatria dispar japonica) in a warm-temperate secondary forest in western Japan

The larvae of Japanese gypsy moth (JGM, Lymantria dispar japonica) are highly polyphagous and considered a serious pest that cause significant ecological and economic losses in forests. Monitoring of egg masses is important to prevent large outbreaks of JGM from occurring in their native range. To investigate oviposition site selection by JGM, we analyzed the occurrence and spatial distribution of egg masses across various evergreen tree species within a secondary forest dominated by evergreen broad-leaved trees in western Japan, following a large outbreak. Egg masses were concentrated on the abaxial surfaces of the leaves of a few evergreen tree species. There was a strong preference for Camellia japonica L., on which more than 75% of the egg masses were found. Egg masses were only found on evergreen tree species with large leaves (leaf area >10 cm2 and leaf dry mass >0.1 g). The spatial distribution of egg masses were clustered at scales around 1‒2 m. For effective monitoring of JGM egg masses in warm-temperate evergreen broad-leaved forests of Japan, the abaxial surfaces of the most abundant evergreen broadleaved trees with large leaves should be checked. If egg masses are found, it is likely that nearby trees of the same species will also have egg masses. Large trees should be checked thoroughly for occurrence of multiple egg masses.

Settling down to dine on a dioecious Gondwanan relict: why are Aacanthocnema dobsoni nymphs more abundant at the base of branchlets?

AbstractFemale herbivorous insects often dictate the distributions of offspring through oviposition site selection. The optimal oviposition hypothesis proposes that sites selected should benefit offspring because they provide the best diets, but distributions can reflect adult responses to non‐dietary factors. On its dioecious host [Allocasuarina verticillata (Lam.) L. Johnson (Casuarinaceae)], the largely sessile nymphs of Aacanthocnema dobsoni (Froggatt) (Hemiptera: Triozidae) are most abundant at the bases of the equisetoid, photosynthetic branchlets and can also be associated with chlorosis. We asked whether the distribution of nymphs could be explained by the nutritional quality of hosts (at tree and branchlet levels) and investigated the nutritional implications of chlorosis. Binary choice oviposition bioassays revealed that female psyllids exhibited a weak preference for the apical (younger) halves of branchlets of male and female trees over basal (older) halves. In the absence of nymphs, basal and apical halves of branchlets of both sexes had comparable concentrations of amino N. The severity of chlorosis of individual female branchlets was positively related to the density of nymphs. Along entire female branchlets, chlorosis was associated with significant reductions in the concentrations of certain amino acids (including glutamic acid). For basal halves of female branchlets, chlorosis was associated with increased concentrations of a different suite of amino acids, i.e., evidence of nutritional enhancement. Fifth instars from female branchlets were slightly larger than those from male branchlets but nymphal morphology is constrained by branchlet diameter. The conformation of the host (especially the spaces between the scale‐like leaves) appears to dictate oviposition site selection more than nutritional quality. Nutritional enhancement is suggested to explain the absence of a strong linkage between preference and performance. Aggregation of adults (and eggs) at the base of branchlets could arise from heightened risk of dislodgement by wind at the ends of branchlets and enhanced mate finding in less exposed locations.

Oviposition preference of aphidophagous hoverflies toward oviposition site quality: The presence of intra- and interspecific competitor, glucosinolate content, and prey species

The selection of oviposition sites by aphidophagous insects is complex because of tritrophic interactions among host plant, aphid, and natural enemies. Several factors are known to affect the choice of oviposition site by aphidophagous hoverflies. The decisions of ovipositing females about where to lay their eggs are even more important in insects whose newly hatched offspring have limited dispersal ability, such as most aphidophages. In this study, we focused on the oviposition responses of two generalist aphidophagous syrphids (Eupeodes luniger and Episyrphus balteatus) toward host plant–aphid combinations differing in sinigrin content and the presence of intra- and interspecific competitors. The oviposition preference of Eupeodes luniger was significantly influenced in a reverse manner by the presence of intraguild competitors and also by the sinigrin content of host plants (P<0.0001 for both factors). Likewise, the overall proportion of eggs laid by female Episyrphus balteatus was greater on aphids with relatively low levels of sinigrin. Our findings help in understanding the factors governing the oviposition responses of aphidophagous predators.

Myrmecophilous butterflies utilise ant–treehopper associations as visual cues for oviposition

1. Selection of a safe oviposition site is important for herbivorous insects whose immature stages have limited mobility. Female herbivores rely on environmental cues for this choice, and presence of natural enemies or mutualistic partners may be important in this process.2. Some butterflies have mutualistic interactions with ants (myrmecophily), in which caterpillars offer a nutritional liquid and gain protection against natural enemies. Participants in butterfly–ant mutualisms may utilise signals to initiate interactions, but the use of visual cues by ovipositing myrmecophilous butterflies remains uncertain.3. Larvae of facultatively myrmecophilous Parrhasius polibetes (Lycaenidae) feed on Schefflera vinosa, and females prefer to oviposit near aggregations of the ant‐tended treehopper Guayaquila xiphias, where caterpillars survive better due to increased ant attendance. Given the conspicuousness of ant–treehopper associations, it was investigated whether butterflies use them as visual cues for oviposition and, if so, which participants of the association are used as cues: ants, treehoppers, or both.4. Experiments using dried insects on paired branches revealed that females visually recognise ants and ant–treehopper associations, using them for egg‐laying decisions. However, presence of a treehopper aggregation alone had no effect on oviposition choices.5. This is a first insight into the importance of visual discrimination for ovipositing myrmecophilous butterflies. The results show that facultative mutualisms can be important enough to promote a behavioural adaptation (visual detection of ants) reinforcing the interaction. Our research highlights the importance of the behavioural interface within complex multispecies systems.

Emergent Vegetation Coverage and Human Activities Influence Oviposition Microhabitat Selection by Invasive Bullfrogs (Lithobates catesbeianus) in Southwestern China

Abstract Oviposition site selection is critical to increase offspring fitness for aquatic-breeding anurans, which generally lack posthatching parental care. Understanding factors that influence oviposition microhabitat choice would be helpful for managing and controlling invasive amphibians, such as the American Bullfrog (Lithobates catesbeianus), implicated in the decline of anuran populations across its invasive range. Factors that influence bullfrog oviposition microhabitat selection, however, remain mostly unknown. On the basis of field surveys from 2008 to 2013, we investigated 46 oviposition sites used by bullfrogs and 46 adjacent random unused sites and evaluated eight characteristics that could potentially influence oviposition site selection by bullfrogs in Caohai wetland, southwestern China, a global biodiversity conservation hot spot. We used model averaging of generalized linear mixed-effects models, using Akaike information criterion, hierarchical partitioning, and an ordination principal com...

Suboptimal Larval Habitats Modulate Oviposition of the Malaria Vector Mosquito Anopheles coluzzii.

Selection of oviposition sites by gravid females is a critical behavioral step in the reproductive cycle of Anopheles coluzzii, which is one of the principal Afrotropical malaria vector mosquitoes. Several studies suggest this decision is mediated by semiochemicals associated with potential oviposition sites. To better understand the chemosensory basis of this behavior and identify compounds that can modulate oviposition, we examined the generally held hypothesis that suboptimal larval habitats give rise to semiochemicals that negatively influence the oviposition preference of gravid females. Dual-choice bioassays indicated that oviposition sites conditioned in this manner do indeed foster significant and concentration dependent aversive effects on the oviposition site selection of gravid females. Headspace analyses derived from aversive habitats consistently noted the presence of dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS) and 6-methyl-5-hepten-2-one (sulcatone) each of which unitarily affected An. coluzzii oviposition preference. Electrophysiological assays across the antennae, maxillary palp, and labellum of gravid An. coluzzii revealed differential responses to these semiochemicals. Taken together, these findings validate the hypothesis in question and suggest that suboptimal environments for An. coluzzii larval development results in the release of DMDS, DMTS and sulcatone that impact the response valence of gravid females.

Does insect mother know under what conditions it will make their offspring live?

According to the optimal oviposition theory, the larval success of insects depends on the oviposition site selection by females. Females are expected to choose a site with many resources and few competitors or predators to allow the best performance for their progeny, assuming that "mother knows best." However, this is not systematically observed. The Aphidoletes aphidimyza larvae are generalist aphid predators and females consequently lay their eggs near or inside aphid colonies. The goal of this study was to investigate the impact of intraspecific competition on oviposition behavior of A. aphidimyza females. First, we counted the number of eggs laid by a female on a leaf with 20 aphids, in the presence of 0, 2, 4, or 6 conspecific eggs or in the absence of eggs but in presence of 3 virgin females. The same experiment was also performed under choice condition with 2 oviposition sites. Our results show that the presence of low densities of conspecific eggs, or the presence of conspecific females, have no significant impact on the number of eggs laid by A. aphidimyza females. One of the hypotheses advanced to explain these results is the advantages of conspecifics presence. At low densities, the presence of eggs on an oviposition site can indicate the suitability of the site for the females. The conspecific presence can also insure a dilution effect against predator and increase the presence of potential mating partners for this monogenic species.

Aedes albopictus (Diptera: Culicidae) Oviposition Preference as Influenced by Container Size and Buddleja davidii Plants.

Aedes albopictus (Skuse) is a container-breeding mosquito commonly found in residential areas of its range in the United States. Mosquitoes are known to utilize flowering plants for sugar acquisition. Limited information is known about the influences on oviposition site selection, outside of container size. Residential areas are often landscaped with a variety of flowering plants and are known to provide numerous sizes of potential larval developmental sites for container-breeding mosqutioes. Through screened enclosure and field studies, the oviposition preference of Ae. albopictus for containers of three selected sizes (473, 946 and 1,892 ml) and the influence of flowering butterfly bush (Buddleja davidii Franchett cultivar 'Guinevere') plants were examined. Our results document that significantly more eggs were oviposited in the largest containers. Additionally, significantly more eggs were oviposited in containers adjacent to flowering butterfly bushes than in those without a flowering butterfly bush. Finally, our results document that flowering butterfly bushes exerted greater influence over Ae. albopictus oviposition decisions than did container size. Our findings can be applied to several aspects of Ae. albopictus surveillance and control.

Behaviour and dispersal in adult Taeniopteryx nebulosa (Linnaeus, 1758) and Perlodes microcephalus (Pictet, 1833) (Plecoptera) in Denmark

ABSTRACTAdult Taeniopteryx nebulosa (Linnaeus, 1758) and Perlodes microcephalus (Pictet, 1833) emerge late winter to early spring in Danish streams. Based on 13 years of study, we have provided new data and discussed little-known aspects of biology of these two species. Taeniopteryx nebulosa male deposits a spermatophore on the female gonopore. Both species are poor fliers and seek high posts for take-off, where they thermoregulate by basking in a pre-flight sun posture for heating flight muscles. Oviposition flight is erratic and short. The females skim back to land. Taeniopteryx nebulosa eggs drift a long distance as single eggs before adhering to vegetation. Perlodes microcephalus eggs drift a short distance as intact eggpackets before they fasten and disintegrate on the bottom. Perlodes microcephalus females select oviposition sites on or close to upstream a riffle. This is critical in ensuring that eggs fasten on stable gravel and stone bottoms. The fast recolonisation of P. microcephalus in Danish streams following restoration measures indicates efficient dispersal ability despite poor flight performance. Adults of both species adhere to clothes, feather and fur. Taeniopteryx nebulosa tarsomeres have many hooked setae, P. microcephalus tarsomeres have some hooked setae and a dense cover of microtrichia. They may disperse by hitchhiking on birds and mammals.

An integrated hybrid microfluidic device for oviposition-based chemical screening of adult Drosophila melanogaster.

Chemical screening using Drosophila melanogaster (the fruit fly) is vital in drug discovery, agricultural, and toxicological applications. Oviposition (egg laying) on chemically-doped agar plates is an important read-out metric used to quantitatively assess the biological fitness and behavioral responses of Drosophila. Current oviposition-based chemical screening studies are inaccurate, labor-intensive, time-consuming, and inflexible due to the manual chemical doping of agar. In this paper, we have developed a novel hybrid agar-polydimethylsiloxane (PDMS) microfluidic device for single- and multi-concentration chemical dosing and on-chip oviposition screening of free-flying adult stage Drosophila. To achieve this, we have devised a novel technique to integrate agar with PDMS channels using ice as a sacrificial layer. Subsequently, we have conducted single-chemical toxicity and multiple choice chemical preference assays on adult Drosophila melanogaster using zinc and acetic acid at various concentrations. Our device has enabled us to 1) demonstrate that Drosophila is capable of sensing the concentration of different chemicals on a PDMS-agar microfluidic device, which plays significant roles in determining oviposition site selection and 2) investigate whether oviposition preference differs between single- and multi-concentration chemical environments. This device may be used to study fundamental and applied biological questions in Drosophila and other egg laying insects. It can also be extended in design to develop sophisticated and dynamic chemical dosing and high-throughput screening platforms in the future that are not easily achievable with the existing oviposition screening techniques.

Identification of Putative Olfactory Genes from the Oriental Fruit Moth Grapholita molesta via an Antennal Transcriptome Analysis.

BackgroundThe oriental fruit moth, Grapholita molesta, is an extremely important oligophagous pest species of stone and pome fruits throughout the world. As a host-switching species, adult moths, especially females, depend on olfactory cues to a large extent in locating host plants, finding mates, and selecting oviposition sites. The identification of olfactory genes can facilitate investigation on mechanisms for chemical communications.Methodology/Principal FindingWe generated transcriptome of female antennae of G.molesta using the next-generation sequencing technique, and assembled transcripts from RNA-seq reads using Trinity, SOAPdenovo-trans and Abyss-trans assemblers. We identified 124 putative olfactory genes. Among the identified olfactory genes, 118 were novel to this species, including 28 transcripts encoding for odorant binding proteins, 17 chemosensory proteins, 48 odorant receptors, four gustatory receptors, 24 ionotropic receptors, two sensory neuron membrane proteins, and one odor degrading enzyme. The identified genes were further confirmed through semi-quantitative reverse transcription PCR for transcripts coding for 26 OBPs and 17 CSPs. OBP transcripts showed an obvious antenna bias, whereas CSP transcripts were detected in different tissues.ConclusionAntennal transcriptome data derived from the oriental fruit moth constituted an abundant molecular resource for the identification of genes potentially involved in the olfaction process of the species. This study provides a foundation for future research on the molecules involved in olfactory recognition of this insect pest, and in particular, the feasibility of using semiochemicals to control this pest.

Identification of Host-Plant Volatiles and Characterization of Two Novel General Odorant-Binding Proteins from the Legume Pod Borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae).

Chemoreception is a key feature in selection of host plant by phytophagous insects, and odorant-binding proteins (OBPs) are involved in chemical communication of both insects and vertebrates. The legume pod borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) is one of the key pest species of cowpea and widely distributed throughout tropical and subtropical regions, causing up to 80% of yield loss. In this study, we investigated the electrophysiological responses of female M. vitrata to floral volatiles from V. unguiculata. Seventeen electroantennogram-active compounds were identified from floral volatiles of V. unguiculata by coupled gas chromatography-electroantennography (GC-EAD) and gas chromatography-mass spectrometry (GC-MS). Then, we cloned two novel full-length GOBP genes (MvitGOBP1 and MvitGOBP2) from the antennae of M. vitrata using reverse transcription PCR. Protein sequence analysis indicated that they shared high sequence similarity with other Pyralididae insect GOBPs and had the typical six-cysteine signature. Real-time PCR analysis indicated that MvitGOBP1-2 mRNA was highly expressed in the antennae of female adult with several thousands-fold difference compare to other tissue. Next, the recombinant MvitGOBP1-2 was expressed in Escherichia coli and purified using Ni ion affinity chromatography. Fluorescence binding assays demonstrated that MvitGOBP1-2 had different binding affinities with 17 volatile odorant molecules including butanoic acid butyl ester, limonene, 4-ethylpropiophenone, 1H-indol-4-ol, butanoic acid octyl ester and 2-methyl-3-phenylpropanal. In the field trapping experiment, these six floral volatiles could effectively attract female moths and showed significant difference compared with the blank lure. These results suggested that MvitGOBPs and the seventeen floral volatiles are likely to function in the olfactory behavior response of female moths, which may have played crucial roles in the selection of oviposition sites. The six compounds that we have identified from the volatiles of V. unguiculata may provide useful information for exploring efficiency monitoring and integrated pest management strategies of this legume pod borer in the field.