Chemical Lures Research Articles

Frequency and behavior of Melipona stingless bees and orchid bees (Hymenoptera: Apidae) in relation to floral characteristics of vanilla in the Yucatán region of Mexico.

Vanilla planifolia is native to the Mexican tropics. Despite its worldwide economic importance as a source of vanilla for flavoring and other uses, almost all vanilla is produced by expensive hand-pollination, and minimal documentation exists for its natural pollination and floral visitors. There is a claim that vanilla is pollinated by Melipona stingless bees, but vanilla is more likely pollinated by orchid bees. Natural pollination has not been tested in the Yucatán region of Mexico, where both vanilla and potential native bee pollinators are endemic. We document for the first time the flowering process, nectar production and natural pollination of V. planiflora, using bagged flower experiments in a commercial planting. We also assessed the frequency and visitation rates of stingless bees and orchid bees on flowers. Our results showed low natural pollination rates of V. planifolia (~ 5%). Only small stingless bees (Trigona fulviventris and Nannotrigona perilampoides) were seen on flowers, but no legitimate visits were witnessed. We verified that there were abundant Euglossa and fewer Eulaema male orchid bees around the vanilla plants, but neither visited the flowers. The introduction of a colony of the stingless bee Melipona beecheii and the application of chemical lures to attract orchid bees failed to induce floral visitations. Melipona beecheii, and male orchid bees of Euglossa viridissima and E. dilemma may not be natural pollinators of vanilla, due to lack of attraction to flowers. It seems that the lack of nectar in V. planifolia flowers reduces the spectrum of potential pollinators. In addition, there may be a mismatch between the attractiveness of vanilla floral fragrances to the species of orchid bees registered in the studied area. Chemical studies with controlled experiments in different regions would be important to further elucidate the potential pollinators of vanilla in southern Mexico.

Evaluation of behavioral response of Blitopertha lineolata (Fischer von Waldheim, 1824) (Coleoptera: Rutelidae) to visual and chemical cues

During field trapping of Tropinota hirta (Cetoniidae) by blue traps baited with the respective floral lure regular catches Blitopertha lineolata were recorded in an experimental field in Sofia plain, Bulgaria. In order to investigate the relative importance of chemical and visual cues on the attraction response of this species, several field tests were performed using CSALOMON® VARb3k funnel traps in Sofia during 2007-2009. In 2007, we evaluated the behavioral response of the adults to four variants of traps - transparent and blue unbaited traps, and transparent and blue traps baited with the lure for T. hirta. The most numerous catches of B. lineolata were recorded in blue traps independently of the presence or absence of the floral bait. In a subsequent test we compared the attractiveness of baited traps developed for cetoiid beetle species: T. hirta, Oxythyrea funesta, Cetonia aurata and Protaetia cuprea (Cetoniidae). The most numerous catches were recorded in traps for C. aurata/P. cuprea but there was no significant difference between mean catches in these traps and traps for T. hirta. The color preference of B. lineolata was evaluated comparing the colors, white, blue, yellow, fluorescent yellow or transparent of VARb3 traps without chemical lures. Results of these tests revealed that highest mean numbers of adults were recorded in the blue traps followed by the fluorescent yellow traps in 2008, and white and yellow traps in 2009. During this study, the seasonal flight of B. lineolata in the Sofia region started at the second half of May and lasted till the beginning of July in 2007, 2008 and 2009. Blue CSALOMON® VARb3k funnel traps can be considered as an efficient tool for detection and monitoring the seasonal flight of this species. Further research is needed to find a semiochemical attractant to B. lineolata. New distributional data for this species in Bulgaria are provided as well.

Field evaluation of electrophysiologically-active dung volatiles as chemical lures for trapping of dung beetles

Dung beetles are economically important beneficial insects that process dung. To locate this source, they use volatile organic compounds (VOCs). The objectives of the study were to evaluate the attractiveness of ten electrophysiologically-active dung volatiles (phenol, skatole, indole, p-cresol, butanone, butyric acid, eucalyptol, dimethyl sulphide, dimethyl disulphide, and toluene) to dung beetles in the field and to investigate how the composition of volatile blends influences efficacy as lures for use in traps. Six combinations of the compounds were compared with field collected cattle dung bait and a negative control, across three seasons. Both dung and synthetic baits captured all exotic dung beetle species present in the study area. A six-compound mix (M1), comprising major dung volatiles, served as an attractive chemical mixture. The addition of dimethyl sulphide, dimethyl disulphide (M2) and toluene (M4) enhanced attractancy of M1 for dung beetles, while eucalyptol (M3) decreased the attractancy. The degree of attraction by various dung beetle species to synthetic baits varied, but baits proved to be effective, especially for summer trapping. The trap design used in this study presented a convenient and practical way to sample dung beetle and other associated scarabs from open pastures. The attraction of introduced dung beetle species to synthetic baits is documented here for the first time in Australia. In addition, necrophagous Omorgus sp. is reported here for the first time to be attracted to synthetic baits. They showed a significant attraction to the mixture containing dimethyl sulphide and dimethyl disulphide (M2). The current study represents a promising first step towards formulating a synthetic chemical lure for dung beetles, offering a consistent, standardised, and bio-secure trapping method compared to use of naturally occurring dung baits, especially as a multi-species lure.

Semiochemicals from Trichosanthes anguina (Cucurbitaceae) plants influence behavior in Diaphania indica.

First to third instars of Diaphania indica (Saunders) (Lepidoptera: Crambidae) feed on the lower surface of leaves, while fourth and fifth instars gregariously consume leaves of Trichosanthes anguina L. After defoliating, the caterpillar also attacks flowers and fruits of the plant and finally, results in loss of crop yield. Therefore, behavioral responses of D. indica adults were investigated to volatiles from undamaged (UD), insect-damaged (ID, plants after feeding by D. indica larvae) and jasmonic acid (JA) treated T. anguina plants. Females showed attraction to volatiles of UD and ID plants of three T. anguina cultivars [MNSR-1 (MNS), Baruipur Long (BAR) and Polo No. 1 (POLO)] in Y-tube olfactometer bioassays. Females did not show significant negative responses from volatiles of JA treated plants. Females were more attracted to volatiles of ID plants than UD plants. Females showed attraction to volatiles of UD or ID plants compared to JA treated plants. Females were attracted to certain synthetic blends resembling volatiles of insect-damaged MNS, BAR and POLO plants in olfactometer bioassays. Females could not distinguish among these three certain synthetic blends in olfactometer bioassays. A synthetic blend of 3Z-hexen-1-ol, α-pinene, hexyl acetate, benzyl alcohol and 6Z-nonenal at mole ratios of 1.47:1.20:1:1.82:1.21 was prepared at 20 mg/mL dichloromethane and 100 μL when used as lure in funnel traps resulted in the capture of the highest number of D. indica adults in field trails. The earlier five-component chemical lure could be used in traps in an integrated pest management program of the insect pest, D. indica. © 2023 Society of Chemical Industry.

Nontarget catches of traps with chemical lures may refer to the flower‐visitation, probable pollination, and feeding of bush crickets (Ensifera: Tettigoniidae)

AbstractThe diurnal bees, lepidopterans, and other pollinators are among the most studied flower‐visiting insect taxa. They mostly play distinct functions in temperate grasslands and ecotones of grassland‐forest mosaics (such as in forest steppes). Although orthopterans are widely distributed in these habitats, however, their flower visitation is nearly unknown, especially in the temperate zone. During the development of traps with chemical lures to catch Lepidoptera pests, large numbers of Orthoptera were caught that provide a chance for studying the flower visitation and odor and indirectly the host plant preference of seven temperate zone Tettigoniidae species. Data on the attractivity of isoamyl alcohol‐based semisynthetic lures for Meconema thalassinum and efficiency of phenylacetaldehyde‐based lures on Leptophyes albovittata and Phaneroptera falcata were reported for the first time. Additionally, analysis of nature photos collected from internet sources, as part of a passive citizen science also supports the revealed preference of these species. Based on photos, the studied orthopterans mainly visit Asteraceae species including the most preferred Tanacetum vulgare, Pulicaria dysenterica, Achillea millefolium, Solidago canadensis, and Centaurea scabiosa. Based on catches of volatile traps, the first data were recorded on the attractivity of phenylacetaldehyde‐ and isoamyl alcohol‐based lures on three temperate zone Orthoptera species. Results of a passive citizen science study strengthen these results that may increase the knowledge on the host plant and habitat preference of Orthoptera species.

Spatial repellency and attractancy responses of some chemical lures against Aedes albopictus (Diptera: Culicidae) and Anopheles minimus (Diptera: Culicidae) using the high-throughput screening system.

We evaluated the behavioral responses of Aedes albopictus and Anopheles minimus to 3 isovaleric acid and lactic acid-based chemical lure blends and 2 individual alcohols, using Spatial Repellency Assay in a high-throughput screening system (HITSS). Five doses of 0.0002, 0.001, 0.0025, 0.005, and 0.01 g were tested per lure. A BG-lure was used as a reference standard. After 10-min exposure, the number of mosquitoes moving toward or away from the treated chamber was calculated. The results showed that all lures were repellent against Ae. albopictus except for Lure-4 (4% w/v isovaleric acid + 2% w/v lactic acid + 0.0025% w/v myristic acid + 2.5% w/v ammonium hydroxide) which showed a nonsignificant attractancy at the lowest dose. Significantly high spatial repellency was observed at the highest dose of all the tested lures including BG-lure. Lure-2 (isoamyl alcohol) was significantly repellent at all the tested doses. Against An. minimus, Lure-5 (0.02% w/v isovaleric acid + 2% w/v lactic acid) showed significant spatial repellency while Lure-4 was significantly attractant, at all the tested doses. All lures, except Lure-4, showed strong spatial repellency at high doses and attractancy or weak spatial repellency at the lowest dose of 0.0002 g. In summary, our study demonstrated that spatial repellency and attractancy of the tested lures were influenced by both the dose tested and the mosquito species. Lure-2 and Lure-4 are potential spatial repellents and attractants, respectively, for malaria and dengue vectors. However, further studies are necessary to confirm these results at a semifield and open field level.

Chikungunya Virus Infection and Gonotrophic Cycle Shape Aedes aegypti Oviposition Behavior and Preferences.

Targeting gravid females through chemical lures is a promising strategy in vector control; however, it requires the understanding of the factors susceptible to alter female oviposition behavior. Here, we evaluated the effect of infection with chikungunya virus (CHIKV) and the number of gonotrophic cycles (GCs) on oviposition activity in A. aegypti. Dual choice oviposition assays were performed, where dodecanoic acid, pentadecanoic acid, n-heneicosane and a Sargasssum fluitans (Børgesen) Børgesen extract were tested in uninfected females and females infected with CHIKV, at the 1st and 2nd GC. Infected females displayed a lower percentage of oviposition and a higher number of eggs laid at the 1st GC. Then, the combined effects of GC and CHIKV were observed on oviposition preferences, with a chemical-dependent effect. For instance, the deterrent effect of n-heneicosane and pentadecanoic acid increased at the 2nd GC in infected females. These results allow for a deeper understanding of the mechanisms involved in oviposition site selection and highlight the need for taking into account physiological stage changes to increase the control programs' efficacy.

A new formulation of screwworm fly attractant with reduced hazardous chemicals and transport restrictions.

New World screwworm flies, Cochliomyia hominivorax (Coquerel), are obligate parasites of warm-blooded animals. They were eradicated from North and Central America during the mid-20th to early-21st centuries using the sterile insect technique (SIT), a method presently employed to maintain a permanent barrier between Central and South America. Lures are an important component of the screwworm eradication program, where they are used for surveillance, sample collection, and strain evaluation in the field. The first chemical lure, later named swormlure, was developed based on the attractiveness of C. hominivorax to volatile organic compounds (VOCs) produced from decomposing animal tissues. The formulation has changed little over the years and presently contains 10 chemicals, one of which is dimethyl disulfide (DMDS). Restrictions on the transport of DMDS have recently impeded its use in swormlure-4 (SL-4). However, dimethyl trisulfide (DMTS) is not as highly restricted and can be shipped via air transportation. Both chemicals are produced by microbial decomposition of animal tissues. Here, we conducted field trials using three releases of sterile C. hominivorax, each comprising approximately 93,000 flies, to test the efficacy of SL-4, containing DMDS, to swormlure-5 (SL-5) containing DMTS. Traps baited with SL-4 and SL-5 captured 575 (mean = 191.7, SD 17.9) and 665 (mean = 221.7, SD 33.2) C. hominivorax, respectively (df = 19, F = 1.294, P = 0.269). However, traps baited with SL-5 captured considerably more Cochliomyia macellaria (Fabricius), a closely related but nontarget fly.

Morphology and location of sensilla in the antennae and ovipositor of Sirex noctilio (Hymenoptera: Siricidae)

The woodwasp Sirex noctilio Fabricius is a major quarantine pest that was reported in China in 2013 and mostly damages Pinus sylvestris var. mongolica. Reverse chemical ecology, which uses chemical lures to catch or block insects from mating is the classic way to control forestry pests. This indicates that insect sensilla play a crucial role in detecting external chemical and physical stimuli. Nonetheless, the categorization and distribution of sensilla on the antennae and ovipositor of S. noctilio are insufficiently specific. In this paper, scanning electron microscopy (SEM) was used to observe the ultrastructure of the sensilla of S. noctilio on the antenna and ovipositor. It was found that the types and distribution of sensilla on the antennae of S. noctilio male and female are consistent, and six types of sensilla are found: sensilla trichodea (ST), sensilla chaetica (SC), Böhm bristles (BB), sensilla basiconica (SB), sensilla ampullacea (SA), and contact chemoreceptors (CC). Besides, there are five types of sensilla on the female ovipositor. In addition to ST, SC and BB, two more types of sensilla are also found: sensilla cavity (SCa) and sensilla coeloconica (SCo). Through identification of the morphology and distribution of the sensilla, the functions of different sensilla in the mating and host selection mechanisms of S. noctilio are proposed, thereby establishing a foundation for S. noctilio chemical communication research.

The longhorn beetles (Coleoptera: Cerambycidae) of Kentucky with notes on larval hosts, adult nectar use, and semiochemical attraction

The longhorn beetle fauna of Kentucky has long been overlooked in the literature with revisions and historic publications reporting few records from the state. Here, we document the occurrence of 222 species of Cerambycidae in Kentucky, with 140 new state records. For each species, we summarize its distribution (overall and in the state), the counties, years, and months in which it has been collected, collecting methods, what collections house the specimens, larval host plants, adult flower visitation, chemical lure attraction, recent taxonomic changes, and other pertinent information about the species. Using this dataset, the bias-corrected Chao1 species richness estimator predicted that 241 species should be found in Kentucky, indicating that our sampling is nearly comprehensive. Additionally, we provide a list of 42 species that have been found in at least one neighboring state and the distance from the closest record of the species to Kentucky; among this candidate list are 11 species known from within 50 km of the state. This checklist remedies the historical oversight of Kentucky cerambycid diversity in the literature, and we hope it will serve as a resource for future collectors, particularly the information on chemical lure attraction, which has not been summarized to this extent for any other state to date.

A chemical lure for trapping both sexes of Amata phegea L.

A chemical lure for trapping both sexes of Amata phegea L.

Nontarget catches of traps with chemical lures may refer to the flower-visitation, probable pollination, and feeding of bush crickets (Ensifera: Tettigoniidae)

Nontarget catches of traps with chemical lures may refer to the flower-visitation, probable pollination, and feeding of bush crickets (Ensifera: Tettigoniidae)

Complex and Beautiful: Unraveling the Intricate Communication Systems Among Plants and Insects.

My research focuses on elucidating the chemical communication systems linking plants, herbivores, and natural enemies. My interests in integrating chemistry and agriculture led to my graduate studies in the emerging field of chemical ecology. My thesis research resulted in the identification, synthesis, and application of boll weevil sex pheromones. My research group subsequently developed chemical lures for more than 20 species of pest insects. I then shifted my focus to some of the first studies of the chemical signals produced by plants being attacked by herbivores. When insects feed, elicitors in the insects' oral secretions, such as volicitin, a fatty acid-amino acid conjugate elicitor, stimulate plants to release volatile organic compounds. Parasitoid wasps learn to associate these species-specific volatiles with their herbivore hosts. These volatiles also prime nearby plants to activate a faster and higher defense response upon attack. Throughout my career, I have collaborated with scientists from diverse disciplines to tackle fundamental questions in chemical ecology and create innovative solutions for insect management. Our collaborative research has fundamentally changed and improved our understanding of the ongoing coevolution of plants, their herbivores, and the natural enemies that attack those herbivores.

Semi-field evaluation of novel chemical lures for Aedes aegypti, Culex quinquefasciatus, and Anopheles minimus (Diptera: Culicidae) in Thailand

BackgroundEntomological surveillance is an important means of assessing the efficacy of insect vector management programs and estimating disease transmission thresholds. Among baited traps, Biogents’ BG-Sentinel (BGS) trap baited with BG-Lure is considered to have the most similar outcome to, and be a possible replacement for, human-landing catches for the epidemiologically relevant monitoring of adult Aedes aegypti and Culex quinquefasciatus. In contrast to the BGS trap, the Black Hole ultraviolet (UV) light trap, which is widely used to catch nocturnal flying insects, is not baited with synthetic human odor-mimicking lures.MethodsWe evaluated the l-lactic acid-based Kasetsart University (KU)-lures nos. 1–6 as novel candidate chemical lures for the diurnal species Ae. aegypti and the nocturnal species Cx. quinquefasciatus using two commercial traps (the BGS trap and the Black Hole UV light trap) in a semi-field screen (SFS) house. Firstly, we optimized the dose of each KU-lure in an SFS house (140 m3). Secondly, six different candidate KU-lures were screened by comparing their percent attraction using a single discriminating dose (0.5 g). Finally, we evaluated the synergism of the KU-lures selected in this way with commercially available traps.ResultsBGS traps baited with KU-lure no. 1 exhibited the greatest percent attraction for Ae. aegypti (29.5% ± 14.3%), whereas those baited with KU-lure no. 6 most strongly attracted Cx. quinquefasciatus (33.3% ± 10.7%). Interestingly, BGS traps treated with 10 g BG-Lure did not significantly attract more Ae. aegypti or Cx. quinquefasciatus than the untreated BGS traps. CO2 at a flow rate of 250 ml/min most strongly attracted both Ae. aegypti and Cx. quinquefasciatus (42.2% ± 14.2% and 75.1% ± 16.9%, respectively). BGS and Black Hole UV light traps with KU-lure no. 6 exhibited a stronger attraction for Cx. quinquefasciatus than untreated traps, and the percent attraction did not differ between the treated traps.ConclusionsSynergistic effects of KU-lures nos. 1 and 6 with the mosquito traps were demonstrated for both the diurnal and nocturnal species in the SFS house assays. However, further studies are urgently needed for the development of species-specific lures to increase trap efficacy in the field for local vector mosquitoes in Thailand.Graphical

A Field Evaluation of the LuciTrap and the Western Australian Trap with Three Different Baits Types for Monitoring Lucilia cuprina and Lucilia sericata in New Zealand

Simple SummaryIn New Zealand, flystrike is caused by two Dipteran species, Lucilia cuprina and Lucilia sericata. This study contrasts four flytrap treatments, the LuciTrap with its combination of three chemical lures (Lucilures) and the Western Australian Trap with three different bait types (LuciLure, Sheep liver with 30% sodium sulphide and squid) during mid-summer. The aim of the study is to assess the most effective trap and bait combination that New Zealand farmers may use on their farms to monitor L. cuprina and L. sericata. This study found that either the LuciTrap or the Western Australian Trap with sheep liver and 30% sodium sulphide were the most effective traps to catch L. cuprina and L. sericata.Flytraps can be used on farms to monitor the populations of primary strike flies (Lucilia cuprina and Lucilia sericata) and, hence, offer a view regarding the incidence of flystrike on sheep. This study aimed to contrast the specificity and effectiveness of the LuciTrap with its combination of three chemical lures (Lucilures) and the Western Australian Trap with three bait types (LuciLure, Sheep liver with 30% sodium sulphide and squid). A mean model and rate model were fitted to the data. The mean model showed no difference (p > 0.05) in the mean weekly catch for L. cuprina between the Western Australian Trap with LuciLures and the Western Australian Trap baited with sheep liver with 30% sodium sulphide (p < 0.05). Whereas, for L. sericata, no difference (p > 0.05) was found between the Western Australian Trap with LuciLures, the Western Australian Trap baited with sheep liver with 30% sodium sulphide and the LuciTrap. The rate model illustrated that the Western Australian Trap with sheep liver with 30% sodium sulphide and LuciTrap did not differ (p > 0.05) for L. cuprina and L. sericata. Combined, these results indicate that New Zealand farmers can use either the LuciTrap or the Western Australian Trap with sheep liver with 30% sodium sulphide to monitor these target species.

Evaluation of Mosquito Attractant Candidates Using a High-Throughput Screening System for Aedes aegypti (L.), Culex quinquefasciatus Say. and Anopheles minimus Theobald (Diptera: Culicidae).

Simple SummaryTrapping mosquitoes can enhance its capture rate by adding attractants such as carbon dioxide or human hosts’ odor-mimicking synthetic blends. Various olfactometers exist to test mosquitos’ behavior, but high-throughput screening system (HITSS)—one of the diffusion assays—has not been applied to developing lures. In this study, six different newly prepared chemical lure candidates (Kasetsart University (KU)-lures) were tested for diurnal Aedes aegypti, nocturnal Culex quinquefasciatus and nocturnal Anopheles minimus, using the HITSS assay. Results showed species-specific different lure preferences; the diurnal species were attracted to KU-lure #1 (29.7%), while both of the nocturnal species preferred KU-lure #6 (68.3% and 74.3% for Cx. quinquefasciatus and An. minimus, respectively). In addition, the selected lure candidates clearly demonstrated dose-dependent reversal responses for each Ae. aegypti and Cx. quinquefasciatus. Our results indicate that the HITSS assay distinguishes potential species-specific lure candidates. In addition, the HITSS assay was equally effective in determining the host-seeking behavior in pyrethroid-resistant and -susceptible strains. Further studies are needed to determine the accuracy of the HITSS assay in large-scale semi-field screen house tests using commercial traps.Several types of olfactometers have been used to evaluate mosquito responses to agents that mimic natural volatiles that repel or attract. The Y-tube olfactometer has been widely used to study repellents and attractants, while the high-throughput screening system assay has only been used to study repellents. Whether the high-throughput screening system assay is suitable for evaluating attractants is unknown. We evaluated the responses to four lactic-acid-based mixtures and two non-lactic-acid-based chemical lure candidates using the high-throughput screening system (HITSS) for three mosquito species (laboratory strains and field populations of both Aedes aegypti (L.) and Culex quinquefasciatus Say.; laboratory strain of Anopheles minimus Theobald) under laboratory-controlled conditions. HITSS assay results showed that KU-lure #1 elicited the greatest percent attraction for pyrethroid-resistant and -susceptible Ae. aegypti. KU-lure #6 elicited the strongest attractive response for pyrethroid-susceptible and -resistant Cx. quinquefasciatus and pyrethroid-susceptible An. minimus. The response to the lures from each species was independent of the pyrethroid susceptibility status (Ae. aegypti, p = 0.825; Cx. quinquefasciatus, p = 0.056). However, a significant difference in attraction to KU-lure #6 was observed between diurnal and nocturnal mosquitoes (Cx. quinquefasciatus vs. Ae. aegypti, p = 0.014; An. minimus vs. Ae. aegypti, p = 0.001). The laboratory-level HITSS assay effectively selects potential lure candidates. Because the host-seeking behavior differs between mosquito species, further studies are needed to develop species-specific attractants. Additional studies in semi-field screen houses using commercial traps are necessary to evaluate the accuracy of these laboratory assay results.

First Insights into the Chemical Ecology of an Invasive Pest: Olfactory Preferences of the Viburnum Leaf Beetle (Coleoptera: Chrysomelidae).

The viburnum leaf beetle (VLB), Pyrrhalta viburni (Paykull), is an invasive chrysomelid in North America where it infests native Viburnum shrubs in woody areas and managed landscapes. Despite its invasive and destructive nature, little is known about the chemical ecology of this beetle, and efficient chemical lures for monitoring and trapping this insect have yet to be developed. Using two of the main host plants of VLB in its native range, Viburnum opulus L. (Caprifoliaceae) and V. lantana L., we examined the olfactory preferences of adult females of VLB under laboratory conditions and measured volatile emissions of Viburnum twigs with and without VLB damage. VLB females had a clear preference for V. opulus and V. lantana twigs compared to blank odor sources. In addition, twigs with foliar damage and fresh egg masses were found to be more attractive than noninfested twigs in V. opulus when VLB infestation was recent, but not when twigs had been infested for several weeks. Chemical analyses revealed consistent treatment-specific blends of compounds, which may be used for the elaboration of attractive lures. Future research should focus on the identification of these compounds and on exploring the olfactory preferences of VLB with Viburnum species present in North America.

Systematic Modification of Zingerone Reveals Structural Requirements for Attraction of Jarvis\u2019s Fruit Fly

Tephritid fruit flies are amongst the most significant horticultural pests globally and male chemical lures are important for monitoring and control. Zingerone has emerged as a unique male fruit fly lure that can attract dacine fruit flies that are weakly or non-responsive to methyl eugenol and cuelure. However, the key features of zingerone that mediate this attraction are unknown. As Jarvis’s fruit fly, Bactrocera jarvisi (Tryon), is strongly attracted to zingerone, we evaluated the response of B. jarvisi to 37 zingerone analogues in a series of field trials to elucidate the functional groups involved in attraction. The most attractive analogues were alkoxy derivatives, with isopropoxy being the most attractive, followed by ethoxy and trifluoromethoxy analogues. All of the phenolic esters tested were also attractive with the response typically decreasing with increasing size of the ester. Results indicate that the carbonyl group, methoxy group, and phenol of zingerone are key sites for the attraction of B. jarvisi and identify some constraints on the range of structural modifications that can be made to zingerone without compromising attraction. These findings are important for future work in developing and optimising novel male chemical lures for fruit flies.

A new synthetic lure for management of the invasive giant African snail, Lissachatina fulica.

Synthetic chemical lures mimicking pheromones or food attractants are essential tools in eradication programs for invasive species. However, their uses in programs aiming to control or eradicate terrestrial gastropods are largely unexplored. The goal of this study was to find a synthetic attractant that could aid in the eradication or management of the giant African snail (Lissachatina fulica). Field studies in Hawaii showed that a commercial papaya-flavored oil attracted snails. Analysis of the odor profile of the oil identified a total of 22 chemicals, which comprised > 98% of the volatile compounds emitted by the oil. A synthetic blend was reconstructed that mirrored the release rates of the papaya oil odors. In laboratory and field bioassays, the reconstructed blend, applied to cotton wicks as water and canola oil or water and mineral emulsions, attracted more snails than the water and oil emulsion control wicks. Field studies in Hawaii and Florida showed that the reconstructed blend in an oil emulsion was not attractive to non-target species such as butterflies or bees. The snails were attracted from distances > 1 m and entered traps baited with the attractant emulsion. When tested in the South Florida giant African snail eradication program, direct ground application of the reconstructed papaya-flavored oil emulsion increased the number of snails killed by over 87% compared to water emulsion controls. Integrating tactics using the synthetic papaya oil attractant into control measures should increase the effectiveness of eradication and management programs.

Efficacy of diurnal BG-Sentinel traps to capture nocturnal adult Armigeres subalbatus mosquitoes and impact of altitudinal variations in forests

Objective: To establish an efficacious and efficient surveillance method of Armigeres (Ar.) subalbatus, a known filarial vector, surviving in forest habitats to estimate realistic population density and assess the impact of altitudinal variations on the efficacy of the trap. Methods: In the study, 12 locations in areas with an altitudinal range from 82 m to 920 m were selected in three reserve forests for night sampling of adult Ar. subalbatus mosquito using standard chemical lure based BG-Sentinel traps and CDC-light traps in pairs. Effects of locations and time were estimated on the efficacy of traps as mosquito density using multifactor analysis of variance for significant differences. Impact of altitudinal variations on the efficacy of traps was assessed using multiple regression with slope comparison. Results: BG-Sentinel trap collected significantly more adult Ar. subalbatus, 4.43 folds in Gorumara NP, 5.19 folds in Neora Valley NP and 12.10 folds in Mahananda WLS than the CDC-light trap irrespective to locations. BG-Sentinel traps were tolerant of altitudinal variations (80 m -170 m) and showed no significant relationship between density and altitudes in contrast to CDC-light traps which showed a significant negative impact on capturing efficacy with increase in altitudes (P Conclusions: The study suggests that BG-Sentinel traps can be used effectively and efficiently to collect more Ar. subalbatus mosquitoes during night time in comparison to CDC-light trap under complex climatic conditions of forest and variable altitudes.