A larval aggregation pheromone as foraging cue for insectivorous birds.

Although birds have traditionally been considered anosmic, increasing evidence indicates that olfaction plays an important role in the foraging behaviours of insectivorous birds. Recent studies have shown that birds can exploit herbivore-induced plant volatiles and sexual pheromones of adult insects to locate their prey. Many insectivorous birds prey on immature insects, providing relevant ecosystem services as pest regulators in natural and agricultural ecosystems. We asked whether birds could rely on chemical cues emitted by the immature stages of insects to prey on them. To address this question, we performed field experiments to evaluate if insectivorous birds can detect the aggregation pheromone produced by the larvae of the carpenter worm, Chilecomadia valdiviana. Groups of five artificial larvae were placed in branches of 72 adult trees in a remnant fragment of a sclerophyllous forest in central Chile. Each grouping of larvae contained a rubber septum loaded with either larval pheromone as treatment or solvent alone as control. We found that the number of larvae damaged by bird pecks was significantly higher in groups with dispensers containing the larval extract than in control groups. Our results show that birds can rely on immature insect-derived chemical cues used for larvae aggregation to prey on them.

Efficacy of aggregation nano gel pheromone traps on the catchability of Rhynchophorus ferrugineus (Olivier) in Egypt / Eficácia das armadilhas de feromônio de nano gel de agregação na capturabilidade de Rhynchophorus ferrugineus (Olivier) no Egito

Field experiments were carried out in the reclaimed land east of Cairo-Alexandria Desert Road, Village of Wardan, Giza Governorate, Egypt, to evaluate the impact of using nano-gels pheromone for the first time on the attraction of the RPW adults by pheromone traps compared to the control which is normal pheromone during two successive seasons in 2018 and 2019. Also, this study aimed to compare the efficacy of two types of trap, traditional trap (type 1) and dry funnel trap (type 2) in capturing of RPW adults. Results revealed that the nano gel pheromone traps attracted significantly more adults with an average of (4.26 and 3.56) adults/trap and total of (55.33 and 46.33) adults/trap compared to control with an average (2.69 and 2.46) and total of (35.00 and 32.00) adults/trap for the two seasons 2018 and 2019 respectively. Results indicated that the use of nano gel pheromone for the first time in field improved the trap catchability to RPW adults by 22.51 and 18.30% of total number of RPW adults captured throw out the two successive seasons respectively. In addition, there was no significant difference between the total numbers of RPW adults collected by the two tested type of traps over the two successive seasons. Furthermore, the sex ratio between males and females of total collected RPW adults found to be1: 1.43 and 1: 1.94 at 2018 and 2019 respectively.(AU)

Experimentos de campo foram realizados na terra recuperada a leste da estrada do deserto de Cairo-Alexandria, vila de Wardan, província de Giza, Egito, para avaliar o impacto do uso de feromônio de nano géis pela primeira vez na atração de adultos RPW por armadilhas de feromônio comparado ao controle que é o feromônio normal durante duas temporadas sucessivas em 2018 e 2019. Além disso, este estudo teve como objetivo comparar a eficácia de dois tipos de armadilha, armadilha tradicional (tipo 1) e armadilha de funil seco (tipo 2) na captura de RPW adultos. Os resultados revelaram que as armadilhas de nano gel de feromônio atraíram significativamente mais adultos, com uma média de (4,26 e 3,56) adultos/armadilha e total de (55,33 e 46,33) adultos/armadilha em comparação ao controle com uma média (2,69 e 2,46) e total de (35.00 e 32.00) adultos/armadilha para as duas temporadas 2018 e 2019, respectivamente. Os resultados indicaram que o uso de feromônio nano gel pela primeira vez em campo melhorou a capturabilidade de armadilhas para adultos com RPW em 22,51 e 18,30% do número total de adultos com RPW capturados durante as duas estações sucessivas, respectivamente. Além disso, não houve diferença significativa entre o número total de adultos RPW coletados pelos dois tipos de armadilhas testados ao longo das duas estações sucessivas. Além disso, a proporção sexual entre homens e mulheres do total de adultos coletados de RPW foi de 1: 1,43 e 1: 1,94 em 2018 e 2019, respectivamente.(AU)

Insecticide-impregnated netting: A surface treatment for killing Lutzomyia longipalpis (Diptera: Psychodidae), the vector of Leishmania infantum.

The sand fly Lutzomyia longipalpis is the main vector of Leishmania infantum in Brazil. Synthetic male-produced sex/aggregation pheromone co-located with micro-encapsulated λ-cyhalothrin in chicken sheds can significantly reduce canine infection and sand fly densities in a lure-and-kill strategy. In this study, we determined if insecticide-impregnated netting (IN) could replace insecticide residual spraying (IRS). We compared numbers of Lu. longipalpis attracted and killed in experimental and real chicken sheds baited with pheromone and treated with a 1 m2 area of either insecticide spray or netting. First, we compared both treatments in experimental sheds to control mortality established from light trap captures. We then compared the long-term killing effect of insecticide spray and netting, without renewal, in experimental sheds over a period of 16 weeks. Finally, a longitudinal intervention study in real chicken sheds compared the numbers and proportions of Lu. longipalpis collected and killed before and after application of both treatments. In Experiment 1, a higher proportion of males and females captured in IRS- and IN-treated sheds were dead at 24 h compared to controls (P < 0.05). No difference was found in the proportion of females killed in sheds treated with IN or IRS (P = 0.15). A slightly higher proportion of males were killed by IRS (100%) compared to IN (98.6%; P < 0.05). In Experiment 2, IN- and IRS-treated traps were equally effective at killing females (P = 0.21) and males (P = 0.08). However, IRS killed a significantly higher proportion of females and males after 8 (P < 0.05) and 16 (P < 0.05) weeks. In Experiment 3, there was no significant difference between treatments in the proportion of females killed before (P = 0.88) or after (P = 0.29) or males killed before (P = 0.76) or after (P = 0.73) intervention. Overall, initially the IN was as effective as IRS at killing female and male Lu. longipalpis in both experimental and real chicken sheds. However, the relative lethal effect of the IN deteriorated over time when stored under prevailing environmental conditions.

Efficacy of aggregation nano gel pheromone traps on the catchability of Rhynchophorus ferrugineus (Olivier) in Egypt / Eficácia das armadilhas de feromônio de nano gel de agregação na capturabilidade de Rhynchophorus ferrugineus (Olivier) no Egito

Field experiments were carried out in the reclaimed land east of Cairo-Alexandria Desert Road, Village of Wardan, Giza Governorate, Egypt, to evaluate the impact of using nano-gels pheromone for the first time on the attraction of the RPW adults by pheromone traps compared to the control which is normal pheromone during two successive seasons in 2018 and 2019. Also, this study aimed to compare the efficacy of two types of trap, traditional trap (type 1) and dry funnel trap (type 2) in capturing of RPW adults. Results revealed that the nano gel pheromone traps attracted significantly more adults with an average of (4.26 and 3.56) adults/trap and total of (55.33 and 46.33) adults/trap compared to control with an average (2.69 and 2.46) and total of (35.00 and 32.00) adults/trap for the two seasons 2018 and 2019 respectively. Results indicated that the use of nano gel pheromone for the first time in field improved the trap catchability to RPW adults by 22.51 and 18.30% of total number of RPW adults captured throw out the two successive seasons respectively. In addition, there was no significant difference between the total numbers of RPW adults collected by the two tested type of traps over the two successive seasons. Furthermore, the sex ratio between males and females of total collected RPW adults found to be1: 1.43 and 1: 1.94 at 2018 and 2019 respectively.

Experimentos de campo foram realizados na terra recuperada a leste da estrada do deserto de Cairo-Alexandria, vila de Wardan, província de Giza, Egito, para avaliar o impacto do uso de feromônio de nano géis pela primeira vez na atração de adultos RPW por armadilhas de feromônio comparado ao controle que é o feromônio normal durante duas temporadas sucessivas em 2018 e 2019. Além disso, este estudo teve como objetivo comparar a eficácia de dois tipos de armadilha, armadilha tradicional (tipo 1) e armadilha de funil seco (tipo 2) na captura de RPW adultos. Os resultados revelaram que as armadilhas de nano gel de feromônio atraíram significativamente mais adultos, com uma média de (4,26 e 3,56) adultos/armadilha e total de (55,33 e 46,33) adultos/armadilha em comparação ao controle com uma média (2,69 e 2,46) e total de (35.00 e 32.00) adultos/armadilha para as duas temporadas 2018 e 2019, respectivamente. Os resultados indicaram que o uso de feromônio nano gel pela primeira vez em campo melhorou a capturabilidade de armadilhas para adultos com RPW em 22,51 e 18,30% do número total de adultos com RPW capturados durante as duas estações sucessivas, respectivamente. Além disso, não houve diferença significativa entre o número total de adultos RPW coletados pelos dois tipos de armadilhas testados ao longo das duas estações sucessivas. Além disso, a proporção sexual entre homens e mulheres do total de adultos coletados de RPW foi de 1: 1,43 e 1: 1,94 em 2018 e 2019, respectivamente.

Efficacy of aggregation nano gel pheromone traps on the catchability of Rhynchophorus ferrugineus (Olivier) in Egypt

Abstract Field experiments were carried out in the reclaimed land east of Cairo-Alexandria Desert Road, Village of Wardan, Giza Governorate, Egypt, to evaluate the impact of using nano-gels pheromone for the first time on the attraction of the RPW adults by pheromone traps compared to the control which is normal pheromone during two successive seasons in 2018 and 2019. Also, this study aimed to compare the efficacy of two types of trap, traditional trap (type 1) and dry funnel trap (type 2) in capturing of RPW adults. Results revealed that the nano gel pheromone traps attracted significantly more adults with an average of (4.26 and 3.56) adults/trap and total of (55.33 and 46.33) adults/trap compared to control with an average (2.69 and 2.46) and total of (35.00 and 32.00) adults/trap for the two seasons 2018 and 2019 respectively. Results indicated that the use of nano gel pheromone for the first time in field improved the trap catchability to RPW adults by 22.51 and 18.30% of total number of RPW adults captured throw out the two successive seasons respectively. In addition, there was no significant difference between the total numbers of RPW adults collected by the two tested type of traps over the two successive seasons. Furthermore, the sex ratio between males and females of total collected RPW adults found to be1: 1.43 and 1: 1.94 at 2018 and 2019 respectively.

Resumo Experimentos de campo foram realizados na terra recuperada a leste da estrada do deserto de Cairo-Alexandria, vila de Wardan, província de Giza, Egito, para avaliar o impacto do uso de feromônio de nano géis pela primeira vez na atração de adultos RPW por armadilhas de feromônio comparado ao controle que é o feromônio normal durante duas temporadas sucessivas em 2018 e 2019. Além disso, este estudo teve como objetivo comparar a eficácia de dois tipos de armadilha, armadilha tradicional (tipo 1) e armadilha de funil seco (tipo 2) na captura de RPW adultos. Os resultados revelaram que as armadilhas de nano gel de feromônio atraíram significativamente mais adultos, com uma média de (4,26 e 3,56) adultos/armadilha e total de (55,33 e 46,33) adultos/armadilha em comparação ao controle com uma média (2,69 e 2,46) e total de (35.00 e 32.00) adultos/armadilha para as duas temporadas 2018 e 2019, respectivamente. Os resultados indicaram que o uso de feromônio nano gel pela primeira vez em campo melhorou a capturabilidade de armadilhas para adultos com RPW em 22,51 e 18,30% do número total de adultos com RPW capturados durante as duas estações sucessivas, respectivamente. Além disso, não houve diferença significativa entre o número total de adultos RPW coletados pelos dois tipos de armadilhas testados ao longo das duas estações sucessivas. Além disso, a proporção sexual entre homens e mulheres do total de adultos coletados de RPW foi de 1: 1,43 e 1: 1,94 em 2018 e 2019, respectivamente.

Susceptibility of wild-caught Lutzomyia longipalpis (Diptera: Psychodidae) sand flies to insecticide after an extended period of exposure in western São Paulo, Brazil.

BACKGROUND: In Brazil, members of the sand fly species complex Lutzomyia longipalpis transmit Leishmania infantum, a protist parasite that causes visceral leishmaniasis. Male Lu. longipalpis produce a sex pheromone that is attractive to both females and males. During a cluster randomised trial, to determine the combined effect of synthetic sex-aggregation pheromone and insecticide on Le. infantum transmission Lu. longipalpis had been continuously exposed to insecticide for 30 months. The objective of this study was to determine the effect of continuous exposure to the insecticides used in the trial on the susceptibility of Lu. longipalpis population. METHODS: During the trial the sand flies had been exposed to either lambda-cyhalothrin [pheromone + residual insecticide spray (PI)], deltamethrin [dog collars (DC)] or no insecticide [control (C)], for 30 months (November 2012 to April 2015). The insecticide treatment regime was kept in place for an additional 12 months (May 2015-April 2016) during this susceptibility study. Sand flies collected from the field were exposed to WHO insecticide-impregnated papers cyhalothrin (0.05%), deltamethrin (0.5%) and control (silicone oil) in a modified WHO insecticide exposure trial to determine their susceptibility. RESULTS: We collected 788 Lu. longipalpis using CDC-light traps in 31 municipalities across the three trial arms. Probit analysis showed that the knockdown times (KDTs) of Lu. longipalpis collected from the lambda-cyhalothrin exposed PI-arm [KDT50: 31.1 min, confidence interval (CI): 29.6-32.6 and KDT90: 44.2 min, CI: 42.1-46.7] were longer than the KDTs from the non-insecticide-treated C-arm (KDT50: 26.3 min, CI: 25.1-27.6 and KDT90: 38.2, CI: 36.5-40.2) (no-overlapping 95% CIs). KDTs of Lu. longipalpis collected from the deltamethrin exposed DC-arm had similar values (KDT50: 13.7 min, CI: 10.1-16.2 and KDT90: 26.7 min, CI: 21.8-30.6) to those for the C-arm (KDT50: 13.5 min; CI: 12.2-14.8 and KDT90: 23.2 min, CI: 21.4-25.4) (overlapping CIs). The wild-caught unexposed Lu. longipalpis (C-arm), took approximately twice as long to knock down as laboratory-colonised specimens for both insecticides. CONCLUSIONS: Our study reveals slight changes in KDT, in sand flies after prolonged exposure to lambda-cyhalothrin in the presence of pheromone. These changes are not considered to have reached the reference levels indicative of resistance in sand flies suggesting that pheromone and insecticide treatment at the level indicated in this study do not constitute a significant risk of increased insecticide resistance. Prolonged exposure to deltamethrin in dog collars did not result in changes to KDT.

Development of pull and push-pull systems for management of lesser mealworm, Alphitobius diaperinus, in poultry houses using alarm and aggregation pheromones.

BACKGROUND: The lesser mealworm, Alphitobius diaperinus (Coleoptera: Tenebrionidae), is the most important insect pest affecting poultry production around the world, with all life stages being susceptible to infection by bacteria, viruses and fungi. Control of A. diaperinus in poultry houses using intensive insecticide application is not effective due to the cryptic behaviour of this pest. Here, we evaluated the potential of recently identified A. diaperinus alarm (1,4-benzoquinone, 2-methyl-1,4-benzoquinone and 2-ethyl-1,4-benzoquinone) and aggregation [(R)-limonene, 2-nonanone, (E)-ocimene, (S)-linalool, (R)-daucene and (E,E)-α-farnesene] pheromones as tools for the management of this pest in poultry houses in Brazil. RESULTS: Laboratory arena assays with synthetic alarm pheromone confirmed A. diaperinus repellency. In an initial field assay, traps baited with synthetic aggregation pheromone captured significantly more insects than control traps. In further field assays that compared a pull (aggregation pheromone) and a push-pull (simultaneous alarm/aggregation pheromone deployment) system, a higher number of A. diaperinus were captured in aggregation pheromone-baited traps in the push-pull system. CONCLUSION: Our results suggest that alarm and aggregation pheromones can be deployed in poultry houses to trap significant numbers of adult A. diaperinus. Studies are underway to determine the potential for using these components as part of an integrated A. diaperinus management strategy. © 2018 Society of Chemical Industry.

Factors Influencing Mating Behavior and Success in the Red Palm Weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Dryophthoridae).

The effects of body size, age, feeding and mating status, conspecific volatiles from live adults, synthetic aggregation pheromone, and a pheromone synergist, ethyl acetate, on the mating behavior of red palm weevil, Rhynchophorus ferrugineus Olivier, were investigated. To evaluate these factors, variables such as mating latency, frequency and duration, and refractory period were assessed. While both, body size and age, influenced the mating behavior, the latter showed a stronger effect. The large males recorded frequent and longer matings, whereas the young males outperformed the old weevils in all the studied variables. The difference in body size or age of females showed a limited effect. After 72 h without food, the males showed a significant decline in mating frequency and duration, and refractory period. Mating status showed comparatively stronger effects on mating variables. In the case of females, mating status emerged as the most important factor affecting four out of five variables. The volatiles from the males, grouped males and females, and synthetic aggregation pheromone both alone and in combination with ethyl acetate triggered mating initiation, propelled mating frequency, prolonged total mating duration, and reduced the refractory period. However, the presence of females or ethyl acetate alone was a weak mating stimulator.

Efficacy of aggregation nano gel pheromone traps on the catchability of Rhynchophorus ferrugineus (Olivier) in Egypt

Abstract Field experiments were carried out in the reclaimed land east of Cairo-Alexandria Desert Road, Village of Wardan, Giza Governorate, Egypt, to evaluate the impact of using nano-gels pheromone for the first time on the attraction of the RPW adults by pheromone traps compared to the control which is normal pheromone during two successive seasons in 2018 and 2019. Also, this study aimed to compare the efficacy of two types of trap, traditional trap (type 1) and dry funnel trap (type 2) in capturing of RPW adults. Results revealed that the nano gel pheromone traps attracted significantly more adults with an average of (4.26 and 3.56) adults/trap and total of (55.33 and 46.33) adults/trap compared to control with an average (2.69 and 2.46) and total of (35.00 and 32.00) adults/trap for the two seasons 2018 and 2019 respectively. Results indicated that the use of nano gel pheromone for the first time in field improved the trap catchability to RPW adults by 22.51 and 18.30% of total number of RPW adults captured throw out the two successive seasons respectively. In addition, there was no significant difference between the total numbers of RPW adults collected by the two tested type of traps over the two successive seasons. Furthermore, the sex ratio between males and females of total collected RPW adults found to be1: 1.43 and 1: 1.94 at 2018 and 2019 respectively.

Resumo Experimentos de campo foram realizados na terra recuperada a leste da estrada do deserto de Cairo-Alexandria, vila de Wardan, província de Giza, Egito, para avaliar o impacto do uso de feromônio de nano géis pela primeira vez na atração de adultos RPW por armadilhas de feromônio comparado ao controle que é o feromônio normal durante duas temporadas sucessivas em 2018 e 2019. Além disso, este estudo teve como objetivo comparar a eficácia de dois tipos de armadilha, armadilha tradicional (tipo 1) e armadilha de funil seco (tipo 2) na captura de RPW adultos. Os resultados revelaram que as armadilhas de nano gel de feromônio atraíram significativamente mais adultos, com uma média de (4,26 e 3,56) adultos/armadilha e total de (55,33 e 46,33) adultos/armadilha em comparação ao controle com uma média (2,69 e 2,46) e total de (35.00 e 32.00) adultos/armadilha para as duas temporadas 2018 e 2019, respectivamente. Os resultados indicaram que o uso de feromônio nano gel pela primeira vez em campo melhorou a capturabilidade de armadilhas para adultos com RPW em 22,51 e 18,30% do número total de adultos com RPW capturados durante as duas estações sucessivas, respectivamente. Além disso, não houve diferença significativa entre o número total de adultos RPW coletados pelos dois tipos de armadilhas testados ao longo das duas estações sucessivas. Além disso, a proporção sexual entre homens e mulheres do total de adultos coletados de RPW foi de 1: 1,43 e 1: 1,94 em 2018 e 2019, respectivamente.

The Lutzomyia longipalpis complex: a brief natural history of aggregation-sex pheromone communication.

In this paper we review the natural history of pheromone communication and the current diversity of aggregation-sex pheromones in the sand fly Lutzomyia longipalpis. This species complex is the main vector of Leishmania infantum, the agent of visceral leishmaniasis in the Americas. The identification of variation in pheromone chemotypes combined with molecular and sound analyses have all contributed to our understanding of the extent of divergence among cryptic members of this complex. The importance of chemical signals as pre-mating barriers and drivers of speciation is discussed. Moreover, the importance of aggregation-sex pheromones as sexually selected signals is highlighted with evidence from the literature suggesting their potential role in species and mate recognition as well as mate assessment. The distinct evolutionary forces possibly involved are briefly reviewed and discussed in the context of this intriguing insect.

Revisiting the Male-Produced Aggregation Pheromone of the Lesser Mealworm, Alphitobius diaperinus (Coleoptera, Tenebrionidae): Identification of a Six-Component Pheromone from a Brazilian Population.

The lesser mealworm, Alphitobius diaperinus Panzer 1797 (Coleoptera: Tenebrionidae), is a cosmopolitan insect pest affecting poultry production. Due to its cryptic behavior, insecticide control is usually not efficient. Thus, sustainable and effective methods would have an enormous and positive impact in poultry production. The aim of this study was to confirm the identity of the male-produced aggregation pheromone for a Brazilian population of A. diaperinus and to evaluate its biological activity in behavioral assays. Six male-specific compounds were identified: (R)-limonene (1), (E)-ocimene (2), 2-nonanone (3), (S)-linalool (4), (R)-daucene (5), all described before in an American population, and a sixth component, (E,E)-α-farnesene (6), which is apparently exclusive to a Brazilian population. Y-Tube bioassays confirmed the presence of a male-produced aggregation pheromone and showed that all components need to be present in a similar ratio and concentration as emitted by male A. diaperinus to produce a positive chemotactic response.

(6E,8Z)-6,8-Pentadecadienal, a Novel Attractant Pheromone Produced by Males of the Cerambycid Beetles Chlorida festiva and Chlorida costata.

We report the identification, synthesis, and first field bioassays of a pheromone component with a novel structure produced by adult males of Chlorida festiva (L.) and Chlorida costata Audinet-Serville, longhorn beetle species in the subfamily Cerambycinae. Headspace volatiles from males contained a sex-specific compound that was identified as (6E,8Z)-6,8-pentadecadienal. Traps baited with this compound captured adults of both species and sexes, consistent with the aggregation-sex pheromones produced by males of many species in this subfamily. This compound represents a new structural class of cerambycid pheromones, and it is the first pheromone identified from species in the tribe Bothriospilini.

(1R,2S,6R)-Papayanal: a new male-specific volatile compound released by the guava weevil Conotrachelus psidii (Coleoptera: Curculionidae).

The guava weevil, Conotrachelus psidii is an aggressive pest of guava (Psidium guajava L.) that causes irreparable damages inside the fruit. The volatile compounds of male and female insects were separately collected by headspace solid-phase microextraction or with dynamic headspace collection on a polymer sorbent, and comparatively analyzed by GC-MS. (1R,2S,6R)-2-Hydroxymethyl-2,6-dimethyl-3-oxabicyclo[4.2.0]octane (papayanol), and (1R,2S,6R)-2,6-dimethyl-3-oxabicyclo[4.2.0]octane-2-carbaldehyde (papayanal) were identified (ratio of 9:1, respectively) as male-specific guava weevil volatiles. Papayanal structure was confirmed by comparison of spectroscopic (EIMS) and chromatographic (retention time) data with those of the synthetic pure compound. The behavioral response of the above-mentioned compounds was studied in a Y-tube olfactometer bioassay, and their role as aggregation pheromone candidate components was suggested in this species.