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BACKGROUND: Populations of the plant pathogenic fungus Verticillium dahliae display a complex and rich genetic diversity, yet the existence of sexual reproduction in the fungus remains contested. As pivotal genes, MAT genes play a crucial role in regulating cell differentiation, morphological development, and mating of compatible cells. However, the functions of the two mating type genes in V. dahliae, VdMAT1-1-1, and VdMAT1-2-1, remain poorly understood. RESULTS: In this study, we confirmed that the MAT loci in V. dahliae are highly conserved, including both VdMAT1-1-1 and VdMAT1-2-1 which share high collinearity. The conserved core transcription factor encoded by the two MAT loci may facilitate the regulation of pheromone precursor and pheromone receptor genes by directly binding to their promoter regions. Additionally, peptide activity assays demonstrated that the signal peptide of the pheromone VdPpg1 possessed secretory activity, while VdPpg2, lacked a predicted signal peptide. Chemotactic growth assays revealed that V. dahliae senses and grows towards the pheromones FO-a and FO-α of Fusarium oxysporum, as well as towards VdPpg2 of V. dahliae, but not in response to VdPpg1. The findings herein also revealed that VdMAT1-1-1 and VdMAT1-2-1 regulate vegetative growth, carbon source utilization, and resistance to stressors in V. dahliae, while negatively regulating virulence. CONCLUSIONS: These findings underscore the potential roles of VdMAT1-1-1 and VdMAT1-2-1 in sexual reproduction and confirm their involvement in various asexual processes of V. dahliae, offering novel insights into the functions of mating type genes in this species.

Amongst all Enterococcus spp., E. faecalis and E. faecium are most known notorious pathogen and their biofilm formation has been associated with endocarditis, oral, urinary tract, and wound infections. Biofilm formation involves a pattern of initial adhesion, microcolony formation, and mature biofilms. The initial adhesion and microcolony formation involve numerous surface adhesins e.g. pili Ebp and polysaccharide Epa. The mature biofilms are maintained by eDNA, It’s worth noting that phage-mediated dispersal plays a prominent role. Further, the involvement of peptide pheromones in regulating biofilm maintenance sets it apart from other pathogens and facilitating the horizontal transfer of resistance genes. The role of fsr based regulation by regulating gelE expression is also discussed. Thus, we provide a concise overview of the significant determinants at each stage of Enterococcus spp. biofilm formation. These elements could serve as promising targets for antibiofilm strategies. [ABSTRACT FROM AUTHOR]

Collective behaviors of social insects are often regulated by pheromones. In subterranean termites, some workers forage for and exploit decaying wood for new food resources while forming tunnels from their nest. Colonizing new food resources requires workers to build and disinfect tunnels and chambers inside the nest and ingest decaying wood; therefore subterranean termite colonies should have mechanisms to establish and maintain groups of workers to perform these functions. Recently, an aggregation pheromone was identified in workers of the termite Reticulitermes speratus, which induces quick attraction of nestmate workers and prolonged aggregation to the site of attraction. In this study, we extended this work to another species of Reticulitermes and identified a worker aggregation pheromone in the termite R. virginicus. GC–MS analysis and bioassays demonstrated that this pheromone consists of 3-octanone, 3-octanol, and palmitic acid and shows a colony-specific, dose-dependent attractant response but not an arrestant response. Furthermore, these pheromone components were most likely emitted from the surface of the body. This suggests that aggregation pheromone composition and function differ significantly among termite species, even within the same genus. This study advances our understanding of the regulatory mechanisms of termite aggregation behavior. [ABSTRACT FROM AUTHOR]

Same-sex sexual behavior (SSB) is an enigma in behavioral ecology as it does not result in reproduction. Proximately, the effect of sexual signals on SSB could be distinct between signal receivers and senders. For receivers, the absence of sexual signals leads to smaller phenotypic sex differences, leading to frequent accidental SSB between receivers. Alternatively, for senders, sexual signals could help locate another sender, enhancing intentional SSB. Here, we demonstrate this link between sex pheromone signaling and the frequency of same-sex pairing in two Coptotermes termites that use the same chemical as sex pheromones but in different quantities. In termites, mating pairs engage in tandem runs, where a female emits sex pheromones to guide a male as they move together in searching a potential nest site. So, females are signal senders, and males are signal receivers for sexual communication. We found that female-female tandems were more stable in C. formosanus, whose females produce more pheromones. On the other hand, although both species did not show stable male–male tandems, males of C. gestroi , whose females produce fewer pheromones, spent more time attempting to follow another male. Thus, stronger pheromones lead to sender–sender SSB, while weaker pheromones lead to receiver–receiver SSB. The proximate mechanism of SSB is diverse according to the properties of sexual communications in heterosexual contexts. [ABSTRACT FROM AUTHOR]

Simple Summary: The main aim of this study was to identify antennally active pheromone components from the citrus long-horned beetle, Anoplophora chinensis, and to test them for behavioral activity. We identified three antennally active male-produced chemical components (nonanal, 4-(n-heptyloxy)butan-1-ol, and 4-(n-heptyloxy)butanal). When tested together in Y-tube behavioral assays, these three compounds were shown to be attractive to adult female A. chinensis. Pheromone production and behavior of A. chinensis are discussed in relation to other closely related Anoplophora cerambycid species. The citrus long-horned beetle, Anoplophora chinensis (Coleoptera: Cerambycidae), is a highly polyphagous species native to eastern and southeastern Asia. Detection of these beetles is dependent on visual surveys, which are inefficient and labor-intensive. The identification and development of pheromone-based lures would help improve survey efforts for A. chinensis should it become established within the US. We identified three antennally active male-produced chemical components (nonanal, 4-(n-heptyloxy)butan-1-ol, and 4-(n-heptyloxy)butanal), which were then tested for behavioral activity at our USDA Quarantine laboratory. When tested together in Y-tube behavioral assays, a three-component blend of the identified compounds was shown to be attractive to adult female A. chinensis. Pheromone production and behavior of A. chinensis and other closely related Anoplophora cerambycid species are discussed in relation to mate finding and potential monitoring. [ABSTRACT FROM AUTHOR]

Death feigning is hypothesized to be an anti-predator behavior in which prey is temporarily immobilized in response to external stimuli. While death feigning may be an effective predator-defense strategy, there may be trade-offs in terms of energy and time for finding food and/or mating. The duration of death feigning is regulated by the balance of various selection pressures, and its duration is influenced by many internal and environmental factors. However, little is known about the factors that influence arousal from death-feigning behavior. Sex pheromones are important semiochemicals that affect reproductive success and may influence the duration of death-feigning behavior. In this study, we aimed to investigate the effects of sex pheromones on the death-feigning behavior of the sweet potato weevil (Cylas formicarius) by conducting laboratory experiments. The results showed that males had a significantly shorter death-feigning duration in the presence of sex pheromones because it aroused them from their death-feigning behavior, but females were unaffected. This is the first study to show that sex pheromones alter death-feigning behavior. The results of this study elucidate the factors influencing predator-avoidance behavior and reveal the impact of death-feigning behavior on prey reproduction under predation pressure. [ABSTRACT FROM AUTHOR]

Females' ability to select mates that can fertilize eggs directly impacts their fitness, but the secondary sexual traits that often guide mate choice may not be directly correlated with male fertility. In externally fertilizing species, such as many fish species, chemical cues in ejaculates may allow females to assess male fertilization capacity. However, chemical cues associated with sperm release have only been described in a few species, and evidence that females use these cues to discriminate among males remains limited. Female sea lamprey, Petromyzon marinus , use several chemical cues to find and interact with potential mates, including a sex pheromone released by males across their gill epithelia and a second sex pheromone released in their semen. Unlike males of many fish species that control pheromone release via urinary pulses, male sea lamprey continually broadcast the gill pheromone once they are sexually mature. This presents a potentially costly scenario for females because attraction to males that are not actively spawning or that are sperm-depleted likely wastes time and energy. We tested the hypothesis that female sea lamprey use pheromones present in seminal plasma to discriminate among potential mates. In-stream behavioural assays revealed that females (1) preferred seminal plasma + male-conditioned water (containing gill-released pheromones) over male-conditioned water alone, (2) preferred male-conditioned water + 2× seminal plasma over male-conditioned water + 1× seminal plasma and (3) oriented towards seminal plasma over large distances and when no male-conditioned water was applied. Taken together, our results indicate that female sea lamprey use seminal pheromones to find and remain near males with immediate fertilization capacity, thereby reducing the risk of wasting time and energy during their single, reproductive window. Finally, our study highlights the importance of multiple cues in mate choice. • We tested whether seminal pheromones provide cues to female lamprey about male status. • Females discriminated males based on the presence of seminal pheromones. • Females discriminated males based on the concentration of seminal pheromones. • Seminal pheromones are a potent, independent cue in sea lamprey. [ABSTRACT FROM AUTHOR]

Background: Helopeltis cinchonae (Hemiptera: Miridae) is a major pest of tea plantations in Asia. Conventional control of pests with pesticides is unsustainable. Therefore, safe and eco‐friendly alternatives, such as pheromones, are required to manage the pest. Results: In gas chromatography–electroantennographic detection (GC–EAD) analysis of whole‐body extracts of virgin female H. cinchonae, two compounds elicited electroantennogram (EAG) responses from male antennae. These were identified as hexyl (R)‐3‐acetoxybutyrate and (R)‐1‐acetoxy‐5‐butyroxyhexane using gas chromatography–mass spectrometry (GC–MS) analysis compared to synthetic compounds. This is the first study to report 1‐acetoxy‐5‐butyroxyhexane as an insect pheromone component. The synthetic compounds elicited dose‐dependent EAG responses from the antennae of male H. cinchonae. In two field trapping experiments, the individual compounds were highly attractive to male H. cinchonae when dispensed from polyethylene vials. However, higher catches were obtained with blends of the two compounds in a 1:10 ratio. The blend of racemic compounds was as attractive as the blend of (R)‐enantiomers. Conclusions: We reported that 1‐acetoxy‐5‐butyroxyhexane and hexyl 3‐acetoxybutyrate are components of the female‐produced sex pheromone of H. cinchonae, but further work is required on the blend and loading of pheromone and on trap design to provide an optimized system for monitoring and control of this pest. The results may also facilitate the identification of the pheromones of other Helopeltis species, which are major pests in many crops. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Abstract Collective behaviors of social insects are often regulated by pheromones. In subterranean termites, some workers forage for and exploit decaying wood for new food resources while forming tunnels from their nest. Colonizing new food resources requires workers to build and disinfect tunnels and chambers inside the nest and ingest decaying wood; therefore subterranean termite colonies should have mechanisms to establish and maintain groups of workers to perform these functions. Recently, an aggregation pheromone was identified in workers of the termite Reticulitermes speratus, which induces quick attraction of nestmate workers and prolonged aggregation to the site of attraction. In this study, we extended this work to another species of Reticulitermes and identified a worker aggregation pheromone in the termite R. virginicus. GC–MS analysis and bioassays demonstrated that this pheromone consists of 3-octanone, 3-octanol, and palmitic acid and shows a colony-specific, dose-dependent attractant response but not an arrestant response. Furthermore, these pheromone components were most likely emitted from the surface of the body. This suggests that aggregation pheromone composition and function differ significantly among termite species, even within the same genus. This study advances our understanding of the regulatory mechanisms of termite aggregation behavior.

The current study investigated the structure and function of the olfactory system of the Lusitanian toadfish, Halobatrachus didactylus, using histology and electrophysiology (electro‐olfactogram [EOG]), respectively. The olfactory system consists of a digitated anterior peduncle, of unknown function, containing the inhalant nostril. This then leads to a U‐shaped olfactory chamber with the olfactory epithelium—identified by Gαolf‐immunoreactivity—on the ventral surface. A large lacrimal sac is connected to this tube and is likely involved in generating water movement through the olfactory chamber (this species is largely sedentary). The exhalent nostril lies by the eye and is preceded by a bicuspid valve to ensure one‐way flow of water. As do other teleosts, H. didactylus had olfactory sensitivity to amino acids and bile acids. Large‐amplitude EOG responses were evoked by fluid from the anterior and posterior testicular accessory glands, and bile and intestinal fluids. Anterior gland and intestinal fluids from reproductive males were significantly more potent than those from non‐reproductive males. Male urine and skin mucus proved to be the least potent body fluids tested. These results suggest that chemical communication—as well as acoustic communication—may be important in the reproduction of this species and that this may be mediated by the accessory glands and intestinal fluid. [ABSTRACT FROM AUTHOR]

The present study was carried out to determine the chemistry of the preputial gland (PG) of mature male black rats and its role in sexual and social communication. 50% PG extracts from male rats of different age groups were prepared using n-hexane and dichloromethane and tested against black rats of different age groups and sexes. Results revealed that mature females were highly attracted towards and mature males were highly repelled from preputial gland extract of mature male rats for five and two days, respectively. Comparison of gas chromatography linked mass spectrometry analysis of fresh and eight days old PG extract revealed that 13 pheromonal compounds (.+/-.)-.alpha.-tocopherol acetate; acetophenone; undecane; dodecane; tridecane; tetradecane; heneicosane; docosane; squalene; cholesterol; octadecanal; palmitic acid; stigmastan-3,5-diene) were exclusively present in fresh extract but absent in eight days old preputial gland extract. These 13 compounds are already reported to have role in sexual and social communication in other mammals, insects and reptiles. They might be used by mature male rats for sexual and social communication. In the future, these identified compounds can be used in fixed proportions individually and in various combinations after testing their efficacy to develop a stable lure to increase the trappability and acceptability of antifertility agents and rodenticide-based baits for the management of black rats. [ABSTRACT FROM AUTHOR]

The object of this study is the process of image segmentation from the First Person View (FPV) of an unmanned aerial vehicle (UAV). The main hypothesis of the study assumes that the use of a simple ant algorithm could ensure the necessary quality of the segmented image. The segmentation method, unlike the known ones, takes into account the number of ants in the image, weight, initial amount and evaporation rate of the pheromone, the "greediness" of the algorithm and provides: – preliminary selection of individual channels of the Red-Green-Blue (RGB) color space; – preliminary placement of ants according to the uniform law; – determining the routes of ants; – taking into account the attractiveness of the route for each ant; – change (adjustment) in the concentration of ant pheromones; – calculation of the probability of movement (transition) of the ant on the movement route; – determination of the objective function at the j-th iteration and its minimization; – determining the coordinates of the route of movement (movement) of ants; – verification of the fulfillment of the stop condition; – determination of the best routes found by ants; – calculation of the brightness of the pixels of the segmented image in each channel of the RGB color space; – further combining the results of channel segmentation. An experimental study of image segmentation from UAV FPV based on a simple ant algorithm was conducted. The specified object of interest on the segmented image has a certain structure, unevenness of the contours, and can be further used for decoding, categorization, etc. Unlike the object of interest, the background ("garbage" objects) in the segmented image do not have a stable structure and can be further filtered out. It has been established that the segmented image by the known method based on the gradient module has a low contrast value, there are gaps in the segmented pixels of the object of interest. A segmented image using a method based on a simple ant algorithm is free from that drawback. [ABSTRACT FROM AUTHOR]

Male Ensatina eschscholtzii do not have a mental gland, a macrogland used by males during courtship that is considered an ancestral character of plethodontids. We tested whether males and females have nonmental courtship glands associated with the integument of the rostrum and mentum (chin). We found that both male and female E. eschscholtzii possess courtship-like integumentary glands (modified granular glands) in the upper labia extending dorsally along the rostrum and lower labia extending ventrally across the mental region. These glands are sexually dimorphic in size (larger in females) and react positively with periodic acid–Schiff. We hypothesize that these glands are involved in courtship through production of pheromones that may or may not be similar to pheromones produced in courtship glands of other plethodontid salamanders. These rostral glands are structurally and chemically unique in comparison with glands of the rostrum that empty along the length of nasolabial grooves (nasolabial glands) of Ensatina, which do not appear to be involved in pheromone production. Both females and males have relatively few traditional mucous glands throughout the skin in comparison with other species of plethodontids, although some clusters are identified at the anterior edges of the labia. [ABSTRACT FROM AUTHOR]

Simple Summary: This study aimed to investigate the function of the nuptial pad-secreted pheromone in anurans. By conducting transcriptome sequencing of the nuptial pads of the Yunnan pond frog, we obtained transcripts of protein pheromones that were highly expressed in the nuptial pads during the breeding season. These pheromones were homologous to the common frog amplexins and the plethodontid modulating factor (PMF) pheromone of urodeles. By means of recombinant protein expression, we obtained the single subtype of the pheromone and demonstrated its ability to shorten the duration of Yunnan pond frog pairing through behavioral experiments. The results of this study further confirm that urodeles and anurans share the PMF pheromone system. Additionally, this study validates the function of this pheromone in anurans for the first time, confirming that it serves similar functions as in urodeles, shortening the breeding process. Overall, this study provides a paradigm for exploring the function of pheromones in anurans. Chemical communication is an important mode of communication in the courtship and breeding processes of amphibians. In caudates, multiple components of sexual pheromones have been identified and functionally verified. One of these pheromone systems is plethodontid modulating factor (PMF). In anurans, the pheromone called amplexin was found in nuptial pads of ranids and was considered a member of the PMF system, yet its bio-function has not been tested. In this study, we obtained 18 amplexin transcript sequences from nuptial pads of Nidirana pleuraden (Amphibia, Ranidae) by transcriptome sequencing and found that the proteins translated by these transcripts are diversified, hydrophilic, and relatively stable. We also acquired a N. pleuraden amplexin isoform with the highest expression level in the transcriptome analysis through the prokaryotic expression system. Using two different animal behavioral experimental settings, we have tested the bio-function of the recombinant PMF protein (rPMF) in N. pleuraden's reproduction and found that the rPMF does not attract females but shortens the duration of amplexus significantly. This is the first study to verify the function of the PMF pheromone in Anura, indicating the pervasiveness of chemical communication during breeding in amphibians. [ABSTRACT FROM AUTHOR]

Fusaric acid (FA), a picolinic acid derivative, is a natural substance produced by a wide variety of fungal plant pathogens belonging to the Fusarium genus. As a metabolite, fusaric acid exerts several biological activities including metal chelation, electrolyte leakage, repression of ATP synthesis, and direct toxicity on plants, animals and bacteria. Prior studies on the structure of fusaric acid revealed a co-crystal dimeric adduct between FA and 9,10-dehydrofusaric acid. During an ongoing search for signaling genes differentially regulating FA production in the fungal pathogen Fusarium oxysporum (Fo), we found that mutants lacking pheromone expression have an increased production of FA compared to the wild type strain. Noteworthy, crystallographic analysis of FA extracted from Fo culture supernatants showed that crystals are formed by a dimeric form of two FA molecules (1:1 molar stoichiometry). Overall, our results suggest that pheromone signaling in Fo is required to regulate the synthesis of fusaric acid. [ABSTRACT FROM AUTHOR]

BACKGROUND: Montana accounts for approximately 45% of US dry pea production and the pea leaf weevil (PLW; Sitona lineatus (L.)) is the most common insect pest in this region. After crop emergence adult PLW feed on the foliage to mature and subsequently mate, and the soil‐dwelling larvae feed and develop on the nitrogen‐fixing root nodules. Producers commonly apply prophylactic insecticide treatments to the seed at planting as well as one or two post‐emergent insecticide sprays to control PLW damage. To develop alternative management strategies based on integrated pest management (IPM), this field study evaluated pulse crops grown in Montana for adult feeding preference and larval development. Ten different field pea varieties, along with two faba bean, lentil and chickpea varieties, were evaluated during the 2020 and 2021 field seasons at the Montana State University Arthur H. Post Agronomy Farm. RESULTS: Significant PLW pest pressure was observed within the research plots during both experimental years. Field pea and faba bean were preferred by the foliage feeding adult stage, with all but one variety averaging 39.2 to 86.3 average notches per plant. The pea variety Lifter was significantly preferred over all other comparisons, averaging 142.4 and 95.0 notches per plant in 2020 and 2021, respectively. Adult PLW feeding on lentil and chickpea was minimal, averaging 3.3 to 8.2 and 0.5 to 1.6 notches per plant, respectively. Numbers of larvae were highest on the roots of pea varieties, a known reproductive host, and almost nil on lentil and chickpea roots. Faba bean is also known as reproductive host, but, unexpectedly, larval populations were also low on the two faba bean varieties. CONCLUSIONS: The results from this study provide some limited evidence for alternative IPM strategies for field peas based on host plant tolerance or resistance within the range of varieties tested. Adult preference and larval development of PLW varied between the different pulse crops with field peas and faba beans being the most susceptible and lentils and chickpeas being the least susceptible. Host plant resistance against PLW could provide more sustainable IPM approaches in the future. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Traits that mediate reproductive isolation between species, such as those involved in mate choice and/or recognition, are predicted to experience stabilizing selection towards the species mean. Male orchid bees collect chemical compounds from many sources, such as plants and fungi, which they use as a perfume signal (pheromone) during courtship display, and are suggested to contribute to reproductive isolation between species. Environmentally acquired signals are more prone to variation as source availability can vary through space and time. If orchid bee perfumes are important for reproductive isolation between species, we expect them to exhibit stable species-specific differences in time and space. Here, we describe phenotypic patterns of inter- and intraspecific variation in the male perfumes of three sympatric species of Euglossa orchid bees across an entire year, investigating both their seasonality and species specificity. Our analysis revealed considerable within-species variation in perfumes. However, species specificity was maintained consistently throughout the year, supporting the idea that these perfumes could play an important role in reproductive isolation and are experiencing stabilizing selection towards a species mean. Our analysis also identified strong correlations in the abundance of some compounds, possibly due to shared collection sources between species. Our study suggests that orchid bee perfumes are robust in the face of environmental changes in resource availability and thus can maintain reproductive isolation between species.

Abstract Background Populations of the plant pathogenic fungus Verticillium dahliae display a complex and rich genetic diversity, yet the existence of sexual reproduction in the fungus remains contested. As pivotal genes, MAT genes play a crucial role in regulating cell differentiation, morphological development, and mating of compatible cells. However, the functions of the two mating type genes in V. dahliae, VdMAT1-1-1, and VdMAT1-2-1, remain poorly understood. Results In this study, we confirmed that the MAT loci in V. dahliae are highly conserved, including both VdMAT1-1-1 and VdMAT1-2-1 which share high collinearity. The conserved core transcription factor encoded by the two MAT loci may facilitate the regulation of pheromone precursor and pheromone receptor genes by directly binding to their promoter regions. Additionally, peptide activity assays demonstrated that the signal peptide of the pheromone VdPpg1 possessed secretory activity, while VdPpg2, lacked a predicted signal peptide. Chemotactic growth assays revealed that V. dahliae senses and grows towards the pheromones FO-a and FO-α of Fusarium oxysporum, as well as towards VdPpg2 of V. dahliae, but not in response to VdPpg1. The findings herein also revealed that VdMAT1-1-1 and VdMAT1-2-1 regulate vegetative growth, carbon source utilization, and resistance to stressors in V. dahliae, while negatively regulating virulence. Conclusions These findings underscore the potential roles of VdMAT1-1-1 and VdMAT1-2-1 in sexual reproduction and confirm their involvement in various asexual processes of V. dahliae, offering novel insights into the functions of mating type genes in this species.

The main neuroendocrine pathways of induction of reproductive behavior in fish are elucidated. 17α, 20β-dihydroxy-4-pregnen-3-one (17,20β-DHP), an oocyte maturation-inducing hormone, was found to act as a pheromone to induce male reproductive behavior. 17α, 20β-DHP-sulfate (17,20β-DHP-S), a derivative of 17,20β-DHP, was also identified as a later-acting pheromone. In addition, prostaglandin F2 alpha (PGF2α), which is synthesized during female ovulation, has been shown to also act as a pheromone, inducing the final oviposition-inducing behavior to make fertilization successful. It appears that these molecular events are initiated by stimuli from the brain. Numerous neuropeptides have been discovered that promote the initiation of reproductive behavior. Recently, with the proliferation of genome editing technology, a detailed analysis of the molecules involved in these pathways is underway. Analysis of gene knockout in zebrafish and medaka is actively underway. On the other hand, many research reports have shown that the induction pathways of male reproductive behavior are adversely affected by chemical substances. Knowledge of the adverse effects of chemical substances is not only useful as information to prevent their mixing from the viewpoint of protecting the natural environment and as a point of caution in fish farming, but also provides clues for elucidating the pathways of reproductive behavior induction. The elucidation of the pathways of reproductive behavior induction is also important from the point of view of breeding technology for fish farming and biodiversity conservation. In this review, we summarize recent research on the pathways of male reproductive behavior induction in fish and the possibility of developing new aquaculture techniques depending on the results.

Field studies were conducted in the Sharya-Duhok / Kurdistan Region of Iraq to evaluate the influence of different light colors, three installation heights, and three types of traps on the capture of the tomato leaf miner moth. The light colors tested were yellow, white, green, blue and red. The trap installation heights were 70, 100, and 130 cm above ground level. The traps included a delta trap, a water trap and a new combined pheromone-equipped sticky light trap, referred to as the GLT trap. Results indicated that the white light was significantly more attractive to the tomato leaf miner, capturing 32% of the total moths, followed by the yellow, blue, green and red light with percentages (27, 22, 13, 6%), respectively. This significantly differed from traps installed at heights of 70 cm captured 70% of the total number caught, and it differed statistically from the traps installed at a height of 100 and 130 cm, which captured 19 and 11%, respectively, this suggests that moth flight activity is concentrated at the plant canopy level. The GLT trap demonstrated remarkable superiority over other trap types, capturing 52% of the total moths, significantly differing from the delta and water traps, which captured 37% and 11%, respectively. This suggests that exploiting the pest's behaviors, such as using the GLT trap, could be a promising approach to managing the pest in infested fields within a short period, complementing chemical control methods.

Variation in sex pheromones is regarded as one of the causes of reproductive isolation and speciation. We recently identified 51 male- and female-specific compounds – many of which function as sex pheromones – in 99 drosophilid species [1]. Here, we report that despite many of these compounds being shared between species, their quantities differ significantly. For example, although 34 drosophilid species share the male-specific compound cis-vaccenyl acetate (cVA), which plays a critical role in regulating various social and sexual behaviors, the amount of cVA can differ by up to 600-fold between different species. Additionally, we found 7-tricosene, the cuticular hydrocarbon pheromone, present in 35 Drosophila species. Our findings indicate that 7-tricosene is equally present in both sexes of 14 species, more abundant in males of 14 species, and more abundant in females of 7 species. We provide raw data on the concentration of potential pheromone components in the 99 drosophilids, which can provide important insights for further research on the behavior and evolution of these species. Quantitative variations highlight species-specific patterns, suggesting an additional mechanism for reproductive isolation built on specific combinations of compounds at set concentrations.

Over the past two decades, several headspace collection techniques have been used to detect and identify volatile organic compounds (VOCs) emitted by plants, pests, air, and soil. Volatiles emitted by pests and infected plants are usually found at low concentrations. The important challenge is to be able to capture an exact collection of relative quantities of the relevant VOCs. Herewe present an innovative headspace collecting device (HSCD) for sampling VOCs, which ensures an exact regulation of mass flow velocity and collected total gas volume allowing besides qualitative analysis of collected VOCs, an exact comparison of their relative quantities in plant or insect headspace samples. The HSCD possess six parallel odor collection systems each consisting of a digital mass flow detector and controller connected to a vacuum pump, which are mounted in a trolley suitcase, connected by tubes, and wired electrically. The programming of the channels, can be done by a digital control unit. Using the HSCD, VOCs emitted by the brown marmorated stink bug (BMSB), Halyomorpha halys, from its different developmental stages including egg, nymphal stages, nymphal exuvia, and adults were collected on thermal desorption tubes and analyzed using an automated thermal desorber connected to a gas chromatography-mass spectrometry system. Forty-five VOCs were identified in total, whichmainly consisted of tridecane (4.36- 69.33%), E-2-decenal (4.24-26.48%), 2-undecenal (0.63-50.03%), and E-4-oxo-2-hexenal (1.22-20.58%). The random forest analysis revealed three different chemical patterns among BMSB life stages samples. In conclusion, these results indicate that the new developed HSCD, a mobile, easy to use, and reliable instrument, has a high potential to sample relevant VOCs of a specific life stage of an insect both qualitatively and quantitatively. It was demonstrated that this information can be used for identifying specific chemical signatures, which fit to specific life stages of the BMSB, and may be used as biomarker for on-site detection of this pest e.g. in shipping containers or agricultural areas. [ABSTRACT FROM AUTHOR]

Pheromones are specialized chemical messengers used for inter-individual communication within the same species, playing crucial roles in modulating behaviors and physiological states. The detection mechanisms of these signals at the peripheral organ and their transduction to the brain have been unclear. However, recent identification of pheromone molecules, their corresponding receptors, and advancements in neuroscientific technology have started to elucidate these processes. In mammals, the detection and interpretation of pheromone signals are primarily attributed to the vomeronasal system, which is a specialized olfactory apparatus predominantly dedicated to decoding socio-chemical cues. In this mini-review, we aim to delineate the vomeronasal signal transduction pathway initiated by specific vomeronasal receptor-ligand interactions in mice. First, we catalog the previously identified pheromone ligands and their corresponding receptor pairs, providing a foundational understanding of the specificity inherent in pheromonal communication. Subsequently, we examine the neural circuits involved in processing each pheromone signal. We focus on the anatomical pathways, the sexually dimorphic and physiological state-dependent aspects of signal transduction, and the neural coding strategies underlying behavioral responses to pheromonal cues. These insights provide further critical questions regarding the development of innate circuit formation and plasticity within these circuits. [ABSTRACT FROM AUTHOR]

The main neuroendocrine pathways of induction of reproductive behavior in fish are elucidated. 17α, 20β-dihydroxy-4-pregnen-3-one (17,20β-DHP), an oocyte maturation-inducing hormone, was found to act as a pheromone to induce male reproductive behavior. 17α, 20β-DHP-sulfate (17,20β-DHP-S), a derivative of 17,20β-DHP, was also identified as a later-acting pheromone. In addition, prostaglandin F2 alpha (PGF2α), which is synthesized during female ovulation, has been shown to also act as a pheromone, inducing the final ovipositioninducing behavior to make fertilization successful. It appears that these molecular events are initiated by stimuli from the brain. Numerous neuropeptides have been discovered that promote the initiation of reproductive behavior. Recently, with the proliferation of genome editing technology, a detailed analysis of the molecules involved in these pathways is underway. Analysis of gene knockout in zebrafish and medaka is actively underway. On the other hand, many research reports have shown that the induction pathways of male reproductive behavior are adversely affected by chemical substances. Knowledge of the adverse effects of chemical substances is not only useful as information to prevent their mixing from the viewpoint of protecting the natural environment and as a point of caution in fish farming, but also provides clues for elucidating the pathways of reproductive behavior induction. The elucidation of the pathways of reproductive behavior induction is also important from the point of view of breeding technology for fish farming and biodiversity conservation. In this review, we summarize recent research on the pathways of male reproductive behavior induction in fish and the possibility of developing new aquaculture techniques depending on the results. [ABSTRACT FROM AUTHOR]

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Brown algal male gametes show chemotaxis to the sex pheromone that is released from female gametes. The chemotactic behavior of the male gametes is controlled by the changes in the beating of two flagella known as the anterior and posterior flagellum. Our previous study using Mutimo cylindricus showed that the sex pheromone induced an increment in both the deflection angle of the anterior flagellum and sustained unilateral bend of the posterior flagellum, but the mechanisms regulating these two flagellar waveforms were not fully revealed. In this study, we analyzed the changes in swimming path and flagellar waveforms with a high‐speed recording system under different calcium conditions. The extracellular Ca2+ concentration at 10−3 M caused an increment in the deflection angle of the anterior flagellum only when ionomycin was absent. No sustained unilateral bend of the posterior flagellum was induced either in the absence or presence of ionomycin in extracellular Ca2+ concentrations below 10−2 M. Real‐time Ca2+ imaging revealed that there is a spot near the basal part of anterior flagellum showing higher Ca2+ than in the other parts of the cell. The intensity of the spot slightly decreased when male gametes were treated with the sex pheromone. These results suggest that Ca2+‐dependent changes in the anterior and posterior flagellum are regulated by distinct mechanisms and that the increase in the anterior flagellar deflection angle and sustained unilateral bend of the posterior flagellum may not be primarily induced by the Ca2+ concentration. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examined the behavior of red palm weevils in the United Arab Emirates to develop better and more environmentally friendly trapping methods. The study was conducted in three phases from June to December 2023 in Ras Al Khaimah and Abu Dhabi. Chemical attractants, such as pheromones, ethyl acetate, and food baits, like dates and coconut water, were tested. The weevils were most active between 3:00 and 6:00 a.m., with 85.72% being captured during this period. Adding pheromones to the food bait increased the capture rate by 6.95 times, and while adding food bait and ethyl acetate, and pheromones improved the capture rate by 3.14 times compared to using pheromones alone. The newly synthesized pheromone captured 2.69 times more weevils than the commercially available pheromone. This study examined red palm weevil ecology in the United Arab Emirates to develop effective food baits, pheromone, and eco-friendly trapping methods. Three phases of investigation were conducted (from June to December 2023) on date palm farms in Ras Al Khaimah and Abu Dhabi. The first two phases, each 15 days long, were conducted in Ras Al Khaimah, whereas the third phase, 18 days long, was conducted in Abu Dhabi. Chemical attractants, such as existing pheromones and ethyl acetate, a newly synthesized ferruginol pheromone, and food baits, such as original dates, date paste, coconut water, and date palm syrup, were used to attract the weevils. Multi-funnel traps containing various attractant mixes were tested. The main activity of the red palm weevils was observed from 3:00 to 6:00 a.m., with 85.72 ± 3.39% being captured during this period, coinciding with cooler temperatures. When pheromones were added to the food bait, the capture rate increased by 6.95 ± 1.81 times. Combining food bait, ethyl acetate, and pheromones improved the capture rates by 3.14 ± 0.69 times compared to pheromones alone. The newly synthesized pheromone achieved capture rates 2.69 ± 0.07 times higher than those of the commercially available pheromone, confirming its suitability as a red palm weevil attractant. [ABSTRACT FROM AUTHOR]

The 19 species of Dendroctonus bark beetles native to North America include several of the most significant biotic mortality agents of conifers in this region, and they have impacted millions of hectares of forest in recent decades. Semiochemical attractants play several vital roles in the biology of these insects including host finding, host assessment, and mate finding. They are key to the virulence of these insects, since they mediate the mass attacks that enable killing and reproduction within healthy trees. These attractants consist of combinations of thirteen identified pheromone components in three primary chemical classes and at least ten host-associated compounds dominated by monoterpene hydrocarbons in host defensive resin. Due to their potential for use in pest management technologies, semiochemical attractants for Dendroctonus have received extensive research into their chemical compositions and effects on insect behavior. This paper is intended as a synthesis of this research over the past 60 years as well as a critical examination of approaches to investigation of this topic and interpretation of experimental results. Its purpose is to assist practitioners in formulating suitable attractive lures for use in applications and identify gaps in knowledge of the semiochemistry of Dendroctonus that should be addressed if the practical potential of attractants is to be fully realized. [ABSTRACT FROM AUTHOR]

Chemical senses, including olfaction, pheromones, and taste, are crucial for the survival of most animals. There has long been a debate about whether different types of senses might influence each other. For instance, primates with a strong sense of vision are thought to have weakened olfactory abilities, although the oversimplified trade-off theory is now being questioned. It is uncertain whether such interactions between different chemical senses occur during evolution. To address this question, we examined four receptor gene families related to olfaction, pheromones, and taste: olfactory receptor (OR), vomeronasal receptor type 1 and type 2 (V1R and V2R), and bitter taste receptor (T2R) genes in Hystricomorpha, which is morphologically and ecologically the most diverse group of rodents. We also sequenced and assembled the genome of the grasscutter, Thryonomys swinderianus. By examining 16 available genome assemblies alongside the grasscutter genome, we identified orthologous gene groups among hystricomorph rodents for these gene families to separate the gene gain and loss events in each phylogenetic branch of the Hystricomorpha evolutionary tree. Our analysis revealed that the expansion or contraction of the four gene families occurred synchronously, indicating that when one chemical sense develops or deteriorates, the others follow suit. The results also showed that V1R/V2R genes underwent the fastest evolution, followed by OR genes, and T2R genes were the most evolutionarily stable. This variation likely reflects the difference in ligands of V1R/V2Rs, ORs, and T2Rs: species-specific pheromones, environment-based scents, and toxic substances common to many animals, respectively. [ABSTRACT FROM AUTHOR]

Simple Summary: Climate change potentially threatens biodiversity, and in a changing environment, it is vitally important that we learn to understand how animals react to the predicted changes. In marine organisms, the sense of smell governs almost all essential behaviours animals exhibit, from finding food and detecting a predator to finding a mating partner. Interpreting animal behaviour when exposed to odour is a complex task, as many factors from seasonality to individuality, fitness, social status, and even weather and water chemistry influence an individual's response. Here, we examine the impacts of reducing seawater pH levels predicted for the end of the century upon decision-making in male shore crabs when exposed to the female reproductive odour, the female sex pheromone. There is a significant alteration in the responsiveness of male crabs, with large, more sexually active males taking significantly less time to detect and react to females but then showing less sexual mating activity once reaching the female odour. This disruption of olfactory communication can potentially impact the mating and reproductive success of this globally distributed species, showing that even coastal crustaceans that are known to be hardy and able to survive substantial stressors are potentially at risk from altered seawater chemistry associated with climate change. The effects of climate change are becoming more apparent, predominantly concerning the impacts of ocean acidification on calcifying species. Many marine organisms rely on chemical signals for processes such as foraging for food, predator avoidance, or locating mates. The process of how chemical cues in marine invertebrates function, and how this sensory mode is affected by pH levels, is less researched. We tested the impact of reduced pH (7.6), simulating end-of-the-century predicted average ocean pH, against current oceanic pH conditions (8.2), on the behavioural response of male shore crabs Carcinus maenas to the female sex pheromone bouquet consisting of Uridine–diphosphate (UDP) and Uridine–triphosphate (UTP). While in current pH conditions (8.2), there was a significant increase in sexual interactions in the presence of female pheromone, males showed reduced sexual behaviours at pH 7.6. The crab weight–pH relationship, in which larger individuals respond more intensely sexually in normal pH (8.2), is reversed for both the initial detection and time to locate the cue. These results indicate that lowered pH alters chemical signalling in C. maenas also outside the peak reproductive season, which may need to be taken into account when considering the future management of this globally invasive species. [ABSTRACT FROM AUTHOR]

Pheromone-binding proteins (PBPs) are specific odorant-binding proteins that can specifically recognize insect pheromones. Through transcriptional analysis of the antennae of adult Endoclita signifer, EsigPBP3 was discovered and identified, and EsigPBP3 was found to be highly expressed in the antennae of male moths. Based on the binding characteristics and ability of EsigPBP3, we can find the key ligands and binding site to consider as a target to control the key wood bore E. signifier. In this study, the fluorescence competitive binding assays (FCBA) showed that EsigPBP3 had a high binding affinity for seven key eucalyptus volatiles. Molecular docking analysis revealed that EsigPBP3 had the strongest binding affinity for the sexual pheromone component, (3E,7E)-4,7,11-trimethyl-1,3,7,10-dodecatetraene. Furthermore, same as the result of FCBA, the EsigPBP3 exhibited high binding affinities to key eucalyptus volatiles, eucalyptol, α-terpinene, (E)-beta-ocimene, (−)-β-pinene, and (−)-α-pinene, and PHE35, MET7, VAL10, PHE38, ILE52, and PHE118 are key sites. In summary, EsigPBP3 exhibits high binding affinity to male pheromones and key volatile compounds and the crucial binding sites PHE35, MET7, VAL10, PHE38, ILE52, and PHE118 can act as targets in the recognition of E. signifier pheromones. [ABSTRACT FROM AUTHOR]

Ant species exhibit behavioural commonalities when solving navigational challenges for successful orientation and to reach goal locations. These behaviours rely on a shared toolbox of navigational strategies that guide individuals under an array of motivational contexts. The mechanisms that support these behaviours, however, are tuned to each species' habitat and ecology with some exhibiting unique navigational behaviours. This leads to clear differences in how ant navigators rely on this shared toolbox to reach goals. Species with hybrid foraging structures, which navigate partially upon a pheromone-marked column, express distinct differences in their toolbox, compared to solitary foragers. Here, we explore the navigational abilities of the Western Thatching ant (Formicaobscuripes), a hybrid foraging species whose navigational mechanisms have not been studied. We characterise their reliance on both the visual panorama and a path integrator for orientation, with the pheromone's presence acting as a non-directional reassurance cue, promoting continued orientation based on other strategies. This species also displays backtracking behaviour, which occurs with a combination of unfamiliar terrestrial cues and the absence of the pheromone, thus operating based upon a combination of the individual mechanisms observed in solitarily and socially foraging species. We also characterise a new form of goalless orientation in these ants, an initial retreating behaviour that is modulated by the forager's path integration system. The behaviour directs disturbed inbound foragers back along their outbound path for a short distance before recovering and reorienting back to the nest. [ABSTRACT FROM AUTHOR]

BACKGROUND: Brown marmorated stink bug (BMSB), Halyomorpha halys (Stål), is an invasive and severe pest of specialty and row crops. A 2‐year field study conducted in four Mid‐Atlantic states in the USA characterized the spatial and temporal dynamics of BMSB populations and its association with landscape elements in commercial agriculture settings. In each state, two 1 km2 sites included typical landscape elements (i.e., tree fruit orchards, annual field and vegetable crops, woodlands, and human‐made structures). Twenty‐seven georeferenced pheromone traps were deployed per site and the number of BMSB adults and nymphs captured was counted throughout the growing season. RESULTS: Findings from spatial analysis by distance indices, along with time‐series maps of BMSB distribution, showed that BMSB exhibited significant spatial aggregation, and that its distribution was spatially consistent between years. Analyses with geographic information systems (GIS) revealed that BMSB 'hot spots' occurred in different landscape elements throughout each season. Most patches (i.e., clusters of significantly higher trap captures) were found near woodlands early in the season, near tree fruit orchards in summer, and on the border of annual field crops in autumn. Buffer analysis with GIS indicated that more BMSB adults were captured closer to woodlands compared with other landscape elements. CONCLUSION: Understanding the spatial and temporal movement and distribution of BMSB is critical to predicting their potential impact and ultimately devising strategies to mitigate this risk to vulnerable crops. The results of this study can be used to design streamlined, spatially‐based areawide management of BMSB in heterogeneous and complex agricultural landscapes. © 2023 Society of Chemical Industry. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Pheromones play a pivotal role in coordinating collective activities. Recent research has demonstrated that workers of the Japanese subterranean termite, Reticulitermes speratus, secrete an aggregation pheromone that induces quick assemble and prolonged stay at the pheromone source for nestmate workers, facilitating efficient dead-wood digestion and colony expansion. The question remains: do other termite species also utilize aggregation pheromones? In this study, we report that workers of the Formosan subterranean termite, Coptotermes formosanus, use a mixture of fatty acids as part of the pheromone components to maintain worker aggregation for extended periods of time. Through bioassays and gas-chromatography mass-spectrometry (GC–MS) analysis, we determined that a mixture of four fatty acids including palmitoleic acid, palmitic acid, (Z)-10-heptadecenoic acid, and stearic acid possesses arrestant activity but little or no attractant activity. Also, the inclusion of cholesterol and cuticular hydrocarbons reinforces only its arrestant activity. Further, GC–MS analysis of extracts of wood and soil, which serve as termite food, indicated that the pheromone components other than palmitic acid are not derived from their food, and GC analysis of extracts from different parts of the worker's body revealed that these components were most likely produced in the midgut and excreted to the outside of the body via the hindgut. These findings suggest that the aggregation pheromone components and their functions in C. formosanus are largely different from those in R. speratus. This research provides insights into the differences among termite species in the development of chemical signals triggering aggregation behavior. [ABSTRACT FROM AUTHOR]

The surging market demand for sea cucumbers (Apostichopus japonicus) has fueled a thriving growth in the sea cucumber breeding industry. Pheromones are molecules that evolve signals in defined proportions in the case of multicomponent pheromones, emitted by one individual and received by a second individual of the same species to cause a specific response. It remains an enigma as to how the species of sea cucumber, devoid of visual, auditory, and olfactory senses, aggregate and communicate within their groups, as well as coordinate gamete release during the breeding period. We hypothesize that pheromones may serve as the medium for facilitating these behaviors and propose conducting experiments centered around pheromonal investigation. In this study, we aimed to analyze common metabolites of male A. japonicus using LC-MS/MS technology and bioinformatics. Coelomic fluid and ejaculate fluid were analyzed, with aquaculture water serving as the control. Eight target pheromones were analyzed, and eight of metabolite analogs were tested for aggregation and spawning behaviors. Results showed that β-sitosterol at a concentration of 10 μg·L−1 significantly promoted aggregation (21.25 % average rate) and induced a significant increase in spawning rate (58 %) of A. japonicus. The significance of this study lies in the fact that by collecting and utilizing pheromones of A. japonicus, farmers can accurately determine the reproductive cycle and optimal breeding season for A. japonicus. This enables fish farmers to implement effective breeding management strategies at the appropriate time, thereby increasing the success rate of reproduction and providing valuable technical support for the cultivation of A. japonicus seedlings.

Faced with complex and ever-changing environmental conditions in the agricultural field, efficient agricultural information gathering is crucial for optimising agricultural output. Therefore, a new path planning algorithm combining ant colony algorithm and particle swarm optimization is proposed in this study. The aim is to achieve fast and accurate path planning for agricultural information gathering robots in diverse agricultural environments. The global search ability of particle swarm optimization algorithm in finding optimal paths and the local search advantage of ant colony algorithm in obstacle avoidance are used to optimise the movement strategy of robots in agricultural environments. The research results showed that the global path planning distance of this method was 19.328m. The execution time was 0.97s. In local path planning, the proposed algorithm had a fitness function value of 30.123 when the number of iterations reached 53. In mixed path planning, the proposed algorithm reduced the movement time by 3.2s. The conclusion shows that the algorithm proposed in this study has high applicability and efficiency in practical applications, providing an effective strategy for path planning of agricultural information gathering robots. It has important practical significance for promoting the development of intelligent agriculture.

The citrus long-horned beetle, Anoplophora chinensis (Coleoptera: Cerambycidae), is a highly polyphagous species native to eastern and southeastern Asia. Detection of these beetles is dependent on visual surveys, which are inefficient and labor-intensive. The identification and development of pheromone-based lures would help improve survey efforts for A. chinensis should it become established within the US. We identified three antennally active male-produced chemical components (nonanal, 4-(n-heptyloxy)butan-1-ol, and 4-(n-heptyloxy)butanal), which were then tested for behavioral activity at our USDA Quarantine laboratory. When tested together in Y-tube behavioral assays, a three-component blend of the identified compounds was shown to be attractive to adult female A. chinensis. Pheromone production and behavior of A. chinensis and other closely related Anoplophora cerambycid species are discussed in relation to mate finding and potential monitoring.

With the rise of Internet of Things (IoT) technology, fog computing has emerged as a promising solution for low-latency and real-time applications. As a highly virtualized platform, fog computing provides computing and storage services at the network edge to meet users' needs for latency-sensitive applications. However, resource scheduling is crucial in meeting customer demands and improving service quality. If the resource scheduling problem for large-scale service requests cannot be effectively solved, it will reduce resource utilization and decrease user satisfaction. Therefore, we propose a resource scheduling model called Normalization Processing to find the optimal pheromone for achieving the lowest total cost. The optimal resource scheduling result can be achieved by changing the ant pheromone concentration in the simulated foraging process. We also propose a resource scheduling algorithm called New Genetic Ant Colony Optimization (NGACO) Algorithm that a combination of the improved genetic algorithm (GA) and the improved ant colony optimization (ACO) algorithm. The GA is improved by incorporating a randomized initialization strategy, while the ACO algorithm is enhanced with the use of niche technology. NGACO algorithm introduces a pheromone update method optimization of three operators and a pheromone correction factor in the pheromone update rule. It can update pheromone generation by roulette algorithm. The NGACO algorithm effectively improves the exploratory power of the algorithm while ensuring initial population diversity. Additionally, we introduce a penalty mechanism to handle constraints, while the niche technology addresses the optimization problem of multimodal functions. The experimental results show that the NGACO algorithm demonstrates excellent resource scheduling performance, with a 14.7%, 25%, and 12.8% reduction in makespan, economic cost, and total cost, respectively, compared to the ACO algorithm. Furthermore, the load balancing is 34.7% higher than the ACO algorithm. [ABSTRACT FROM AUTHOR]

In the silkmoth Bombyx mori, the role of male sensilla trichodea in pheromone detection is well established. Here we study the corresponding female sensilla, which contain two olfactory sensory neurons (OSNs) and come in two lengths, each representing a single physiological type. Only OSNs in medium trichoids respond to the scent of mulberry, the silkworm's exclusive host plant, and are more sensitive in mated females, suggesting a role in oviposition. In long trichoids, one OSN is tuned to (+)-linalool and the other to benzaldehyde and isovaleric acid, both odours emitted by silkworm faeces. While the significance of (+)-linalool detection remains unclear, isovaleric acid repels mated females and may therefore play a role in avoiding crowded oviposition sites. When we examined the underlying molecular components of neurons in female trichoids, we found non-canonical co-expression of Ir8a, the co-receptor for acid responses, and ORco, the co-receptor of odorant receptors, in long trichoids, and the unexpected expression of a specific odorant receptor in both trichoid sensillum types. In addition to elucidating the function of female trichoids, our results suggest that some accepted organizational principles of the insect olfactory system may not apply to the predominant sensilla on the antenna of female B. mori. [ABSTRACT FROM AUTHOR]

Simple Summary: Sixteen cats were used in a model of behavioral and physiological transport stress. Cats were not accustomed to being transported. In an objective evaluation, cats wore a PetPace (PP) collar that recorded carotid pulse rate (PR) and general activity. Video cameras recorded cat behavior during the 70 min transport experience. Cats also wore a plastic collar containing either 2-methyl-2-butenal (2M2B) collars or a placebo collar. This randomized, placebo-controlled, blinded study found that cats with a 2M2B collar had a lower PR, slept more, sat less, and self-groomed more compared with cats wearing a placebo collar. Control cats hid near the back of the transport kennel, and some vomited or had excessive salivation, whereas cats with 2M2B collars did not hide, vomit, or salivate. This controlled study demonstrates behavioral and physiological benefits to transported cats from the use of 2M2B collars. Some cats experience stress when they have novel experiences, such as infrequent transport. This study was a randomized, placebo-controlled, blinded study that sought to objectively evaluate the effects of a 2M2B collar on transported cat physiology and behavior. The statistical model included effects of cat treatment (2M2B vs. control), period (70 min), sex, and interactions. Cats wearing 2M2B collars had an 8% lower PR (p < 0.01), and they slept more and did not hide at the back of the kennel. While control cats vomited or showed excess salivation, cats with 2M2B collars did not show these signs of stress. Male cats were less active during transport than females. Male cats slept more with 2M2B collars compared with male cats with a control collar, but females showed similar sleeping overall regardless of which collar they wore. Female cats increased activity during transport when they had a 2M2B collar, while male activity did not differ with control or 2M2B collars. These data support the concept that the semiochemical 2M2B can reduce stress in transported cats based on objective physiological and behavioral measures. [ABSTRACT FROM AUTHOR]

Aggregation pheromone (ferrolure+) has the potential for sueeessful deteetion, monitoring and management of Red palm weevil (RPW), Rhynchophorusferrugenius. Therefore, studies were undertaken to evaluate the effeetiveness of aggregation pheromone (ferrolure+) along with synthetie inseetieides i.e., Karate 0.25 EC (Lambda-eyhlothrin), Coragen 20SC (Chlorantranliprole), Curaeron 50 EC (profenophos), Steward 150EC (indoxaearb) andTalstar 10EC (bifenthrin) for the management of RPW. Control treatments with and without ferrolure+ were also maintained. Four traps per aere were applied in eaeh study arranged in a randomized eomplete bloek design. Weekly observations were taken till the effeetiveness of ferrolure+. Results eonfirmed that addition of synthetie inseetieides showed a negative impaet on the mean eapture of RPW exeept for indoxaearb (7.59±0.89 weevils per trap) that attraet signifieantly same but eomparatively less RPW attraeted towards only ferrolure+ pheromone traps (8.74±0.96 weevils per trap). Overall RPW eaptured in remaining treatments i.e., ehlorantranliprole, lambda-eyhlothrin, profenophos and bifenthrin were 4.56+0.65 weevils per trap; (5.22+0.69) weevils per trap; 5.63+0.71 weevils per trap and 5.48+0.89 weevils per trap, respeetively. A gradual rise was reeorded in mean eapture of RPW in all treatments till week five after installation and then deelined rapidly upto week eight. More than double number of females were eaptured in traps with maximum male to female ratio (1:2.26) eaptured in lambda-eyhlothrin treatment. Therefore, it is suggested that ferrolure+ traps should be ineluded in the integrated management programs of RPW and indoxaearb pestieide, if required, may be added in trap to get maximum killing of weevils, partieularly females that will also help reduee future population growth. [ABSTRACT FROM AUTHOR]

Field studies were conducted in the Sharya-Duhok / Kurdistan Region of Iraq to evaluate the influence of different light colors, three installation heights, and three types of traps on the capture of the tomato leaf miner moth. The light colors tested were yellow, white, green, blue and red. The trap installation heights were 70, 100, and 130 cm above ground level. The traps included a delta trap, a water trap and a new combined pheromone-equipped sticky light trap, referred to as the GLT trap. Results indicated that the white light was significantly more attractive to the tomato leaf miner, capturing 32% of the total moths, followed by the yellow, blue, green and red light with percentages (27, 22, 13, 6%), respectively. This significantly differed from traps installed at heights of 70 cm captured 70% of the total number caught, and it differed statistically from the traps installed at a height of 100 and 130 cm, which captured 19 and 11%, respectively, this suggests that moth flight activity is concentrated at the plant canopy level. The GLT trap demonstrated remarkable superiority over other trap types, capturing 52% of the total moths, significantly differing from the delta and water traps, which captured 37% and 11%, respectively. This suggests that exploiting the pest's behaviors, such as using the GLT trap, could be a promising approach to managing the pest in infested fields within a short period, complementing chemical control methods. [ABSTRACT FROM AUTHOR]

Simple Summary: All commercial swine farms require replacement gilts. Gilts are grown in pens and are commonly exposed to boars to induce estrus. Boar exposure to peri-puberal gilts is time-consuming, with variable results on commercial farms. Our goal was to determine whether a novel boar pheromone (Boar Better®; BB) could replace a live boar, accelerate the onset of puberty, and obtain equal or better percentages of gilts bred. A novel sprayer that allowed gilts to self-administer BB (a putative boar priming pheromone for gilts) at will. The sprayer is an environmental enrichment (EE) device that pigs root, push, and chew. The EE device can all gilts to self-deliver BB during the late pre-puberal period, which may save labor and improve worker and gilt safety by reducing the use of a live boar. In this work, gilts were exposed to either boars on a daily basis or BB self-administered in the EE sprayer. In conclusion, BB induced the same or more gilts to be identified in estrus compared to live boar exposure, and injured fewer gilts while reducing the labor and boar maintenance costs. The data support the idea that BB acted as a priming pheromone to stimulate the onset of estrus in gilts without a boar. Labor is in short supply in animal agriculture. One time-consuming task is estrus detection in gilts. Stimulation with a live boar causes the onset of puberty in young gilts. Typically, a live boar is used to stimulate and identify estrus in the gilts by exposing the gilts to him. Recently, a boar pheromone (BB) was developed to replace the use of a live boar for sows. Additionally, a novel automatic sprayer used as environmental enrichment (EE) by gilts for the self-administration of BB has been developed by this laboratory. A commercial study was conducted to determine whether the use of a live boar could be replaced with a simple EE sprayer, allowing gilts to self-administer BB. Our objective was to determine whether the number and percentage of gilts in estrus obtained using live boars was comparable to self-administration using an EE sprayer containing BB. A total of 242 gilts were randomly assigned to either a live boar (BOAR) or BB self-administration using the environmental enrichment (EE) sprayer. Gilts began simultaneous exposure to either the BOAR or the BB when they were about 4–5 months of age and this continued until they were found in estrus or were injured, died, or never cycled about 2 months later. A total of 83.3% of gilts with exposure to BOAR were identified in estrus and bred, while exposure to BB resulted in 92.9% of gilts reaching puberty and being bred (p < 0.05). The days to reach estrus were 11 days longer for gilts exposed to BB than BOAR. Eight percent more gilts were injured by the BOAR than by using BB (and no boar). The use of BB as a priming pheromone could prevent gilt injuries, save labor, and reduce costs for pig farmers while not inhibiting reproductive output. [ABSTRACT FROM AUTHOR]

Brassica vegetable and oilseed crops are attacked by several different flea beetle species (Chrysomelidae: Alticini). Over the past decades, most research has focused on two Phyllotreta species, Phyllotreta striolata and Phyllotreta cruciferae, which are major pests of oilseed rape in North America. More recently, and especially after the ban of neonicotinoids in the European Union, the cabbage stem flea beetle, Psylliodes chrysocephala, has become greatly important and is now considered to be the major pest of winter oilseed rape in Europe. The major challenges to flea beetle control are the prediction of population dynamics in the field, differential susceptibility to insecticides, and the lack of resistant plant cultivars and other economically viable alternative management strategies. At the same time, many fundamental aspects of flea beetle biology and ecology, which may be relevant for the development of sustainable control strategies, are not well understood. This review focuses on the interactions between flea beetles and plants and summarizes the literature on current management strategies with an emphasis on the potential for biological control in flea beetle management. [ABSTRACT FROM AUTHOR]

Vomeronasal sensory neurons (VSNs) recognize pheromonal and kairomonal semiochemicals in the lumen of the vomeronasal organ. VSNs send their axons along the vomeronasal nerve (VN) into multiple glomeruli of the accessory olfactory bulb (AOB) and form glutamatergic synapses with apical dendrites of mitral cells, the projection neurons of the AOB. Juxtaglomerular interneurons release the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Besides ionotropic GABA receptors, the metabotropic GABAB receptor has been shown to modulate synaptic transmission in the main olfactory system. Here we show that GABAB receptors are expressed in the AOB and are primarily located at VN terminals. Electrical stimulation of the VN provokes calcium elevations in VSN nerve terminals, and activation of GABAB receptors by the agonist baclofen abolishes calcium influx in AOB slice preparations. Patch clamp recordings reveal that synaptic transmission from the VN to mitral cells can be completely suppressed by activation of GABAB receptors. A potent GABAB receptor antagonist, CGP 52432, reversed the baclofen-induced effects. These results indicate that modulation of VSNs via activation of GABAB receptors affects calcium influx and glutamate release at presynaptic terminals and likely balances synaptic transmission at the first synapse of the accessory olfactory system. [ABSTRACT FROM AUTHOR]

Recent findings have documented the importance of (Z)‐11‐octadecenyl acetate (cVA) in the melanogaster group as a sex pheromone that regulates several sexual and social behaviours. However, this pheromone is missing in Drosophila suzukii, thus posing the question of whether it could have been replaced by another compound similar to cVA. Olfactory responses of D. suzukii females and males to conspecific volatiles in laboratory and field trails suggest the existence of a pheromone. Females attracted more females and males than the control. In field trials, both sexes were successfully captured in traps baited with conspecifics. Females were attracted to conspecific females and males. Gas chromatography coupled with mass spectrometry of volatiles showed that both sexes released 18 compounds, including Z‐9‐tricosene, hexacosane and heneicosane. Our results suggest that these compounds may influence the behaviour of D. suzukii and can act as sex or aggregation pheromones. [ABSTRACT FROM AUTHOR]