Shedding light with harmonic radar: Unveiling the hidden impacts of streetlights on moth flight behavior.

One of the most dramatic changes occurring on our planet is the ever-increasing extensive use of artificial light at night, which drastically altered the environment to which nocturnal animals are adapted. Such light pollution has been identified as a driver in the dramatic insect decline of the past years. One nocturnal species group experiencing marked declines are moths, which play a key role in food webs and ecosystem services such as plant pollination. Moths can be easily monitored within the illuminated area of a streetlight, where they typically exhibit disoriented behavior. Yet, little is known about their behavior beyond the illuminated area. Harmonic radar tracking enabled us to close this knowledge gap. We found a significant change in flight behavior beyond the illuminated area of a streetlight. A detailed analysis of the recorded trajectories revealed a barrier effect of streetlights on lappet moths whenever the moon was not available as a natural celestial cue. Furthermore, streetlights increased the tortuosity of flights for both hawk moths and lappet moths. Surprisingly, we had to reject our fundamental hypothesis that most individuals would fly toward a streetlight. Instead, this was true for only 4% of the tested individuals, indicating that the impact of light pollution might be more severe than assumed to date. Our results provide experimental evidence for the fragmentation of landscapes by streetlights and demonstrate that light pollution affects movement patterns of moths beyond what was previously assumed, potentially affecting their reproductive success and hampering a vital ecosystem service.

Sustainable pest control inspired by prey-predator ultrasound interactions.

Nocturnal moths evolved ultrasound-triggered escape maneuvers for avoiding predatory bats emitting ultrasonic echolocation calls. Using ultrasound for pest control is not a novel concept, but the technique has not been systemized because of the moths' habituation to sounds and the narrow directionality of conventional ultrasound speakers. Here, we report the use of pulsed ultrasonic white noise, which contributes to achieving ecologically concordant plant protection. An ultrasonic pulse, which is temporal mimicry of the search-phase pulse in the echolocation calls of a sympatric bat, was identified using neuroethological screening of eared moth-repelling ultrasounds; these pulses elicit flight-stopping reactions in moths but have no or little auditory adaptation. Such repellent ultrasounds broadcast from the cylindrical omni-azimuth ultrasound emitters suppressed the intrusion of gravid females of pest moths into cultivation fields. Thus, egg numbers and plant damage by hatched larvae were drastically reduced, enabling farmers to substantially skip applications of chemical insecticides for controlling moth pests.

Genetics of flight in spongy moths (Lymantria dispar ssp.): functionally integrated profiling of a complex invasive trait.

BACKGROUND: Flight can drastically enhance dispersal capacity and is a key trait defining the potential of exotic insect species to spread and invade new habitats. The phytophagous European spongy moths (ESM, Lymantria dispar dispar) and Asian spongy moths (ASM; a multi-species group represented here by L. d. asiatica and L. d. japonica), are globally invasive species that vary in adult female flight capability-female ASM are typically flight capable, whereas female ESM are typically flightless. Genetic markers of flight capability would supply a powerful tool for flight profiling of these species at any intercepted life stage. To assess the functional complexity of spongy moth flight and to identify potential markers of flight capability, we used multiple genetic approaches aimed at capturing complementary signals of putative flight-relevant genetic divergence between ESM and ASM: reduced representation genome-wide association studies, whole genome sequence comparisons, and developmental transcriptomics. We then judged the candidacy of flight-associated genes through functional analyses aimed at addressing the proximate demands of flight and salient features of the ecological context of spongy moth flight evolution. RESULTS: Candidate gene sets were typically non-overlapping across different genetic approaches, with only nine gene annotations shared between any pair of approaches. We detected an array of flight-relevant functional themes across gene sets that collectively suggest divergence in flight capability between European and Asian spongy moth lineages has coincided with evolutionary differentiation in multiple aspects of flight development, execution, and surrounding life history. Overall, our results indicate that spongy moth flight evolution has shaped or been influenced by a large and functionally broad network of traits. CONCLUSIONS: Our study identified a suite of flight-associated genes in spongy moths suited to exploration of the genetic architecture and evolution of flight, or validation for flight profiling purposes. This work illustrates how complementary genetic approaches combined with phenotypically targeted functional analyses can help to characterize genetically complex traits.

Minimizing IP issues associated with gene constructs encoding the Bt toxin - a case study.

BACKGROUND: As part of a publicly funded initiative to develop genetically engineered Brassicas (cabbage, cauliflower, and canola) expressing Bacillus thuringiensis Crystal (Cry)-encoded insecticidal (Bt) toxin for Indian and Australian farmers, we designed several constructs that drive high-level expression of modified Cry1B and Cry1C genes (referred to as Cry1BM and Cry1CM; with M indicating modified). The two main motivations for modifying the DNA sequences of these genes were to minimise any licensing cost associated with the commercial cultivation of transgenic crop plants expressing CryM genes, and to remove or alter sequences that might adversely affect their activity in plants. RESULTS: To assess the insecticidal efficacy of the Cry1BM/Cry1CM genes, constructs were introduced into the model Brassica Arabidopsis thaliana in which Cry1BM/Cry1CM expression was directed from either single (S4/S7) or double (S4S4/S7S7) subterranean clover stunt virus (SCSV) promoters. The resulting transgenic plants displayed a high-level of Cry1BM/Cry1CM expression. Protein accumulation for Cry1CM ranged from 5.18 to 176.88 µg Cry1CM/g dry weight of leaves. Contrary to previous work on stunt promoters, we found no correlation between the use of either single or double stunt promoters and the expression levels of Cry1BM/Cry1CM genes, with a similar range of Cry1CM transcript abundance and protein content observed from both constructs. First instar Diamondback moth (Plutella xylostella) larvae fed on transgenic Arabidopsis leaves expressing the Cry1BM/Cry1CM genes showed 100% mortality, with a mean leaf damage score on a scale of zero to five of 0.125 for transgenic leaves and 4.2 for wild-type leaves. CONCLUSIONS: Our work indicates that the modified Cry1 genes are suitable for the development of insect resistant GM crops. Except for the PAT gene in the USA, our assessment of the intellectual property landscape of components presents within the constructs described here suggest that they can be used without the need for further licensing. This has the capacity to significantly reduce the cost of developing and using these Cry1M genes in GM crop plants in the future.

Moth resonant mechanics are tuned to wingbeat frequency and energetic demands.

An insect's wingbeat frequency is a critical determinant of its flight performance and varies by multiple orders of magnitude across Insecta. Despite potential energetic benefits for an insect that matches its wingbeat frequency to its resonant frequency, recent work has shown that moths may operate off their resonant peak. We hypothesized that across species, wingbeat frequency scales with resonance frequency to maintain favourable energetics, but with an offset in species that use frequency modulation as a means of flight control. The moth superfamily Bombycoidea is ideal for testing this hypothesis because their wingbeat frequencies vary across species by an order of magnitude, despite similar morphology and actuation. We used materials testing, high-speed videography and a model of resonant aerodynamics to determine how components of an insect's flight apparatus (stiffness, wing inertia, muscle strain and aerodynamics) vary with wingbeat frequency. We find that the resonant frequency of a moth correlates with wingbeat frequency, but resonance curve shape (described by the Weis-Fogh number) and peak location vary within the clade in a way that corresponds to frequency-dependent biomechanical demands. Our results demonstrate that a suite of adaptations in muscle, exoskeleton and wing drive variation in resonant mechanics, reflecting potential constraints on matching wingbeat and resonant frequencies.

Morph-linked variation in female pheromone signalling and male response in a polymorphic moth.

Understanding the maintenance of genetic variation in reproductive strategies and polymorphisms in the wild requires a comprehensive examination of the complex interactions between genetic basis, behaviour and environmental factors. We tested the association between three colour genotypes and variation in female pheromone signalling and male antennal morphology in the wood tiger moth (Arctia plantaginis). These moths have genetically determined white (WW, Wy) and yellow (yy) hindwings that are linked to mating success and fitness, with heterozygotes (Wy) having an advantage. We hypothesized that attractiveness and reproductive success are correlated, with Wy females being more attractive than the other two genotypes which could contribute to maintaining the polymorphism. Female attractiveness was tested by baiting traps with females of the three colour genotypes both in low- (i.e. field set-up) and in high-population density (i.e. large enclosure set-up). Male's ability to reach females was correlated to their own colour genotype and antennal morphology (length, area and lamellae count). Contrary to our prediction, morph-related reproductive success and attractiveness were not correlated. Heavier Wy females attracted a lower proportion of males compared to WW and yy females. Specifically, an increase in weight corresponded to a decreased Wy but increased yy female attractiveness. yy females were generally more attractive than others likely due to earlier pheromone release. In males, lamellae count and genetic colour morph were linked to the male's ability to locate females. Furthermore, male traits affected their ability to reach females in a context-specific way. Males with denser antennae (i.e. higher lamellae count) and white males reached the females faster than yellows in the enclosure, while yellow males located females faster than whites in the field. Our results indicate that higher yy female attractiveness was likely affected by the combined effect of early pheromone release, female weight and higher population density. Males' searching success was affected by morph-specific behavioural strategies and local population density. Ultimately, the combined effect of genotype-related pheromone signalling strategies of females together with environment-dependent male behaviour affect male response and potentially contribute to maintaining variation in fitness-related traits.

Tiger beetles produce anti-bat ultrasound and are probable Batesian moth mimics.

Echolocating bats and their eared insect prey are in an acoustic evolutionary war. Moths produce anti-bat sounds that startle bat predators, signal noxiousness, mimic unpalatable models and jam bat sonar. Tiger beetles (Cicindelidae) also purportedly produce ultrasound in response to bat attacks. Here we tested 19 tiger beetle species from seven genera and showed that they produce anti-bat signals to playback of authentic bat echolocation. The dominant frequency of beetle sounds substantially overlaps the sonar calls of sympatric bats. As tiger beetles are known to produce defensive chemicals such as benzaldehyde and hydrogen cyanide, we hypothesized that tiger beetle sounds are acoustically advertising their unpalatability. We presented captive big brown bats (Eptesicus fuscus) with seven different tiger beetle species and found that 90 out of 94 beetles were completely consumed, indicating that these tiger beetle species are not aposematically signalling. Instead, we show that the primary temporal and spectral characteristics of beetle warning sounds overlap with sympatric unpalatable tiger moth (Arctinae) sounds and that tiger beetles are probably Batesian mimics of noxious moth models. We predict that many insect taxa produce anti-bat sounds and that the acoustic mimicry rings of the night sky are hyperdiverse.

Genetic diversity of diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae) populations in Türkiye.

BACKGROUND: Diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae), is an important worldwide pest of plants belonging to the Brassicaceae family. In this study, we investigated genetic diversity of DBM populations in Brassicaceae production areas in Türkiye using the partial mtDNA CO1 gene region. METHODS: We determined 43 samples from 11 different populations for haplotype variations using the partial mitochondrial DNA sequences a 684 bp fragment of the CO1 gene. RESULTS: The results indicated that, the average haplotype diversity (Hd) was determined as 0.962 and nucleotide diversity (π) was determined as 0.557%. In neutrality tests, negative values were obtained in Tajima's D and Fu' Fs tests (Fu' Fs=-0.40, Tajima's D=-0.01). Tajima's D test was not found significant (p > 0.05). Fst value among DBM population estimates ranged from 0 to 0.631. Barcode gap distance was determined as 1.6%, but the intraspecies of genetic distance were found to be 0.15%. CONCLUSION: In conclusion, the presented study provided detailed and fundamental information about the genetic diversity of DBM populations in Türkiye. Further studies are needed to develop alternative pest management strategies for DBM populations integrating genetic approaches.

Mating Disruption of a Flighted Spongy Moth, Lymantria Dispar Japonica (Motchulsky) in Japan.

Mating disruption of a flighted spongy moth, Lymantria dispar japonica (Motchulsky)(Lepidoptera: Lymantridae), with a synthetic version of its sex pheromone, (+)-disparlure ([7R,8S] -cis-7,8-epoxy-2- methyloctadecane), was tested in the forests in Japan. Pheromone trap catches and the percentage mating of tethered females were measured in the pheromone-treated and untreated control forests. The attraction of male moths to pheromone traps placed at a height of 1.5 m was significantly disrupted when the pheromone dispensers were placed at 1.5 m height, but many moths were captured in control plots. Mating of tethered females placed at 1.5 m was inhibited entirely, while 44% of females were mated in an untreated control forest. We report the first trial of mating disruption against a flighted spongy moth, and these results suggest that mating disruption with the synthetic sex pheromone appears promising for reducing damage caused by L. dispar japonica.

Effect of fluorescent brighteners on the insecticidal activity of Bacillus thuringiensis var. kurstaki and LdMNPV on Lymantria dispar asiatica in Korea.

Stilbene-based fluorescent brighteners (FBs) have been demonstrated to improve the insecticidal activities of entomopathogenic viruses; however, there is limited information regarding their effect on entomopathogenic bacteria. We conducted this study to investigate the effect of two FBs (FB 28 and FB 71) on the insecticidal activities of Bacillus thuringiensis var. kurstaki (Btk) and Lymantria dispar multiple nuclear polyhedrosis virus (LdMNPV) on Lymantria dispar asiatica. FB 28 and Btk combination at low concentration (1.6 × 102 IU/mL) increased the mortality, whereas FB 71 and Btk combination at intermediate and high concentrations (1.6 × 103 and 1.6 × 104 IU/mL) slightly reduced the mortality compared with that with Btk alone. The lethal time was also shorter with combinations of Btk and FB 28 than with FB 71. Both FB 28 and FB 71 increased the mortality in combination with LdMNPV at all concentrations (3 × 102 , 3 × 104 , and 3 × 106 polyhedral occlusion bodies/mL compared with that with LdMNPV alone. Our results suggest that FBs improve the insecticidal activities of Btk and LdMNPV, and their activities depend on their interactions with the midgut structures of the host insect species.

Comparative transcriptome analysis reveals disruption of Plutella xylostella immune system by fungal peptide cyclosporin C.

The diamondback moth (Plutella xylostella), a major threat to crucifers across the globe, has developed resistance against the majority of insecticides enhancing the need for alternate control measures against this pest. Recently cyclosporin C, a secondary metabolite produced by the insect pathogenic fungus Purpeocillium lilacinum, has been reported to induce lethal and sub-lethal effects against P. xylostella. To date, little is known about the molecular mechanisms of interaction between cyclosporin C and P. xylostella immune systems. This study reports the transcriptome-based immune response of P. xylostella to cyclosprin C treatment. Our results showed differential expression of 322, 97, and 504 differentially expressed genes (DEGS) in P. xylostella treated with cyclosporin C compared to control 24, 48, and 72 h post-treatment, respectively. Thirteen DEGs were commonly expressed at different time intervals in P. xylostella larvae treated with cyclosporin C compared to control. Cyclosporin C treatment induced the down-regulated expression of majority of immune-related genes related to pattern recognition responses, signal modulation, Toll and IMD pathways, antimicrobial peptides and antioxidant responses confirming the ability to suppress immune response of P. xylostella. These results will further improve our knowledge of the infection mechanism and complex biochemical processes involved in interaction between cyclosporin C and insect immune systems.

Microsporidia-cypovirus interactions during simultaneous infection of the tree defoliator Dendrolimus sibiricus (Lepidoptera: Lasiocampidae).

The Siberian moth, Dendrolimus sibiricus is a dangerous forest defoliator, the number one pest of boreal forests in Asia. Search for effective and ecologically friendly control measures drives attention to microbial pathogens. Viruses and microsporidia are obligate intracellular parasites widespread in insect populations causing either chronic or acute infections. Interactions of these pathogens vary from antagonistic to synergistic. The goal of the work was to test a recently discovered cytoplasmatic polyhedrosis virus (cypovirus) strain DsCPV-1 isolated from D.sibiricus, combined with a microsporidium, against D. sibiricus, by feeding the inoculum (viral polyhedral and microsporidian spores). Three different microsporidian parasites of lepidopterans were tested against D. sibiricus as monoinfection: Nosema bombycis from silkworm, N. pyrausta from corn borer, and Tubulinosema loxostegi from beet webworm. Nosema bombycis was the most virulent, with a median lethal time of 7 days in the first and second instars treated with 100,000 and 1 million spores/larva, respectively. Nosema bombycis (dose 100,000 spores/larva) was chosen to test it as mixed infection in combination with an extremely low dose of DsCPV-1 (1 polyhedron/larva) against two races of D. sibiricus second instar larvae (the fir-feeding race and the larch-feeding race). The mixed infection demonstrated the most prominent negative effect on larval lethal time and weight for the both tested races. Mixed infections showed a synergistic effect for the fir-feeding larvae but additive effect only for the larch feeding larvae. Both pathogens co-developed successfully in the larvae with equal ratio of producing inoculum. The combination of these entomopathogens is therefore promising for forest protection against the Siberian moth and could be the way to significantly decrease the amount of pathogens applied in field.

Analysis of insecticide resistance and de novo transcriptome assembly of resistance associated genes in the European grapevine moth, Lobesia botrana (Lepidoptera: Tortricidae).

The European grapevine moth Lobesia botrana (Denis & Shiffermüller 1776) is an economically important pest of the vine-growing areas worldwide. Chemical insecticides have been used for its control; however, its resistance status is largely unknown in many regions. We monitored the susceptibility of several L. botrana populations from Greece and Turkey. In addition, based on RNAseq transcriptome analysis, we identified and phylogenetically classify the cytochrome P450 genes of L. botrana, as well as analysed target site sequences and looked for the presence of known resistance mutations. Resistance against chlorantraniliprole, alpha-cypermethrin, spinetoram, etofenprox, and acetamiprid was very low (below 2.5-fold in all cases, compared to a reference strain from Greece) in all populations from Greece that were included in the study. However, resistance against indoxacarb (4-30-fold), spinosad (5-59-fold), and deltamethrin (18-30 fold) was detected in the L. botrana populations from Turkey, compared to a reference population from Turkey. De novo transcriptome assembly and manual annotation, and subsequent PCR-based analysis of insecticide target sequences (i.e. voltage-gated sodium channel - VGSC: target of pyrethroids and oxadiazines; nicotinic acetylcholine receptor subunit a6 - nAChR_α6: target of spinosad; ryanodine receptor - RyR: target of diamides; glutamate-gated chloride channel - GluCl: target of avermectins and; acetylcholinesterase - AChE: target of organophosphates) showed the absence of known resistance mutations in all specimens from both countries. Finally, the L. botrana CYPome (116 genes) was manually analysed and phylogenetically characterised, to provide resources for future studies that will aim the analysis of metabolic resistance.

Lethal effect of Goniozus legneri on Cactoblastis cactorum: A potential biocontrol agent for inundative releases.

Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae), the cactus moth, is native to South America with a widespread distribution in Argentina. The larvae consume the interior of Opuntia spp. (Cactaceae) plants. The moth was used as a biocontrol agent against invasive non-native Opuntia spp. in many countries around the world. The cactus moth arrived unintentionally in Florida, USA, expanded its range and threatened Opuntia-based agriculture and natural ecosystems in southern North America. The insect is also a pest of cultivated O. ficus-indica L. in Argentina. An endemic South American parasitoid, Goniozus legneri Gordth (Hymenoptera: Bethylidae), is used in inundative biological control programmes against lepidopteran pests. The goal of this work was to evaluate G. legneri as a biocontrol agent to be used in inundative releases against C. cactorum. Mortality of C. cactorum by G. legneri was assessed at different spatial scales, as well as the interactions with Apanteles opuntiarum Martínez & Berta (Hymenoptera: Braconidae), a common Argentine natural enemy of C. cactorum. The ability of G. legneri to paralyse, parasitise and kill C. cactorum was confirmed. The paralysis inflicted on C. cactorum larvae reduced larval damage to the plants by 85%. Using two parasitoid species increased the mortality of C. cactorum larvae, but it was highly dependent on the order of their arrival. The combined mortality caused by both parasitoids was higher than a single one, in particular when G. legneri arrived first (56 ± 1%), suggesting asymmetric competition due to the preference of G. legneri attacking previously parasitised larvae. Goniozus legneri has potential as an inundative biocontrol agent of C. cactorum, but its interaction with the classical biocontrol agent A. opuntiarum needs to be considered.

The 'Goldilocks Grub': reproductive responses to leafroller host development in Goniozus jacintae, a parasitoid of the light brown apple moth.

Many parasitoids alter their reproductive behaviour in response to the quality of encountered hosts. They make adaptive decisions concerning whether to parasitise a potential host, the number of eggs laid on an accepted host, and the allocation of sex to their offspring. Here we present evidence that Goniozus jacintae Farrugia (Hymenoptera: Bethylidae), a gregarious ectoparasitoid of larval tortricids, adjusts its reproductive response to the size and developmental stage of larvae of the light brown apple moth (LBAM), Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae). Goniozus jacintae parasitises instars 3-6 of LBAM, but most readily parasitises the later, larger, instars. Brood sizes were bigger on larger hosts and brood sex ratios were female biased (proportion of males = 0.23) with extremely low variance (never >1 male in a brood at emergence), perhaps the most precise of all studied bethylids. Host size did not influence brood development time, which averaged 19.64 days, or the body size of male offspring. However, the size of females was positively correlated with host size and negatively correlated with brood size. The sizes of individual males and females were positively related to the average amount of host resource available to individuals within each brood, suggesting that adult body size is affected by scramble competition among feeding larvae. Average brood sizes were: 3rd instar host, 1.3 (SE ± 0.075); 4th instar, 2.8 (SE ± 0.18); 5th instar, 4.7 (SE ± 0.23); 6th instar, 5.4 (SE ± 0.28). The largest brood size observed was 8 individuals (7 females, 1 male) on the 6th instar of LBAM. These results suggest that later instars would give the highest yield to optimise mass-rearing of G. jacintae if used for augmentative biological pest control.

Functional characterization of sex pheromone receptors PflaOR29 and PflaOR44 involved in the chemoreception of a diurnal moth, Phauda flammans (Walker) (Lepidoptera: Phaudidae).

Recognition of sex pheromones released by heterosexual moths via sex pheromone receptors is key for establishing mating connections in moths. The day-flying moth Phauda flammans is an oligophagous pest in southern cities of China and Southeast Asian countries. Our previous study reported that male P. flammans can be attracted to two sex pheromone compounds [Z-9-hexadecenal and (Z, Z, Z)-9,12,15-octadecadienal] released by females in the field; however, the mechanism of olfactory recognition is not clear. In this study, two sex pheromone receptor genes (PflaOR29 and PflaOR44) were cloned. Among the different tissues, both PflaOR29 and PflaOR44 were highly expressed in the antennae of mated male adults. At different developmental stages, the expression levels of PflaOR29 and PflaOR44 were significantly greater in mated male adults than other stages. The fluorescence signals of PflaOR29 and PflaOR44 were mostly distributed on the dorsal side of the antennae, with a large number of trichoid sensilla. The results of the gene function of PflaOR29 and PflaOR44 based on a Drosophila empty neuron heterologous expression system indicated that PflaOR29 strongly responded to (Z, Z, Z)-9,12,15-octadecadienal but not to Z-9-hexadecenal, whereas PflaOR44 did not respond to the two sex pheromones. Our findings clarify the sex pheromone receptor gene corresponding to (Z, Z, Z)-9,12,15-octadecatrienal. These results provide essential information for analyzing the mechanism of sexual communication in diurnal moths and for identifying target genes for the development of efficient attractants.

Oviposition behavior of the quasi-gregarious parasitoid, Ooencyrtus kuvanae (Hymenoptera: Encyrtidae).

The parasitoid wasp, Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyrtidae), is a natural enemy of the spongy moth, a significant forest pest in North America. We investigated the oviposition behavior of O. kuvanae females on spongy moth egg masses by (i) presenting female parasitoids with a single spongy moth egg mass that was replaced every day, 2nd day, 4th day, 8th day, or 16th day (which is the total length of the oviposition period) and (ii) presenting female parasitoids with 1, 2, 4, or 8 egg masses at a time. Offspring developmental length ranged from 18 to 24 days. On average, male offspring exhibited faster developmental times, emerging approximately 1 day ahead of females. The amount of time that adult females spent on an egg mass affected the number of parasitized eggs. Specifically, more offspring emerged in the 4-, 8-, and 16-day treatments than in scenarios involving daily or every second-day egg mass replacement. The percentage of male offspring decreased as the number of egg masses presented to females increased. Interestingly, the total number of female offspring remained constant, but the number of male offspring decreased with an increase in the number of egg masses and time spent by the parent within a patch. The observed sexual dimorphism in development time, the influence of resource availability on offspring sex ratios, and flexible oviposition patterns illustrate the adaptability of O. kuvanae in response to varying conditions. These insights have implications for our understanding of parasitoid-host interactions and their potential role in biological control strategies.

Analysis of comb-gnawing behavior in Apis cerana cerana (Hymenoptera: Apidae).

Apis cerana cerana exhibits a prominent biological trait known as comb gnawing. In this study, gnawed combs from colonies during different seasons were collected, investigating the comb age and locations of gnawing. Patterns of comb gnawing were recorded, and the effects of 2 factors, namely, comb type and season, on the mass of wax residues and the gnawed surface area were measured. The results revealed that A. c. cerana predominantly gnaws combs that have been used for over 6 months, with gnawing concentrated in the brood-rearing area. In the first 3 seasons, significantly higher masses of wax residues and larger gnawed surface areas were found in greater wax moth larvae (GWML)-infested combs compared to newly built and old combs. Also, there were significantly higher masses and areas gnawed by A. c. cerana in old combs compared to newly built combs in all 4 seasons. Compared to other seasons, it exhibited significantly higher masses and areas resulting from comb-gnawing in newly built or old combs in winter. However, there were no significant differences in the masses of wax residues and surface areas gnawed in GWML-infested combs across the first 3 seasons. In conclusion, this study documented the impact of comb type and season on the comb-gnawing behavior of A. c. cerana, contributing to beekeeping management practices and the current understanding of bee biology.

Improved Immune Moth-Flame Optimization Based on Gene Correction for Automatic Reverse Parking.

During the process of reverse parking, it is difficult to achieve the ideal reference trajectory while avoiding collision. In this study, with the aim of establishing reference trajectory optimization for automatic reverse parking that smooths and shortens the trajectory length and ensures the berthing inclination angle is small enough, an improved immune moth-flame optimization method based on gene correction is proposed. Specifically, based on the standard automatic parking plane system, a reasonable high-quality reference trajectory optimization model for automatic parking is constructed by combining the cubic spline-fitting method and a boundary-crossing solution based on gene correction integrated into moth-flame optimization. To enhance the model's global optimization performance, nonlinear decline strategies, including crossover and variation probability and weight coefficient, and a high-quality solution-set maintenance mechanism based on fusion distance are also designed. Taking garage No.160 of the Dalian Shell Museum located in Dalian, Xinghai Square, as the experimental site, experiments on automatic parking reference trajectory optimization and tracking control were carried out. The results show that the proposed optimization algorithm provides higher accuracy for reference trajectory optimization and can achieve better tracking control of the reference trajectory.

Robotic Odor Source Localization via Vision and Olfaction Fusion Navigation Algorithm.

Robotic odor source localization (OSL) is a technology that enables mobile robots or autonomous vehicles to find an odor source in unknown environments. An effective navigation algorithm that guides the robot to approach the odor source is the key to successfully locating the odor source. While traditional OSL approaches primarily utilize an olfaction-only strategy, guiding robots to find the odor source by tracing emitted odor plumes, our work introduces a fusion navigation algorithm that combines both vision and olfaction-based techniques. This hybrid approach addresses challenges such as turbulent airflow, which disrupts olfaction sensing, and physical obstacles inside the search area, which may impede vision detection. In this work, we propose a hierarchical control mechanism that dynamically shifts the robot's search behavior among four strategies: crosswind maneuver, Obstacle-Avoid Navigation, Vision-Based Navigation, and Olfaction-Based Navigation. Our methodology includes a custom-trained deep-learning model for visual target detection and a moth-inspired algorithm for Olfaction-Based Navigation. To assess the effectiveness of our approach, we implemented the proposed algorithm on a mobile robot in a search environment with obstacles. Experimental results demonstrate that our Vision and Olfaction Fusion algorithm significantly outperforms vision-only and olfaction-only methods, reducing average search time by 54% and 30%, respectively.