Insect Movement Research Articles

Evaluation of aminoethoxyvinylglycine (AVG) for control of vector-borne diseases in solanaceous crops

Every year, solanaceous crops, such as potato (Solanum tuberosum) and tomato (Solanum lycopersicum), suffer important economic loss due to insect pests and the diseases they transmit. While pesticides can be used to control insects directly, they can exacerbate some vector-borne diseases by increasing insect movement among plants and thus increase disease transmission. The purpose of this study was to evaluate the use of aminoethoxyvinylglycine (AVG), an inhibitor of ethylene biosynthesis, as a potential control strategy for insect vectors and vector-borne disease of tomato and potato. AVG application (0.5 g/L) was evaluated in field plots and insect populations were monitored. Two field applications of AVG reduced total insect and leafhopper populations in tomato and potato plots, however, AVG increased thrips populations in tomato fields later in the growing season. Dual-choice bioassays were performed to examine the effect of AVG on insect preference toward virus-infected plants. AVG application reduced aphid preference to Potato leafroll virus infected potato plants but did not affect leafhopper preference to Beet curly top virus infected tomato plants. Taken together, these results suggest that AVG has the potential to be used as a component of integrated management practices, but additional studies will be required.

Nanoparticles as potential external markers for mark–release–recapture studies on Tribolium castaneum

AbstractStudies of insect movement are hampered by the small size of insects and the associated difficulty in tracking them in the environment. We tested the potential of quantum dots (QDs) to mark large numbers of insects very quickly. Our results demonstrate that green CdTe (cadmium tellurium) QDs were effective markers in the laboratory and can be applied to large numbers of insects very easily. Successful recaptures in the field demonstrate that QDs have great potential as external markers.

Lift and Drag Analysis of a Bionics Flapping Aircraft

This article focuses on the study of bionic wings. Based on the analysis of insect thoracic cavity structure and movement mechanism, two groups of insect flapping wings models were simulated, and unsteady aerodynamic problems were studied using computational fluid dynamics numerical simulation methods, with emphasis on computer simulation, iterative calculation equations and observation. The convergence is used to analyze the driving force curve, verify and analyze the influence of air fluid on the surface pressure and speed of the wing during the flight of the insect. Studying the influence of fluid mechanics during insect flight is of great significance to further optimize and improve existing aircraft structure forces.

Assessing repellency, movement, and mortality of three species of stored product insects after exposure to deltamethrin-incorporated long-lasting polyethylene netting

Long-lasting insecticide-treated netting (LLIN) has begun to be used in agricultural product protection. We investigated the effect of a deltamethrin-incorporated LLIN on three stored product insects, red flour beetle, Tribolium castaneum (Herbst), lesser grain borer, Rhyzopertha dominica (F.), and rice weevil, Sitophilus oryzae (L.). Long-distance repellency was assessed in a wind tunnel for adults of each species, but no repellency was observed. Insect movement and behavior was assessed by observing the movement of adult beetles on treated and untreated netting during a 5 min period for distance traveled, velocity, mobility, and time on each netting type. Among all netting combinations, T. castaneum spent the most time highly mobile, higher velocity, and traveled a greater distance. Sitophilus oryzae and R. dominica spent significantly more time immobile and lower velocity. Efficacy of LLIN was tested by exposing adults for 60 min, removing, and holding with or without food, and monitoring for mortality up to 7 d. All S. oryzae and R. dominica were either affected or dead at all post-exposure times. The number of affected and dead adult T. castaneum combined 7 d after exposure was 42% and 95%, with or without food, respectively, and 52% of affected adults were able to recover when food was present. Overall, LLIN had no repellency or negative effect on insect movement, which increases the probability of lethal exposures of adults from walking on the netting. LLIN can be adopted in existing integrated pest management (IPM) programs for food processing facilities to prevent stored product insect infestations.

Roles of roadside vegetation in insect conservation in Australia

AbstractThe extent and variety of roadside environments in Australia in largely anthropogenic landscapes render them substantial remnant habitats for insect biodiversity. The importance of these areas for insect biodiversity conservation and the key threats they face are discussed, as well as the needs for their protection and conservation management. Many rural roadsides harbour significant patches of native vegetation, including rare and threatened flora now scarce elsewhere. Other values of roadside vegetation include habitat remnants, seasonal refuges, corridors and shelters for insect movements and population connectivity. Examples are given of the importance of roadsides for individual threatened insect species. Roadside environments are under substantial threat from clearing, development and unintentional degradation through a variety of activities. The diverse responsibilities of roadside management, increasingly to harmonise human safety and amenity needs with biodiversity conservation, can readily incorporate considerations of insect diversity and occurrence of notable individual species. The conservation of remnant vegetation and ecological restoration of roadside corridors are highlighted as paramount for maintaining biodiversity and connectivity under increased human activity and environmental extremes.

Habitat use and movements of a large dragonfly (Odonata: Anax imperator) in a pond network

Abstract Local movements of aquatic insects within the surroundings of waterbodies aim essentially to find food, mates, resting sites, or avoid predation. Distances moved are very variable among species and may also differ depending on sex or age at the intraspecific scale. Despite a large panel of studies on odonate activities near waterbodies, little is known about their movements and behaviour in the surrounding landscape matrix. This knowledge is, however, crucial to support management schemes of pond networks and allow improvement of connectivity between them. In this study, 87 individuals of the large dragonfly Anax imperator were identified with a unique code on the wings and monitored visually on five ponds during summers 2017 and 2018. Simultaneously, 54 individuals were equipped with radio transmitters and tracked for up to 15 days. We built Cormack Jolly Seber models to test which factors are important for movement and survival of individuals, and calculated home ranges. Additionally, we performed a step selection analysis on the telemetry data to identify the terrestrial habitats selected by A. imperator at the interface between a rural area and a suburban area in north‐western France. A reduction of the survival rate was observed on the day immediately following capture regardless of the marking method. Individuals equipped with radio transmitters had a lower estimated daily survival (0.78; 95% confidence interval = 0.70–0.85) compared to wing‐marked individuals (0.89; 95% confidence interval = 0.85–0.92). Wing loading and age were the main variables influencing dragonfly survival for both methods. The probability of movement between ponds was similar for both sexes, but radio‐tracking data showed that females moved significantly further away in the landscape matrix than males, with one female detected up to 1,902 m away from the release pond. Females also had a larger home range (mean 95% kernel: 50 ha) than males (mean 95% kernel: 5 ha). Reproductive behaviour of males and flying behaviour of females were positively related to air temperature. Individuals of both sexes were present on ponds more often than in all other habitats whatever their activity. High trees were the preferred place to rest when air temperatures were low, especially for females. Overall, this study highlights the importance of integrating neighbouring trees in management schemes of ponds. It also confirms that preservation of pond networks must include on several hectares of land around ponds to meet the aquatic and terrestrial needs of amphibious organisms such as odonates. Our radio‐tracking data provide a basis for further studies on the persistence of odonate meta‐populations in fragmented landscapes.

Evidence for pollination ecotypes in the African cycadEncephalartos ghellinckii(Zamiaceae)

AbstractGeographical variation in pollinator assemblages can result in divergent selective pressures and consequently drive the evolution of phenotypically distinct pollination ecotypes. Intraspecific divergence in pollination systems is well known among angiosperms, but is poorly studied among gymnosperms, often considered a relictual group not undergoing recent radiations. We investigated whether geographical divergence in the chemistry of volatiles emitted by cones of the cycad Encephalartos ghellinckii can be linked with functions for attracting different pollinators. We tested the pollination effectiveness of different insects in terms of deposition of fluorescent dye on micropyles and investigated whether daily fluctuations in cone temperature are correlated with insect pollinator activity. We also performed field bioassays to test the responses of insects to key volatiles and laboratory y-maze experiments to determine whether insects discriminate among cones of the two forms. Experiments confirmed that the beetles Metacucujus goodei and Erotylidae sp. nov. are the most effective pollinators of the mountain and lowland forms, respectively. A peak in cone temperatures in the afternoon was associated with extensive movement of insects among cones of mountain plants, but only limited movement of insects among cones of lowland plants. In field bioassays, Metacucujus goodei beetles were attracted mainly to (3E)-1,3-octadiene, a dominant component of the scent of mountain plants, whereas Erotylidae sp. nov. responded to camphene, a dominant component of the scent of lowland plants. When offered a choice, beetles preferred cones from the local population over those from a different population. The results suggest that E. ghellinckii consists of two pollination ecotypes with modifications in scent chemistry being correlated with an apparent shift between different pollinators. The relationship between thermogenesis and pollinator activities varies between ecotypes, with mountain plants showing a push–pull type of system and the lowland plants a system in which insects depart from cones with declining quality. This study highlights the role of insect pollinators in driving the evolution of cycads and the importance of thermogenesis and volatile emissions for mediating some beetle pollination systems.

INFECTIVITY OF BEAUVERIA BASSIANA (BALSAMO) AGAINST TRIBOLIUM CASTANEUM (COLEOPTERA: TENEBRIONIDAE)

Tribolium castaneum is a major pest in wheat flour but can attack other processed foodstuffs. Control of these pests can be done in various ways, one of them by biological control using entomopathogenic fungus Beauveria bassiana. This study aims to determine the infectivity of B. bassiana entomopathogenic fungus against T. castaneum populations in the laboratory. The experiment was completed with random preparations, each preparation was repeated three times. Imago T. castaneum was sprayed with a conidia suspension of B. bassiana at a density of 106 and 107 conidia/mL on three different storage media namely PDA, rice, and corn media. Mortality was calculated based on the percentage of imago that died of B. bassiana fungi. One week observation showed the mortality of T. castaneum after the application of B. bassiana fungus was 55.33% with 107 conidia/mL in corn media. The highest spore density was found in rice media with an average of 10.53 x 106 conidia/mL. Meanwhile, the value of the results showed LC50 of 2.11 x 107 conidia/mL and the fastest LT50 in corn media was 5.31 days

Novel Method for Analyzing Flexible Locomotion Patterns of Animals by Using Polar Histogram

In general, legged robots are designed to walk with a fixed rhythmic pattern. However, most animals can adapt their limb movements while walking. It is necessary to understand the mechanism of adaptability during locomotion when designing bio-inspired legged robots. In this paper, we propose an approach to analyze the flexible locomotion pattern of animals using a polar histogram. Field crickets were used to investigate variations in leg movement of insects depending on the environment. Crickets have a tripod gait; however, their leg movement changes depending on the texture of the ground. There was a significant difference between the leg movement when walking and when swimming. Our approach can explain how animals move their legs during locomotion. This study is useful for evaluating the movements of legged robots.

Sand and shine: an inexpensive method to measure terrestrial arthropod movement in the laboratory

AbstractUnderstanding what drives insect movement is crucial to understanding how they might be affected by environmental or human disturbances. Methods that measure movement can be expensive, and few are available that do not rely on some sort of video footage. We developed a relatively inexpensive method that allows the user to see the full path of the individual insects within an arena after a certain amount of time, which can be captured with a photograph and later analysed with computer software applications. In our proof-of-concept experiment, we found that the ground beetle, Harpalus rufipes (Coleoptera: Carabidae), was more active in darkness and in light than in ultraviolet light and that it displayed different movement patterns under all three light treatments.

Insect flight velocity measurement with a CW near-IR Scheimpflug lidar system.

Flight velocity measurement is an important aspect of insect research that can aid insect identification and facilitate studies and monitoring of insect movements. We propose a novel scheme for the 1-D flight velocity measurement of insects, based on a near-IR Scheimpflug lidar system. We implement this new technique and apply it to study insects at the Salter Research Farm, Robertson County, Texas. The resolution property perpendicular to the probing direction of the Scheimpflug lidar system is explored and reveals the capability of retrieving the velocity component normal to the probing direction of insects passing through the field of view of our system. We observe a shift in wingbeat frequency, which indicates the presence of new insect species during the multi-day measurement. The study on 1-D flight velocity reveals a net directional movement of insects, providing supportive evidence of the arrival of a new species.

A generalized transition model for grouped longitudinal categorical data.

Transition models are an important framework that can be used to model longitudinal categorical data. They are particularly useful when the primary interest is in prediction. The available methods for this class of models are suitable for the cases in which responses are recorded individually over time. However, in many areas, it is common for categorical data to be recorded as groups, that is, different categories with a number of individuals in each. As motivation we consider a study in insect movement and another in pig behaviou. The first study was developed to understand the movement patterns of female adults of Diaphorina citri, a pest of citrus plantations. The second study investigated how hogs behaved under the influence of environmental enrichment. In both studies, the number of individuals in different response categories was observed over time. We propose a new framework for considering the time dependence in the linear predictor of a generalized logit transition model using a quantitative response, corresponding to the number of individuals in each category. We use maximum likelihood estimation and present the results of the fitted models under stationarity and non-stationarity assumptions, and use recently proposed tests to assess non-stationarity. We evaluated the performance of the proposed model using simulation studies under different scenarios, and concluded that our modeling framework represents a flexible alternative to analyze grouped longitudinal categoricaldata.

Morphology and Material Composition of the Mouthparts of Stromatium unicolor Olivier 1795 (Coleoptera: Cerambycidae) for Bionic Application

Research Highlights: The novelty of this study is the deep analysis of the morphologic, geometric and mechanical performance of longhorn beetle larvae mouthparts. Furthermore, a metal nano identification of jaw reinforced parts was made. Background and Objectives: Analysis of insect mechanical properties has shown an important application in the develop of bionic technologies such as new materials, industrial machines and structural concepts. This study aims to determine the mechanical and geometric properties of longhorn beetle (Stromatium unicolor Olivier 1795) larvae mouthparts to improve the development of innovative cutting tools. In addition, this study obtains a nano identification of metals in the cuticle of the mouthparts, which will enable the development of new nontoxic and sustainable preservation agents against xylophagous insects based on nanoparticles. Materials and Methods: five third-larval-stage samples of Stromatium unicolor were used to study its mandible morphologic, geometric and mechanical properties. To this end, mouthparts were analyzed by several microscopic techniques using a scanning electron microscope, a stereomicroscope and an optical microscope. Composition analysis was performed using with two Analytical-Inca X-ray detectors, dispersive energy spectroscopy and dispersive wavelength spectroscopy. Results: The main geometric parameters of the insect jaw are the edge angle (β = 77.3°), maximum path depth of the insect (120 μm), length (800 µm) and mouthpart movement, which were identified and measured. The chemical analysis results of the jaw tissues shows the presence of zinc and manganese. Conclusions: The geometry and angles of the mouthparts can be applied in the fabrication of bionic self-sharpening cutting tools. Molecular compounds that form the reinforcing elements in the jaws can be used to develop wood preservatives based on nanometals and metal absorption and metabolism inhibitors.

Seasonal insect migrations: massive, influential, and overlooked

During seasonal changes around the globe, trillions of insects are on the move. Many insect populations, including butterflies, moths, hoverflies, and dragonflies, make repeated seasonal migrations each year. It is only during the past century that biologists have come to accept the concept of insect migration, and new research using radar, citizen science, and stable isotopes has revealed unexpected insights about this phenomenon. Drawing on these findings, we demonstrate how seasonal insect movements are both massive and ecologically influential, with consequences for food webs, nutrient transport, pollination, and infectious disease. Responding to environmental changes, some mobile insect populations are declining or shifting the timing and extent of their journeys. We suggest research and policy priorities for investigating and protecting insect migrations. Outcomes from such work could transform strategies for agricultural pest control and wildlife conservation, and could help preserve the ecological functions performed by migratory insects.

Structure Design of Multi-joint Bionic Robot Based on Solidworks

The body structure of the multi joint bionic robot is designed and analyzed. According to the movement form of snake and caterpillar, a multi joint bionic robot is designed and manufactured based on the principle of bionics. Using SolidWorks software to establish the model, there are three parts: head joint, body joint and tail joint. The bionic robot uses 3D technology to be printed and make a physical prototype, and experiment with the prototype. It can imitate the movement of snakes and caterpillars, and realize snake movement, insect movement, turning, curling, lurking and other movements. Through the structural design, processing and manufacturing of the multi joint bionic robot, the movement shape is analyzed and adjusted to make its movement attitude completely similar to the biological shape.

Plants meet machines: Prospects in machine learning for plant biology

Plants meet machines: Prospects in machine learning for plant biology

Efficacy of essential oil from Clausena anisata and its impact on biochemical changes of Sitophilus oryzae.

Essential oil (EO), from Clausena anisata, was evaluated for their efficacy (fumigant and repellent activities) against Sitophilus oryzae. Result revealed that C. anisata showed 82% fumigant toxicity (insect mortality) at 160μL/L concentration after 24h observation period. C. anisata exhibited LC50 value of 17.84μL/L concentration for fumigant toxicity. The insect movement behaviour (repellent) was observed in two different concentrations of 10 and 50μL for a period of 3h. Maximum repellent activity (- 0.25) was observed at 50μL/L concentration against S. oryzae after 3-h observation. At 3, 6 and 12μL/L concentrations of C. anisata oil significantly reduced the protein content and total esterase activity of S. oryzae.

Vertical farming systems bring new considerations for pest and disease management

AbstractVertical farming is an emerging area of food production that aims to provide sustainable intensification of agriculture by maximising the obtainable yield per unit area of land. This approach commonly utilises stacked horizontal levels of crop growth in glasshouse or controlled environment (CE) facilities. Vertical farming has, however, received relatively little scientific investigation to date. Consequently, important factors such as economic feasibility, system design and optimisation of production methods are still being evaluated. Vertical farming methods bring additional considerations for the effective management of pests and diseases compared with conventional protected horticulture, such as movement of both pest and beneficial insects between growth levels. This article aims to provide a perspective on the positive and negative issues facing pest and disease control in Vertical farming systems. We highlight important considerations for system optimisation and areas for future investigation.

Evaluating the target‐tracking performance of scanning avian radars by augmenting data with simulated echoes

Abstract Small scanning radars have been used for many years to track the movements of insects, birds and bats. While the ability to track multiple flying animals simultaneously has numerous applications in basic ecology and applied conservation, translating radar tracks into accurate animal densities and fluxes requires estimates of detection and tracking probabilities. These can be challenging to determine, especially in environments with variable background clutter. In order to assess radar tracking probabilities, we added echoes from simulated bird tracks to sequences of scans collected with an X‐band marine radar at a colony of common and roseate terns (Sterna hirundo and S. dougallii) on Great Gull Island, New York, USA in the summers of 2014 and 2015. Automated detection, classification and tracking algorithms were used to extract the trajectories of terns from the radar data. The proportion of simulated tracks recovered by these procedures could then be used to estimate the tracking probabilities for real birds. Stationary telescope transects provided visual ground truth. The radar could track individual birds up to 3 km away, performing best between 0.5 and 1.2 km, where 38% of simulated birds were correctly detected and tracked in each scan. Overall, 94% of all simulated birds were tracked over at least part of their trajectories. Tracking performance was limited by weak bird echoes, backscatter from the sea surface and the inherent challenges of multi‐target tracking. This simulation‐based method provides a low‐cost, flexible approach for estimating radar‐tracking probabilities in complex, cluttered environments. Knowledge of these probabilities in turn allows the animal densities and fluxes to be corrected for imperfect detection. Despite their limitations, small scanning radars can track hundreds of birds simultaneously over tens of km2, giving a view of animal movement unavailable with other techniques.

Online tracking of ants based on deep association metrics: method, dataset and evaluation

Tracking movement of insects in a social group (such as ants) is challenging, because the individuals are not only similar in appearance but also likely to perform intensive body contact and sudden movement adjustment (start/stop, direction changes). To address this challenge, we introduce an online multi-object tracking framework that combines both the motion and appearance information of ants. We obtain the appearance descriptors by using the ResNet model for offline training on a small (N=50) sample dataset. For online association, a cosine similarity metric computes the matching degree between historical appearance sequences of the trajectory and the current detection. We validate our method in both indoor (lab setup) and outdoor video sequences. The results show that our model obtains 99.3% ± 0.5% MOTA and 91.9% ± 2.1% MOTP across 24,050 testing samples in five indoor sequences, with real-time tracking performance. In an outdoor sequence, we achieve 99.3% MOTA and 92.9% MOTP across 22,041 testing samples. The datasets and code are made publicly available for future research in relevant domains.