Insects

9 pages, 1639 KB

Open AccessArticle

The Increased Abundance of Commensal Microbes Decreases Drosophila melanogaster Lifespan through an Age-Related Intestinal Barrier Dysfunction

by Hye-Yeon Lee, Shin-Hae Lee and Kyung-Jin Min

Insects 2022, 13(2), 219; https://doi.org/10.3390/insects13020219 - 21 Feb 2022

Cited by 9 | Viewed by 3627

Abstract

Background: Commensal microbiota live in their host with a symbiotic relationship that affects the host’s health and physiology. Many studies showed that microbial load and composition were changed by aging and observed that increasing the abundance and changing the composition of commensal microbes [...] Read more.

Background: Commensal microbiota live in their host with a symbiotic relationship that affects the host’s health and physiology. Many studies showed that microbial load and composition were changed by aging and observed that increasing the abundance and changing the composition of commensal microbes had detrimental effects on host lifespan. We hypothesized that dysbiosis of the intestinal microbiota leads to systemic effects in aging flies as a result of the increased intestinal permeability. Methods: We used the fruit fly, Drosophila melanogaster, laboratory strains w¹¹¹⁸, as a model system with many advantages for microbe–host studies. Results: The incidence of intestinal dysfunction was increased with age, and intestinal dysfunction increased the permeability of the fly intestine to resident microbes. The lifespan of flies with an intestinal barrier dysfunction was increased by removal of the microbes. Interestingly, some bacteria were also found in the hemolymph of flies with intestinal barrier dysfunction. Conclusion: Our findings suggest the possibility that, as the host ages, there is an increase in intestinal permeability, which leads to an increased intestinal microbial load and a reduction in the host lifespan. Our data therefore indicate a connection between commensal microbes and host lifespan. Full article

(This article belongs to the Special Issue The Insect Gut Barrier)

► Show Figures

Figure 1

17 pages, 6058 KB

Open AccessArticle

The First Fossil Representatives of the Sawfly Genera Emphytus and Empria from the upper Miocene of France (Hymenoptera, Tenthredinidae)

by André Nel, Rose Marie Sammut, Meicai Wei, Gengyun Niu and Corentin Jouault

Insects 2022, 13(2), 218; https://doi.org/10.3390/insects13020218 - 21 Feb 2022

Cited by 8 | Viewed by 3870

Abstract

Emphytusmiocenicus sp. nov., first fossil representative of this genus, is described from the upper Miocene of the diatom paleolake of Montagne d’Andance (Ardèche, France). Its placement is ensured by an in-depth comparison with all the extant and fossil genera of the subfamily [...] Read more.

Emphytusmiocenicus sp. nov., first fossil representative of this genus, is described from the upper Miocene of the diatom paleolake of Montagne d’Andance (Ardèche, France). Its placement is ensured by an in-depth comparison with all the extant and fossil genera of the subfamily Allantinae. The representatives of Emphytus are distributed in the Palearctic, Nearctic, and Oriental regions. Empria sammuti sp. nov., second representative of the latter genus, is described from the latest Miocene of the diatom paleolake of Sainte-Reine (Cantal, France). The placement of this new species is based on a detailed comparison with the extant genera of the tribe Empriini. The larvae of the extant Emphytus and Empria spp. are known to be phytophagous on angiosperm leaves of several families, all present as fossils in the taphocenoses of la Montagne d’Andance and Sainte-Reine. Emphytus miocenicus sp. nov. represents the oldest record of this genus and of its crown group, corroborating the estimate of a middle Eocene–middle Oligocene age for its stem group. Throughout our study, it appears that the first described fossil of the genus Empria, E. oligocaenica, from the Oligocene of Germany, needs to be revised and redescribed. It should preferably be treated until the revision as incertae sedis in Allantinae sensu lato. Full article

(This article belongs to the Special Issue Fossil Insects: From Carboniferous to Quaternary)

► Show Figures

Figure 1

11 pages, 1521 KB

Open AccessArticle

Genetic Differences among Established Populations of Aromia bungii (Faldermann, 1835) (Coleoptera: Cerambycidae) in Japan: Suggestion of Multiple Introductions

by Shigeaki Tamura and Etsuko Shoda-Kagaya

Insects 2022, 13(2), 217; https://doi.org/10.3390/insects13020217 - 21 Feb 2022

Cited by 8 | Viewed by 4291

Abstract

Aromia bungii (Faldermann) (Coleoptera: Cerambycidae) is an invasive pest, damaging Rosaceae trees (particularly Prunus) in Japan and Europe. The establishment of this beetle in Japan was first detected in 2012, and subsequently, it has rapidly expanded its distribution. Currently, Japanese populations of [...] Read more.

Aromia bungii (Faldermann) (Coleoptera: Cerambycidae) is an invasive pest, damaging Rosaceae trees (particularly Prunus) in Japan and Europe. The establishment of this beetle in Japan was first detected in 2012, and subsequently, it has rapidly expanded its distribution. Currently, Japanese populations of A. bungii are widely distributed in six non-contiguous regions. In this study, we compared the nucleotide sequences of mitochondrial cytochrome oxidase subunit 1 of the populations in these six regions in Japan to examine whether multiple introductions or human-mediated long-distance dispersal have contributed to the non-contiguous distribution of A. bungii. Seven haplotypes were detected from Japanese populations, and one of these was identical to a sequence deposited from China. One to two haplotypes were detected in each region, suggesting a genetic bottleneck. Detected haplotypes differed between introduced regions, although two regions shared a single haplotype. These results suggest that multiple independent introductions of A. bungii have contributed to its non-contiguous distribution in Japan. Quarantine measures for wood-packing materials in trade need to be strengthened to prevent the establishment of further populations of A. bungii. Full article

(This article belongs to the Collection Biology and Control of the Invasive Wood-Boring Beetles)

► Show Figures

Figure 1

8 pages, 1365 KB

Open AccessCommunication

Wolbachia in Aedes koreicus: Rare Detections and Possible Implications

by Claudia Damiani, Alessia Cappelli, Francesco Comandatore, Fabrizio Montarsi, Aurelio Serrao, Alice Michelutti, Michela Bertola, Maria Vittoria Mancini, Irene Ricci, Claudio Bandi and Guido Favia

Insects 2022, 13(2), 216; https://doi.org/10.3390/insects13020216 - 21 Feb 2022

Cited by 7 | Viewed by 3084

Abstract

The emerging distribution of new alien mosquito species was recently described in Europe. In addition to the invasion of Aedes albopictus, several studies have focused on monitoring and controlling other invasive Aedes species, as Aedes koreicus and Aedes japonicus. Considering the [...] Read more.

The emerging distribution of new alien mosquito species was recently described in Europe. In addition to the invasion of Aedes albopictus, several studies have focused on monitoring and controlling other invasive Aedes species, as Aedes koreicus and Aedes japonicus. Considering the increasing development of insecticide resistance in Aedes mosquitoes, new control strategies, including the use of bacterial host symbionts, are proposed. However, little is known about the bacterial communities associated with these species, thus the identification of possible candidates for Symbiotic Control is currently limited. The characterization of the natural microbiota of field-collected Ae. koreicus mosquitoes from North-East Italy through PCR screening, identified native infections of Wolbachia in this species that is also largely colonized by Asaia bacteria. Since Asaia and Wolbachia are proposed as novel tools for Symbiotic Control, our study supports their use for innovative control strategies against new invasive species. Although the presence of Asaia was previously characterized in Ae. koreicus, our study characterized this Wolbachia strain, also inferring its phylogenetic position. The co-presence of Wolbachia and Asaia may provide additional information about microbial competition in mosquito, and to select suitable phenotypes for the suppression of pathogen transmission and for the manipulation of host reproduction in Ae. koreicus. Full article

(This article belongs to the Section Insect Physiology, Reproduction and Development)

► Show Figures

Figure 1

10 pages, 19949 KB

Open AccessCase Report

The Postmortem Interval of Two Decedents and Two Dog Carcasses at the Same Scene Based on Forensic Entomology

by Liangliang Li, Yinghui Wang, Mingqing Liao, Yanan Zhang, Chengtao Kang, Gengwang Hu, Yi Guo and Jiangfeng Wang

Insects 2022, 13(2), 215; https://doi.org/10.3390/insects13020215 - 21 Feb 2022

Cited by 9 | Viewed by 3828

Abstract

In this paper, we report the estimation of the minimum PMIs of two human corpses and two dog carcasses using entomological evidence. Corpses of an elderly couple and carcasses of four dogs were found scattered on different floors in a house. The scene [...] Read more.

In this paper, we report the estimation of the minimum PMIs of two human corpses and two dog carcasses using entomological evidence. Corpses of an elderly couple and carcasses of four dogs were found scattered on different floors in a house. The scene was very dirty. In addition, there were 12 emaciated live dogs at the scene. The corpses had been eaten by the dogs to different degrees, but the damage was greater on the man’s corpse. After forensic examination, it was concluded that both individuals died of natural causes. The minimum PMIs of the two individuals and the two dogs were estimated using entomological evidence. The minimum PMIs of the other two dogs were not estimated because of the risk of contamination with the human corpses. Different insect species were found on each of the corpses and carcasses. The minimum PMIs were estimated as about 8.75 days for the woman, 4.17 days for the man, 3.13 days for the dog found in the stairwell and about 28.80 days for the dog found in the toilet. These estimations coincided with the time the woman stopped communicating with her daughter and when the electricity consumption at the house decreased significantly. Full article

(This article belongs to the Special Issue Advanced Research on Forensic Entomology)

► Show Figures

Figure 1

12 pages, 11139 KB

Open AccessArticle

Diversity and Molecular Evolution of Odorant Receptor in Hemipteran Insects

by Jiahui Tian, Youssef Dewer, Haoyuan Hu, Fengqi Li, Shiyong Yang and Chen Luo

Insects 2022, 13(2), 214; https://doi.org/10.3390/insects13020214 - 21 Feb 2022

Cited by 13 | Viewed by 4137

Abstract

Olfaction is a critical physiologic process for insects to interact with the environment, especially plant-emitted volatiles, during which odorant receptors (ORs) play an essential role in host recognition. Although OR gene evolution has been studied in many insect orders, a comprehensive evolutionary analysis [...] Read more.

Olfaction is a critical physiologic process for insects to interact with the environment, especially plant-emitted volatiles, during which odorant receptors (ORs) play an essential role in host recognition. Although OR gene evolution has been studied in many insect orders, a comprehensive evolutionary analysis and expression of OR gene gain and loss events among diverse hemipteran species are still required. In this study, we identified and analyzed 887 OR genes from 11 hemipteran species. The number of OR genes discovered in each species ranged from less than ten to hundreds. Phylogenetic analysis revealed that all identified Hemiptera OR genes were classified into seven major clades. Gene gain and loss events of OR have occurred in several species. Then, by positive selection, we discovered the amino acid differences between species to understand the molecular evolution of OR in the order Hemiptera. Additionally, we discussed how evolutionary analysis can aid the study of insect–plant communication. This study lays a foundation for subsequent investigations into the molecular mechanisms of Hemiptera olfactory receptors involved in host recognition. Full article

(This article belongs to the Special Issue Chemosensory Genes in Insects)

► Show Figures

Figure 1

11 pages, 1248 KB

Open AccessArticle

Field and Laboratory Efficacy of Low-Impact Commercial Products in Preventing Olive Fruit Fly, Bactrocera oleae, Infestation

by Elissa Daher, Nicola Cinosi, Elena Chierici, Gabriele Rondoni, Franco Famiani and Eric Conti

Insects 2022, 13(2), 213; https://doi.org/10.3390/insects13020213 - 21 Feb 2022

Cited by 15 | Viewed by 3945

Abstract

The olive fruit fly, Bactrocera oleae, is the key pest of olive trees in several areas of the world. Given the need for the development of sustainable control methods, preventive tools, based on the manipulation of pest behaviour, must be considered. Here, [...] Read more.

The olive fruit fly, Bactrocera oleae, is the key pest of olive trees in several areas of the world. Given the need for the development of sustainable control methods, preventive tools, based on the manipulation of pest behaviour, must be considered. Here, under field and laboratory conditions, we tested the efficacy of different products in preventing B. oleae infestation. A field trial was conducted, from July to November 2020, in an olive orchard located in Central Italy. A table olive variety was selected and sprayed with rock powder, propolis, the mixture of both, copper oxychloride, or water (control). All treatments, except propolis, caused a reduction of B. oleae oviposition in olives, compared to the control. The mixture allowed the strongest reduction of fly infestation throughout the season, suggesting a synergistic effect. Behavioural no-choice assays were conducted to better understand the effects of treatments on B. oleae females. Compared to the control, females showed a lower preference for the central area of an arena containing an olive twig bearing two olive fruits, fully developed, but still green, treated with rock powder, plus propolis mixture. For all treatments, B. oleae showed lower oviposition events, suggesting deterrence to oviposition. Our results indicate that the tested products may have value against B. oleae, within integrated pest management (IPM) and organic agriculture. Full article

(This article belongs to the Section Insect Pest and Vector Management)

► Show Figures

Figure 1

16 pages, 701 KB

Open AccessArticle

A Route to Translate a Silk-Based Medical Device from Lab to Clinic: The Silk Biomaterials Srl Experience

by Giulia Alessandra Bassani, Valentina Vincoli, Marco Biagiotti, Elisa Valsecchi, Marta Virginia Zucca, Claudia Clavelli, Antonio Alessandrino and Giuliano Freddi

Insects 2022, 13(2), 212; https://doi.org/10.3390/insects13020212 - 21 Feb 2022

Cited by 8 | Viewed by 3490

Abstract

The medical device is a nerve conduit entirely made of Bombyx mori silk fibroin. It is a tubular scaffold used for repairing peripheral nerve gaps, whose function is to protect the severed nerves and to favor their natural healing process. As any implantable [...] Read more.

The medical device is a nerve conduit entirely made of Bombyx mori silk fibroin. It is a tubular scaffold used for repairing peripheral nerve gaps, whose function is to protect the severed nerves and to favor their natural healing process. As any implantable medical device, the conduit must perform its function without causing adverse effects to the patient, meaning that it must be compliant with a range of regulations aimed at evaluating the risks related to the constituent materials and the manufacturing process, the toxicological impact of the processing aids, the biological safety, the functional performance, and the ability to sustain tissue regeneration processes. An exhaustive on-bench testing plan has been performed for the determination of the morphological, geometrical, physical, structural, and mechanical properties. For the toxicological analysis, the device was extracted with solvent and the number of leachable substances was determined by suitable chromatographic techniques. The biological safety was assessed by means of a set of tests, including cytotoxicity, delayed hypersensitivity, intracutaneous reactivity, pyrogen test, LAL (Limulus Amebocyte Lysate) test, acute systemic toxicity, and genotoxicity. Overall, the accumulated results demonstrated the suitability of the device for the intended use and supported the starting of a first-in-human clinical trial. Full article

(This article belongs to the Special Issue Silkworm and Silk: Traditional and Innovative Applications)

► Show Figures

Graphical abstract

15 pages, 1302 KB

Open AccessArticle

The Effect of Temperatures and Hosts on the Life Cycle of Spodoptera frugiperda (Lepidoptera: Noctuidae)

by Yi-Chai Chen, De-Fei Chen, Mao-Fa Yang and Jian-Feng Liu

Insects 2022, 13(2), 211; https://doi.org/10.3390/insects13020211 - 20 Feb 2022

Cited by 40 | Viewed by 5698

Abstract

The interactions between ambient temperatures and host plants are central to the population dynamics of invasive animal species. Despite significant research into the effects of temperatures, the performance of invasive species is also influenced by host plants. The effects of different temperatures (20, [...] Read more.

The interactions between ambient temperatures and host plants are central to the population dynamics of invasive animal species. Despite significant research into the effects of temperatures, the performance of invasive species is also influenced by host plants. The effects of different temperatures (20, 25, and 30 °C) and host plants (maize, sorghum, and coix seed) were tested on the mortality, development, reproduction, and population parameters of the fall armyworm (FAW), Spodoptera frugiperda (J E Smith) (Lepidoptera: Noctuidae), using an age-stage, two-sex life table. The results support the hypothesis that temperature and the species of the host plant significantly influences the performance of FAW. Feeding on maize at 30 °C resulted in a lower mortality rate, a shorter developmental time and longevity, a higher fecundity, intrinsic rate of natural increase (r), finite rate of increase (λ), and net reproductive rate (R₀). However, at 20 °C, the host plant could eliminate temperature-mediated synergism in FAW performance, which did not reach statistical significance at 20 °C. Similar results induced by a relatively low temperature (20 °C) on different host plants were also found in the age-stage specific survival curves (s_xj), fecundity (m_x), maternity (l_xm_x), and reproductive value (v_xj) curves of FAW. Consequently, we also need to pay more attention to FAW outbreaks on different host plants mediated by relatively low temperatures. Full article

► Show Figures

Figure 1

14 pages, 5726 KB

Open AccessArticle

The Phylogenetic Relationships of the Fanniidae within the Muscoid Grade (Diptera: Calyptrata) Based on the Musculature of the Male Terminalia

by Vera S. Sorokina and Olga G. Ovtshinnikova

Insects 2022, 13(2), 210; https://doi.org/10.3390/insects13020210 - 18 Feb 2022

Cited by 4 | Viewed by 2716

Abstract

The abdominal and pregenital segments and the genitalia were studied in males of Fannia subpellucens (Zetterstedt, 1845), Fannia canicularis (Linnaeus, 1761) and Fannia incisurata (Zetterstedt, 1838). In comparison with the remaining members of the muscoid grade, in addition to the symmetry of the [...] Read more.

The abdominal and pregenital segments and the genitalia were studied in males of Fannia subpellucens (Zetterstedt, 1845), Fannia canicularis (Linnaeus, 1761) and Fannia incisurata (Zetterstedt, 1838). In comparison with the remaining members of the muscoid grade, in addition to the symmetry of the pregenital segments, significant reductions of the sclerites and musculature of the male terminalia have been observed in Fanniidae. The muscular structure of pregenital segments confirms that the fused pregenital ring is syntergosternite VI + VII + VIII. Symmetry and fusion, as well as the lower number of the sclerites and muscles of the pregenital segments and male genitalia of the Fanniidae, can be considered apomorphic character states. The presence of the lateral bacilliform sclerite, as well as the presence and position of the epandrial muscles M 26, three pairs of muscles M 19 and paired muscles M 18, can be considered as a plesiomorphic character state of the Fanniidae. The structure of the sclerites and muscles of the male abdominal segments and terminalia place the Fanniidae at the base of the muscoid grade and Oestroidea, as has been confirmed by recent molecular studies. Full article

(This article belongs to the Collection Advances in Diptera Biology)

► Show Figures

Figure 1

10 pages, 1328 KB

Open AccessArticle

Middle-Aged Worker Bees Express Higher Innate Immunity than Young Worker Bees in the Abdomen without the Digestive Tract of Worker Bees Reared in an Incubator

by Yi-Wen Lin, Chia-Hsiang Chen and Chin-Yuan Hsu

Insects 2022, 13(2), 209; https://doi.org/10.3390/insects13020209 - 18 Feb 2022

Cited by 5 | Viewed by 2570

Abstract

Honey bees (Apis mellifera) can be reared in an incubator to study the mechanisms of aging and longevity; however, whether breeding in an incubator and using the abdomen without the digestive tract influences the expression of immune genes is unclear. In [...] Read more.

Honey bees (Apis mellifera) can be reared in an incubator to study the mechanisms of aging and longevity; however, whether breeding in an incubator and using the abdomen without the digestive tract influences the expression of immune genes is unclear. In this study, we assayed the immune genes including abaecin, hymenoptaecin, defensin-2, glucose dehydrogenase, phenoloxidase, and lysozyme from the whole body of young and middle-aged worker bees reared in field hives, the whole body of young and middle-aged worker bees reared in a 34 °C incubator, and the abdomen without the digestive tract of young and middle-aged worker bees reared in a 34 °C incubator. The results showed that three groups of middle-aged worker bees have higher immunity than young worker bees. Furthermore, the similarity of immune genes expression in three groups indicated that the abdomen without the digestive tract of honey bees reared in an incubator can be used to study the relationship between immunity and aging and longevity to avoid the interference of pathogens and parasites from field hives. Full article

► Show Figures

Figure 1

19 pages, 1955 KB

Open AccessArticle

Studies on the Volatiles Composition of Stored Sheep Wool, and Attractancy toward Aedes aegypti Mosquitoes

by Maia Tsikolia, Nurhayat Tabanca, Daniel L. Kline, Betul Demirci, Liu Yang, Kenneth J. Linthicum, Jeffrey R. Bloomquist and Ulrich R. Bernier

Insects 2022, 13(2), 208; https://doi.org/10.3390/insects13020208 - 18 Feb 2022

Cited by 3 | Viewed by 3548

Abstract

To discover new natural materials for insect management, commercially available stored sheep wool was investigated for attractancy to female adult Aedes aegypti mosquitoes. The volatiles from sheep wool were collected by various techniques of headspace (HS) extractions and hydrodistillation. These extracts were analyzed [...] Read more.

To discover new natural materials for insect management, commercially available stored sheep wool was investigated for attractancy to female adult Aedes aegypti mosquitoes. The volatiles from sheep wool were collected by various techniques of headspace (HS) extractions and hydrodistillation. These extracts were analyzed using gas chromatography–mass spectrometry (GC-MS) and gas chromatography–flame ionization detector (GC-FID) coupled with GC-MS. Fifty-two volatile compounds were detected, many of them known for their mosquito attractant activity. Seven compounds were not previously reported in sheep products. The volatile composition of the extracts varied significantly across collections, depending on the extraction techniques or types of fibers applied. Two types of bioassay were conducted to study attractancy of the sheep wool volatiles to mosquitoes: laboratory bioassays using glass tubes, and semi-field bioassays using large, screened outdoor cages. In bioassays with glass tubes, the sheep wool hydrodistillate and its main component, thialdine, did not show any significant attractant activity against female adult Ae. aegypti mosquitoes. Semi-field bioassays in two large screened outdoor cages, each equipped with a U.S. Centers for Disease Control (CDC) trap and the various bait setups with Vortex apparatus, revealed that vibrating wool improved mosquito catches compared to the setups without wool or with wool but not vibrating. Sheep wool, when vibrated, may release intensively volatile compounds, which could serve as olfactory cues, and play significant role in making the bait attractive to mosquitoes. Sheep wool is a readily available, affordable, and environment-friendly material. It should have the potential to be used as a mosquito management and surveillance component in dynamic bait setups. Full article

(This article belongs to the Special Issue Vector-Borne Diseases in a Changing World)

► Show Figures

Figure 1

20 pages, 5270 KB

Open AccessArticle

Material Properties and Morphology of Prestomal Teeth in Relation to the Feeding Habits of Diptera (Brachycera)

by Matthew S. Lehnert, Lauren A. Tarver and Jiansheng Feng

Insects 2022, 13(2), 207; https://doi.org/10.3390/insects13020207 - 17 Feb 2022

Cited by 12 | Viewed by 3764

Abstract

Prestomal teeth are cuticular projections on the mouthparts of some fly species that rasp surfaces when feeding. Although prestomal teeth morphology has been reported for several fly species, their material properties have not been investigated. Here we report the morphology, elemental composition, extent [...] Read more.

Prestomal teeth are cuticular projections on the mouthparts of some fly species that rasp surfaces when feeding. Although prestomal teeth morphology has been reported for several fly species, their material properties have not been investigated. Here we report the morphology, elemental composition, extent of sclerotization, hardness, and elastic modulus of prestomal teeth and relate these findings to feeding habits. Scanning electron microscopy revealed that species categorized as flower visitors have a large labellum with numerous pseudotracheae and lack prestomal teeth, generalist species have these same features but with prestomal teeth, and specialist species that feed on blood or other insects have a smaller labellum with few or no pseudotracheae and relatively large prestomal teeth. Confocal microscopy revealed that prestomal teeth are heavily sclerotized and the labellum contains resilin, an elastomeric protein. Hardness and elastic modulus were explored with nanoindentation and showed that the insectivorous Scathophaga stercoraria had the hardest prestomal teeth and the highest modulus. Energy dispersive x-ray spectroscopy revealed that prestomal teeth had low concentrations of inorganic elements, suggesting that hardness might be partially supplemented by inorganic elements. Our findings indicate that prestomal teeth morphology and material properties relate more to feeding habits than to phylogeny. Full article

(This article belongs to the Special Issue Feeding Organs in Hexapoda)

► Show Figures

Figure 1

12 pages, 1645 KB

Open AccessReview

Potential Risk of Pollen from Genetically Modified MON 810 Maize Containing Cry1Ab Toxin to Protected Lepidopteran Larvae in the Pannonian Biogeographical Region—A Retrospective View

by Béla Darvas, Gergő Gyurcsó, Eszter Takács and András Székács

Insects 2022, 13(2), 206; https://doi.org/10.3390/insects13020206 - 17 Feb 2022

Cited by 1 | Viewed by 3211

Abstract

A credible risk analysis of maize pollen containing Cry1Ab toxin must include the assessment of (i) pollen production and its Cry1 toxin content; (ii) distribution of the pollen grains in the surroundings; (iii) pollen-catching capacity of the [...] Read more.

A credible risk analysis of maize pollen containing Cry1Ab toxin must include the assessment of (i) pollen production and its Cry1 toxin content; (ii) distribution of the pollen grains in the surroundings; (iii) pollen-catching capacity of the weeds on field edges; (iv) the lifestyle of protected lepidopteran larvae living on weeds; (v) Cry1 toxin sensitivity of non-target caterpillars; and (vi) Cry1 toxin resistance of individual non-target populations. The concentration range of 5–4300 ng Cry1Ab toxin/g dry pollen determined in MON 810 pollen batches is too diverse for handling it as a single set in any mathematical modeling. Within the work carried out mainly with the DK-440 BTY cultivar, the seed samples officially received from the variety owner produced significantly different (250–470 vs. 5–15 ng/g) Cry1Ab toxin concentrations in the pollen. Nymphalis io L1-L3 larvae were nearly six times more sensitive for Dipel than Nymphalis c-album. Feeding on the back side and in a leaf nest, Vanessa atalanta may be subject to lower pollen exposures. N. io larvae may actively attempt to avoid patches with high pollen contamination. Cry1Ab toxin resistance also partially emerged in N. io populations reared in the Pannonian Biogeographical Region (Hungary). Full article

► Show Figures

Figure 1

16 pages, 1535 KB

Open AccessEditor’s ChoiceArticle

Comparative Screening of Mexican, Rwandan and Commercial Entomopathogenic Nematodes to Be Used against Invasive Fall Armyworm, Spodoptera frugiperda

by Patrick Fallet, Lara De Gianni, Ricardo A. R. Machado, Pamela Bruno, Julio S. Bernal, Patrick Karangwa, Joelle Kajuga, Bancy Waweru, Didace Bazagwira, Thomas Degen, Stefan Toepfer and Ted C. J. Turlings

Insects 2022, 13(2), 205; https://doi.org/10.3390/insects13020205 - 16 Feb 2022

Cited by 32 | Viewed by 4744

Abstract

The fall armyworm (FAW), Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is an important pest of maize originating from the Americas. It recently invaded Africa and Asia, where it causes severe yield losses to maize. To fight this pest, tremendous quantities of synthetic insecticides are [...] Read more.

The fall armyworm (FAW), Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is an important pest of maize originating from the Americas. It recently invaded Africa and Asia, where it causes severe yield losses to maize. To fight this pest, tremendous quantities of synthetic insecticides are being used. As a safe and sustainable alternative, we explore the possibility to control FAW with entomopathogenic nematodes (EPN). We tested in the laboratory whether local EPNs, isolated in the invasive range of FAW, are as effective as EPNs from FAW native range or as commercially available EPNs. This work compared the virulence, killing speed and propagation capability of low doses of forty EPN strains, representing twelve species, after placing them with second-, third- and sixth-instar caterpillars as well as pupae. EPN isolated in the invasive range of FAW (Rwanda) were found to be as effective as commercial and EPNs from the native range of FAW (Mexico) at killing FAW caterpillars. In particular, the Rwandan Steinernema carpocapsae strain RW14-G-R3a-2 caused rapid 100% mortality of second- and third-instar and close to 75% of sixth-instar FAW caterpillars. EPN strains and concentrations used in this study were not effective in killing FAW pupae. Virulence varied greatly among EPN strains, underlining the importance of thorough EPN screenings. These findings will facilitate the development of local EPN-based biological control products for sustainable and environmentally friendly control of FAW in East Africa and beyond. Full article

(This article belongs to the Special Issue Entomopathogenic Nematodes: Lethal Parasites of Insects)

► Show Figures

Figure 1

17 pages, 2288 KB

Open AccessArticle

DNA Barcoding versus Morphological Variability of Pterostichus brevicornis brevicornis (Kirby, 1837) (Coleoptera, Carabidae) in the Arctic and Subarctic

by Natalia Andreevna Zubrii, Boris Yurevich Filippov, Alexander Vasilevich Kondakov, Olga Arturovna Khruleva, Leonid Borisovich Rybalov and Darya Vitalievna Vikhreva

Insects 2022, 13(2), 204; https://doi.org/10.3390/insects13020204 - 16 Feb 2022

Cited by 5 | Viewed by 3782

Abstract

The geographic patterns of genetic and morphological variability in ground beetles were examined throughout Northern Eurasia and North America using the most abundant circumpolar tundra subspecies, Pterostichus (Cryobius) brevicornis brevicornis (Kirby, 1837), as a model. Phylogenetic structure was assessed on the basis of [...] Read more.

The geographic patterns of genetic and morphological variability in ground beetles were examined throughout Northern Eurasia and North America using the most abundant circumpolar tundra subspecies, Pterostichus (Cryobius) brevicornis brevicornis (Kirby, 1837), as a model. Phylogenetic structure was assessed on the basis of a Bayesian approach using two DNA markers (partial sequences of the COI and 28S rRNA genes), while phylogeographic patterns and population genetic diversity were estimated using the COI gene only. Morphological patterns were analysed using elliptical Fourier coefficients that were calculated based on the pronotum and male genitalia shape outlines. The subspecies shares 23 COI haplotypes throughout its entire circumpolar range, while eight haplotypes of 28S rRNA were detected in Northern Eurasia. Phylogenetic analysis did not reveal subdivided species lineages with strict geographical imprint. The network, F_ST and uncorrected pairwise divergence analyses showed that the genetic distances between populations increase by longitude from Northeastern Asia to Europe. The genetic variability among the five studied geographical population groups of P. b. brevicornis was relatively high. The MANOVA showed significant regional divergence between local populations in Northern Eurasia based on both morphological markers, but only male genitalia variability was geographically structured. Neither the pronotum shape nor the male genitalia shape aligned with the phylogeographic patterns discovered on the basis of COI sequences. The genetic (COI) marker had more variation within, rather than among, population groups in addition to morphology of pronotum but not male genitalia. Full article

► Show Figures

Figure 1

15 pages, 1004 KB

Open AccessArticle

Mosquitoes Larvicidal Activity of Ocimum kilimandscharicum Oil Formulation under Laboratory and Field-Simulated Conditions

by John Bwire Ochola, Clifford Maina Mutero, Rose Muthoni Marubu, Barbara Frei Haller, Ahmed Hassanali and Wilber Lwande

Insects 2022, 13(2), 203; https://doi.org/10.3390/insects13020203 - 16 Feb 2022

Cited by 18 | Viewed by 6647

Abstract

Mosquitoes are vectors of many severe diseases, including malaria, yellow as well as dengue fever, and lymphatic filariasis. The use of synthetic chemical insecticides for mosquito control has been associated with resistance development and detrimental human, and ecological effects. For a safer alternative, [...] Read more.

Mosquitoes are vectors of many severe diseases, including malaria, yellow as well as dengue fever, and lymphatic filariasis. The use of synthetic chemical insecticides for mosquito control has been associated with resistance development and detrimental human, and ecological effects. For a safer alternative, the emulsified Ocimum kilimandscharicum oil formulation was evaluated for its larvicidal activity. The oil was analyzed by GC and GC/MS. The formulations were evaluated against third instar mosquito larvae in the laboratory and later compared with Bacillus thuringiensis subsp. israelensis against An. gambiae under field-simulated conditions. Thirty-nine compounds were identified in the oil, the main ones being D-camphor (36.6%) and limonene (18.6%). The formulation showed significant larval mortalities against An. gambiae and An. arabiensis larvae with LC₅₀ of 0.07 and 0.31 ppm, respectively, at 24 h. Under the field-simulated trial, within 24 h, the formulation showed 98% mortality while Bti had achieved 54%. On day three, it caused 100% mortality while Bti achieved 76.5%. The high bioactivity and sublethal toxic effects to offspring of treated mosquito larvae, in terms of disruption of larval morphological aspects, suggest the high potential of the formulation as a botanical larvicide. The formulation, thus, may provide a valuable alternative for the effective and eco-friendly control of disease vectors. Full article

(This article belongs to the Section Insect Pest and Vector Management)

► Show Figures

Figure 1

13 pages, 8930 KB

Open AccessArticle

Evaluation of Methods to Collect Diurnal Culicidae (Diptera) at Canopy and Ground Strata, in the Atlantic Forest Biome

by Juliana Telles de Deus, Luís Filipe Mucci, Simone Lucheta Reginatto, Mariza Pereira, Eduardo Sterlino Bergo and Vera Lucia Fonseca de Camargo-Neves

Insects 2022, 13(2), 202; https://doi.org/10.3390/insects13020202 - 16 Feb 2022

Cited by 6 | Viewed by 2722

Abstract

Hand-held insect nets are the standard method for capturing vector mosquitoes of sylvatic arboviruses; however, occupational risks and biases due to individual skill and attractiveness are important limitations. The use of chemical attractants and automatic traps could be an alternative to resolve these [...] Read more.

Hand-held insect nets are the standard method for capturing vector mosquitoes of sylvatic arboviruses; however, occupational risks and biases due to individual skill and attractiveness are important limitations. The use of chemical attractants and automatic traps could be an alternative to resolve these limitations. This study compares the yields achieved using nets with those employing electrical traps with CO₂ and BG-Lure^®, near the ground and in the canopy strata (6.0 and 8.0 m high). The study was conducted at the Cantareira State Park, which is in the Brazilian Atlantic Forest biome. In the 18 collections performed, 3570 specimens of 52 taxa were obtained. The most frequent species captured near the ground were Wyeomyia confusa and Limatus durhamii, whereas Sabethes albiprivus, Sabethes purpureus, and Haemagogus leucocelaenus were the most frequent in the canopy. The nets resulted in greater species richness and abundance, followed by the trap employing CO₂. The combination of CO₂ traps with BG-Lure^® did not improve performance. The use of BG-Lure^® alone resulted in low abundance and a low number of species. Our results demonstrate that the use of traps with CO₂ can be complementary to collections with nets; however, for species of epidemiological interest such as those of the genera Haemagogus and Sabethes, especially in the canopy, the net remains the method of choice. Full article

(This article belongs to the Special Issue Insect Vector-Focused Approaches for Disease Control)

► Show Figures

Figure 1

15 pages, 73383 KB

Open AccessArticle

Phylogenetic Position of a New Trisetacus Mite Species (Nalepellidae) Destroying Seeds of North American Junipers and New Hypotheses on Basal Divergence of Eriophyoidea

by Philipp E. Chetverikov, Brian G. Rector, Kirk Tonkel, Lindsay Dimitri, Denis S. Cheglakov, Anna E. Romanovich and James Amrine

Insects 2022, 13(2), 201; https://doi.org/10.3390/insects13020201 - 15 Feb 2022

Cited by 5 | Viewed by 3765

Abstract

Eriophyoid mites of the genus Trisetacus Keifer are widespread parasites of conifers. A new oligophagous species, T. indelis n. sp., was discovered severely damaging seeds of North American junipers (Juniperus osteosperma, J. occidentalis, and J. californica) in [...] Read more.

Eriophyoid mites of the genus Trisetacus Keifer are widespread parasites of conifers. A new oligophagous species, T. indelis n. sp., was discovered severely damaging seeds of North American junipers (Juniperus osteosperma, J. occidentalis, and J. californica) in the western USA. It has two codon deletions in the mitochondrial gene Cox1 rarely detected in Eriophyoidea and includes distinct morphological dimorphism of females. A phylogenetic analysis based on amino acid alignment of translated Cox1 sequences using a large set of out-groups (a) determined that two North American congeners, T. batonrougei and T. neoquadrisetus, were the closest known relatives of T. indelis n. sp., and (b) indicated that Old and New World seed-inhabiting Trisetacus from junipers do not form a distinct clade, suggesting a possible independent transition to living in seeds of junipers in America and Eurasia by Trisetacus spp. Our analysis produced a new topology consistent with a scenario assuming gradual reduction of prodorsal shield setation in Eriophyoidea and an ancient switch from gymnosperms to other hosts. Additionally, our analysis did not support monophyly of Trisetacus; recovered a new host-specific, moderately supported clade comprising Trisetacus and Nalepellinae (Nalepella + Setoptus) associated with Pinaceae; and questioned the monophyly of Trisetacus associated with Cupressaceae. Full article

(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)

► Show Figures

Figure 1

18 pages, 3522 KB

Open AccessArticle

Andricus cydoniae Giraud, 1859 Junior Synonym of Cynips conifica Hartig, 1843, as Experimentally Demonstrated (Hymenoptera: Cynipidae: Cynipini)

by Salvatore Sottile, Giuliano Cerasa, Bruno Massa and Gabriella Lo Verde

Insects 2022, 13(2), 200; https://doi.org/10.3390/insects13020200 - 15 Feb 2022

Cited by 6 | Viewed by 3317

Abstract

We demonstrated the life cycle closure of Cynips conifica Hartig, 1843 (presently Andricus conificus), previously supposed on the basis of molecular data, and the identity of the sexual generation, through laboratory experiments. As a consequence, Andricus cydoniae Giraud, 1859 became a junior [...] Read more.

We demonstrated the life cycle closure of Cynips conifica Hartig, 1843 (presently Andricus conificus), previously supposed on the basis of molecular data, and the identity of the sexual generation, through laboratory experiments. As a consequence, Andricus cydoniae Giraud, 1859 became a junior synonym of A. conificus (Hartig, 1843). We provide illustrations and a diagnosis for adults and galls, observations on biology, and information on distribution. Moreover, as sexual galls of A. conificus cannot be distinguished from those of Andricus multiplicatus, a detailed comparison between sexual galls and adults of these two species is reported. Full article

► Show Figures

Figure 1

13 pages, 858 KB

Open AccessArticle

Hard Ticks (Ixodidae) from Wildlife in Liguria, Northwest Italy: Tick Species Diversity and Tick-Host Associations

by Annalisa Accorsi, Irene Schiavetti, Valeria Listorti, Monica Dellepiane, Chiara Masotti, Carlo Ercolini, Lisa Guardone and Elisabetta Razzuoli

Insects 2022, 13(2), 199; https://doi.org/10.3390/insects13020199 - 14 Feb 2022

Cited by 11 | Viewed by 3783

Abstract

Hard ticks’ geographical distribution and abundance are influenced by wildlife population. This work presents the results of the identification of ticks retrieved from wild animals in the framework of a Regional Plan of Monitoring and Surveillance of Wildlife health. The frequency of distribution [...] Read more.

Hard ticks’ geographical distribution and abundance are influenced by wildlife population. This work presents the results of the identification of ticks retrieved from wild animals in the framework of a Regional Plan of Monitoring and Surveillance of Wildlife health. The frequency of distribution of ticks in different hosts and their geographical patterns were also investigated. Ticks were collected from game animals (Sus scrofa, Capreolus capreolus, Dama dama, and Rupicapra rupicapra) during two hunting seasons (2018–2019 and 2019–2020) in the four provinces of the Liguria region in northwest Italy. In the same period, ticks were also collected from carcasses of Vulpes vulpes, Canis lupus, Meles meles, and Asio otus received for necropsy. Tick species were identified according to taxonomic keys. A total of 819 ticks, removed from 259 animals, were found and identified. Overall, Ixodes ricinus was the dominant species (62.6%), followed by Dermacentor marginatus (24.5%), Rhipicephalus sanguineus s.l. (12.5%), Haemaphysalis punctata (0.2%), and Ixodes hexagonus (0.1%). I. ricinus was also the prevalent species in roe deer and in fallow deer and the only species collected from the three wolf carcasses examined. In contrast, D. marginatus was the dominant species in S. scrofa. This last tick species was also more frequent in one province (Imperia), whereas Ixodes spp. were more common in another one (Savona). Wild animals proved to be useful for characterizing and monitoring tick population. Full article

(This article belongs to the Special Issue Vector-Borne Infections: From Ecology to Vector-Microbe-Host Interactions)

► Show Figures

Figure 1

12 pages, 1780 KB

Open AccessArticle

Intraspecific Relationships and Nest Mound Shape Are Affected by Habitat Features in Introduced Populations of the Red Wood Ant Formica paralugubris

by Filippo Frizzi, Alberto Masoni, Margherita Santedicola, Martina Servini, Nicola Simoncini, Jessica Palmieri and Giacomo Santini

Insects 2022, 13(2), 198; https://doi.org/10.3390/insects13020198 - 14 Feb 2022

Cited by 6 | Viewed by 3006

Abstract

Ants belonging to the Formica rufa group build large nest mounds, which aid their survival during severe winters. We investigated whether different environmental features of the habitats affected the nest mound shape and the population structure. We assessed the shape of all the [...] Read more.

Ants belonging to the Formica rufa group build large nest mounds, which aid their survival during severe winters. We investigated whether different environmental features of the habitats affected the nest mound shape and the population structure. We assessed the shape of all the nest mounds and mapped inter-nest trails connecting mounds for three imported populations of Formica paralugubris in three forest habitats: fir-dominated, beech-dominated, and a mixture of fir and beech. Single-nest mounds were averagely smaller and flatter in the beech-dominated forest, probably because of lighter building materials. Nonetheless, by summing the volumes of all interconnected nests, the size was similar among all three sites. In fir- and beech-dominated forests, large nests were also central in the networks, suggesting a central place foraging model with these nests as reference. We finally performed aggression tests, and found that aggressiveness was significantly higher among nests belonging to the same population than between populations. The results highlight the plasticity of the species to adapt nest and colony structure to different environments. Additionally, it appears that none of these populations is unicolonial, as observed in various alpine sites, there and the observed patterns of aggression are coherent with the ‘nasty neighbor’ effect. Full article

(This article belongs to the Section Insect Ecology, Diversity and Conservation)

► Show Figures

Figure 1

13 pages, 1887 KB

Open AccessArticle

Phlebotomine Sand Flies in Southern Thailand: Entomological Survey, Identification of Blood Meals and Molecular Detection of Trypanosoma spp.

by Jirayu Buatong, Vit Dvorak, Arunrat Thepparat, Kanaphot Thongkhao, Surachart Koyadun, Padet Siriyasatien and Theerakamol Pengsakul

Insects 2022, 13(2), 197; https://doi.org/10.3390/insects13020197 - 14 Feb 2022

Cited by 12 | Viewed by 4711

Abstract

An entomological survey at rural and cavernicolous localities in four provinces in southern Thailand provided 155 blood-fed females of sand flies (Diptera: Psychodidae) that were identified based on morphological characters as Idiophlebotomus asperulus (n = 19), Phlebotomus stantoni (n = 4), [...] Read more.

An entomological survey at rural and cavernicolous localities in four provinces in southern Thailand provided 155 blood-fed females of sand flies (Diptera: Psychodidae) that were identified based on morphological characters as Idiophlebotomus asperulus (n = 19), Phlebotomus stantoni (n = 4), P. argentipes (n = 3), Sergentomyia anodontis (n = 20), S. barraudi (n = 9), S. hamidi (n = 23), S. hodgsoni (n = 4), S. hodgsoni hodgsoni (n = 32), S. indica (n = 5), S. iyengari (n = 2), S. khawi (n = 17), S. silvatica (n = 11) and Sergentomyia sp. (n = 6). The dominant species in this study was S. hodgsoni hodgsoni, which was collected specifically in a Buddha cave. Screening for DNA of parasitic protozoans revealed eight specimens (5.16%) of four species (S. barraudi, S. indica, S. khawi and Id. asperulus) positive for Trypanosoma sp., while no Leishmania spp. DNA was detected. Blood meals of engorged females were identified by PCR-Restriction Fragment Length Polymorphism (PCR-RFLP) assay on a fragment of cytochrome b (cyt b) gene with a success rate 36%, humans, dogs, and rats being determined as sources of blood. Bloodmeal analysis of two Trypanopsoma-positive females (S. barraudi and Sergentomyia sp.) identified blood from dogs and humans, respectively. Our findings indicate that S. barraudi, S. indica, S. khawi and Id. asperulus may be incriminated in circulation of detected Trypanosoma spp. Full article

(This article belongs to the Section Insect Systematics, Phylogeny and Evolution)

► Show Figures

Figure 1

8 pages, 1411 KB

Open AccessEditor’s ChoiceArticle

The Effect of Resistance to Bt Corn on the Reproductive Output of Spodoptera frugiperda (Lepidoptera: Noctuidae)

by Natália de Souza Ribas, Jeremy N. McNeil, Hernane Dias Araújo, Bruna de Souza Ribas and Eraldo Lima

Insects 2022, 13(2), 196; https://doi.org/10.3390/insects13020196 - 14 Feb 2022

Cited by 5 | Viewed by 3669

Abstract

The fall armyworm (FAW) Spodoptera frugiperda is the most significant lepidopteran corn pest in South American countries. Transgenic Bt corn, producing the Cry1Fa toxins, has been used to control this pest, but there is clear evidence that some FAW populations have developed resistance. [...] Read more.

The fall armyworm (FAW) Spodoptera frugiperda is the most significant lepidopteran corn pest in South American countries. Transgenic Bt corn, producing the Cry1Fa toxins, has been used to control this pest, but there is clear evidence that some FAW populations have developed resistance. To determine if there are costs associated with resistance, we compared the mass of adults, the duration of mating, and the mass of the first spermatophore produced, as well as the lifetime fecundity and fertility of once-mated susceptible (SS) and resistant (RR) females. Adult mass was affected by both sex and strain, with SS females being significantly larger than RR ones, while the inverse was true for males. RR pairs took significantly longer to mate than SS pairs, yet the mass of spermatophores produced by RR males was significantly less than those of SS males. The total number of eggs laid did not differ but the fertility of eggs from once-mated RR pairs was significantly lower than that of SS pairs. Our data provided clear evidence that the development of Bt resistance affected the reproductive capacity of resistant FAW. Full article

(This article belongs to the Special Issue Applied Insect Reproductive Biology)

► Show Figures

Figure 1

11 pages, 1386 KB

Open AccessArticle

Multiplex PCR Assay for the Identification of Four Species of the Anopheles Leucosphyrus Sub-Group in Malaysia

by Sandthya Pramasivan, Jonathan Wee Kent Liew, Nantha Kumar Jeyaprakasam, Van Lun Low, Romano Ngui and Indra Vythilingam

Insects 2022, 13(2), 195; https://doi.org/10.3390/insects13020195 - 13 Feb 2022

Cited by 5 | Viewed by 4396 | Correction

Abstract

The Leucosphyrus Group of mosquitoes are the major simian malaria vectors in Malaysia. Accurate species identification is required to help in curbing the spread of simian malaria. The aim of the study is to provide an accurate molecular method for identifying the four [...] Read more.

The Leucosphyrus Group of mosquitoes are the major simian malaria vectors in Malaysia. Accurate species identification is required to help in curbing the spread of simian malaria. The aim of the study is to provide an accurate molecular method for identifying the four important Anopheles vector species found in Malaysia. Mosquito specimens were collected from various localities in Malaysia, where simian malaria cases were reported. DNA from 122 mosquito specimens was tested to develop a multiplex polymerase chain reaction (PCR) assay. The specificity of this assay was tested against other mosquito species. Molecular identification of the species was further confirmed by analysing the internal transcribed spacer 2 (ITS2) DNA region of the specimens. Anopheles balabacensis and An. latens showed two distinct clades in the phylogenetic tree. The multiplex PCR assay was developed based on the ITS2 region for the identification of Anopheles introlatus (298–299 bp), Anopheles latens (197–198 bp), Anopheles cracens (421–426 bp), and Anopheles balabacensis (224–228 bp). This method will be useful to accurately identify the major Anopheles Leucosphyrus Group species in Malaysia, which are difficult to identify morphologically, to determine the correct vector as well as its geographical distribution. Full article

(This article belongs to the Special Issue Vector-Borne Diseases in a Changing World)

► Show Figures

Figure 1

15 pages, 1665 KB

Open AccessArticle

Nematodes in the Pine Forests of Northern and Central Greece

by Maria Karmezi, Alkmini Bataka, Dimitrios Papachristos and Dimitrios N. Avtzis

Insects 2022, 13(2), 194; https://doi.org/10.3390/insects13020194 - 13 Feb 2022

Cited by 11 | Viewed by 3688

Abstract

In the context of plants or plant products protection by harmful organisms, measures have been taken by EU countries in order to prevent their introduction and establishment into the EU, and also limit their expansion in case they do enter. Such a case [...] Read more.

In the context of plants or plant products protection by harmful organisms, measures have been taken by EU countries in order to prevent their introduction and establishment into the EU, and also limit their expansion in case they do enter. Such a case is Bursaphelenchus xylophilus (Parasitaphelenchidae, Nematoda), already recorded in Portugal and Spain. So, Member States should take all the appropriate steps in order to monitor and confine if necessary susceptible plants and/or plant products. Such measures include annual surveys even in countries where pine wilt disease does not occur yet. Therefore, national survey programs are widely established, sampling and examining samples from pine trees showing suspicious symptoms that could potentially be attributed to B. xylophilus. In this direction, such a network has also been established in Greece collecting and examining wood samples nationwide. In total, 123 wood samples were collected from conifer trees of Northern and Central Greece. Though B. xylophilus was absent from all samples examined, four other Bursaphelenchus species were identified. In addition, other nematode taxa were also recorded, including several phytophagous, microbivorous as well as predatory nematode species. This highlights the fact that besides preventing the introduction of B. xylophilus in Greece, national survey programs can significantly contribute to and enhance our knowledge of the indigenous nematode species. Full article

(This article belongs to the Special Issue Selected Papers from the 1st International Electronic Conference on Entomology)

► Show Figures

Figure 1

13 pages, 2044 KB

Open AccessArticle

¹H NMR Profiling of Honey Bee Bodies Revealed Metabolic Differences between Summer and Winter Bees

by Saetbyeol Lee, Filip Kalcic, Iola F. Duarte, Dalibor Titera, Martin Kamler, Pavel Mrna, Pavel Hyrsl, Jiri Danihlik, Pavel Dobes, Martin Kunc, Anna Pudlo and Jaroslav Havlik

Insects 2022, 13(2), 193; https://doi.org/10.3390/insects13020193 - 12 Feb 2022

Cited by 11 | Viewed by 6157

Abstract

In temperate climates, honey bee workers of the species Apis mellifera have different lifespans depending on the seasonal phenotype: summer bees (short lifespan) and winter bees (long lifespan). Many studies have revealed the biochemical parameters involved in the lifespan differentiation of summer and [...] Read more.

In temperate climates, honey bee workers of the species Apis mellifera have different lifespans depending on the seasonal phenotype: summer bees (short lifespan) and winter bees (long lifespan). Many studies have revealed the biochemical parameters involved in the lifespan differentiation of summer and winter bees. However, comprehensive information regarding the metabolic changes occurring in their bodies between the two is limited. This study used proton nuclear magnetic resonance (¹H NMR) spectroscopy to analyze the metabolic differences between summer and winter bees of the same age. The multivariate analysis showed that summer and winter bees could be distinguished based on their metabolic profiles. Among the 36 metabolites found, 28 metabolites have displayed significant changes from summer to winter bees. Compared to summer bees, trehalose in winter bees showed 1.9 times higher concentration, and all amino acids except for proline and alanine showed decreased patterns. We have also detected an unknown compound, with a CH₃ singlet at 2.83 ppm, which is a potential biomarker that is about 13 times higher in summer bees. Our results show that the metabolites in summer and winter bees have distinctive characteristics; this information could provide new insights and support further studies on honey bee longevity and overwintering. Full article

(This article belongs to the Section Social Insects and Apiculture)

► Show Figures

Figure 1

10 pages, 452 KB

Open AccessArticle

Organophosphate Insecticides Resistance in Field Populations of House Flies, Musca domestica L.: Levels of Resistance and Acetylcholinesterase Activity

by Yasser Abobakr, Faisal I. Al-Hussein, Alaa E. Bayoumi, Ali A. Alzabib and Ali S. Al-Sarar

Insects 2022, 13(2), 192; https://doi.org/10.3390/insects13020192 - 11 Feb 2022

Cited by 12 | Viewed by 4181

Abstract

The house fly, Musca domestica L., is an important medical and veterinary pest associated with humans and livestock. Management of house flies has relied extensively on chemical control. In this study, we report on the resistance of house fly field-collected populations to diazinon [...] Read more.

The house fly, Musca domestica L., is an important medical and veterinary pest associated with humans and livestock. Management of house flies has relied extensively on chemical control. In this study, we report on the resistance of house fly field-collected populations to diazinon and fenitrothion OP insecticides in Riyadh, Saudi Arabia. The diazinon and fenitrothion median lethal dose (LD₅₀) values against adult female M. domestica field-collected populations were significantly higher than those of the laboratory (LAB) strain. Different levels of resistance were detected in all field-collected populations toward the two OP insecticides. The resistance ratios for diazinon ranged from 62.47 to 309.78, while there were 53.08 to 261.24 for fenitrothion in the eight field-collected populations. The specific activity of acetylcholinesterase (AChE) in all field populations was significantly (p < 0.05) higher than that in the LAB strain. In vitro diazinon and fenitrothion median inhibitory concentration (IC₅₀) values of LAB strain AChE activity were significantly (p < 0.05) lower than those for field-collected populations. This study found high levels of resistance in the house fly field-collected populations to diazinon and fenitrothion. Replacing these two insecticides and any other OPs with novel ones that have different modes of action is an urgent need in the insect-vector control programs in Riyadh, Saudi Arabia. An altered AChE enzyme of M. domestica field populations might be partially responsible for the developed resistance. Monitoring of insecticide resistance development in M. domestica populations and a better understanding of its mechanisms are needed to design operative management strategies for controlling the house flies. Full article

► Show Figures

Graphical abstract

13 pages, 1705 KB

Open AccessArticle

Invasive Populations of the Emerald Ash Borer Agrilus planipennis Fairmaire, 1888 (Coleoptera: Buprestidae) in Saint Petersburg, Russia: A Hitchhiker?

by Andrey V. Selikhovkin, Dmitry L. Musolin, Boris G. Popovichev, Sergey A. Merkuryev, Mark G. Volkovitsh and Rimvys Vasaitis

Insects 2022, 13(2), 191; https://doi.org/10.3390/insects13020191 - 11 Feb 2022

Cited by 13 | Viewed by 5508

Abstract

The emerald ash borer (EAB), Agrilus planipennis, is an invasive beetle of East Asian origin that has killed millions of ash trees (Fraxinus spp.) in North America and Russia. In September 2020, EAB was detected in Saint Petersburg, a notable event [...] Read more.

The emerald ash borer (EAB), Agrilus planipennis, is an invasive beetle of East Asian origin that has killed millions of ash trees (Fraxinus spp.) in North America and Russia. In September 2020, EAB was detected in Saint Petersburg, a notable event for the metropolitan city. The aim of the present study was to investigate the occurrence and ecology of EAB in Saint Petersburg. The presence of two distinct enclave populations of EAB was revealed, each of which has, most likely, been established through separate events of “hitchhiking” via transport vehicles. Following the invasion, the further spread of EAB in Saint Petersburg was slow and locally restricted, most likely due to climatic factors. This spread by “hitchhiking” suggests that the possibility of the further long-distance geographic spread of EAB in the Baltic Sea region (the EU) is high, both by ground transport (120–130 km distance from EU borders) and ferries that transport cars across the Baltic Sea. In certain cases, the development of EAB on Fraxinus excelsior, based on the stem portion colonized, larval densities, number of galleries, exit holes, viable larvae, and emerged adult beetles, was more successful than in Fraxinus pennsylvanica trees. The observed relatively high sensitivity of F. excelsior to EAB, therefore, casts doubt on the efficacy and benefits of the currently ongoing selection and breeding projects against ash dieback (ADB) disease, which is caused by the fungus Hymenoscyphus fraxineus. Inventory, mapping, and monitoring of surviving F. excelsior trees infested by both ADB and EAB are necessary to acquire genetic resources for work on the strategic long-term restoration of F. excelsior, tackling the probable invasion of EAB to the EU. Full article

► Show Figures

Figure 1

14 pages, 2160 KB

Open AccessArticle

Illumina Short-Read Sequencing of the Mitogenomes of Novel Scarites subterraneus Isolates Allows for Taxonomic Refinement of the Genus Scarites Fabricius 1775, within the Carabidae Family

by Elliot C. Kyndt and John A. Kyndt

Insects 2022, 13(2), 190; https://doi.org/10.3390/insects13020190 - 11 Feb 2022

Cited by 2 | Viewed by 3812

Abstract

We sequenced the complete mitogenomes, 18S and 28S rRNA of two new Scarites isolates, collected in Eastern Nebraska and Northern Arkansas (US). Based on molecular sequence data comparison and morphological characteristics, the new isolates were identified as a subspecies of Scarites subterraneus Fabricius [...] Read more.

We sequenced the complete mitogenomes, 18S and 28S rRNA of two new Scarites isolates, collected in Eastern Nebraska and Northern Arkansas (US). Based on molecular sequence data comparison and morphological characteristics, the new isolates were identified as a subspecies of Scarites subterraneus Fabricius 1775, for which we propose the subspecies names ‘nebraskensis’ and ‘arkansensis’. The new 18S and 28S rRNA sequences were found to be 99% and 98% identical to Scarites subterraneus. There are no other Scarites 18S or 28S rRNA sequences in the Genbank database, however, phylogenetic analysis of the Cox1 genes showed S. vicinus Chaudoir, 1843, and S. aterrimus Morawitz, 1863, as the closest relatives. This is the first report of a mitogenome for S. subterraneus, and only the second mitogenome for that genus. The nucleotide sequence identity between the mitogenomes of the two isolates is 98.8%, while the earlier sequenced S. buparius Forster 1771 mitogenome is more distantly related, with only 90% (to ssp. nebraskensis) and 89% (to ssp. arkansensis) overall nucleotide sequence identity. These new mitogenomes, and their phylogenetic analysis, firmly establish the position of Scarites on the Carabidae family tree and further refine the genus. In addition to the molecular data provided for the Scarites species, this approach also allowed us to identify bacterial and viral signatures for Providencia, Myroides, Spiroplasma, and a giant Nucleocytoviricota virus, associated with the Scarites species. We hereby present a simple and efficient protocol for identification and phylogenetic analysis of Scarites, that is applicable to other Coleoptera, based on total DNA extraction and Illumina short-read Next-Gen sequencing. Full article

(This article belongs to the Section Insect Molecular Biology and Genomics)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Insects, Volume 13, Issue 2 (February 2022) – 114 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI