Insects

12 pages, 582 KiB

Open AccessArticle

Oxidative Stress Response of Honey Bee Colonies (Apis mellifera L.) during Long-Term Exposure at a Frequency of 900 MHz under Field Conditions

by Marinko Vilić, Ivona Žura Žaja, Mirta Tkalec, Perica Tucak, Krešimir Malarić, Nato Popara, Nikolino Žura, Selim Pašić and Ivana Tlak Gajger

Insects 2024, 15(5), 372; https://doi.org/10.3390/insects15050372 - 20 May 2024

Viewed by 2694

Abstract

In this study, oxidative stress and lipid peroxidation in honey bee larvae, pupae and the midguts of adult bees were investigated during a one-year exposure to radiofrequency electromagnetic fields (RF-EMFs) at a frequency of 900 MHz under field conditions. The experiment was carried [...] Read more.

In this study, oxidative stress and lipid peroxidation in honey bee larvae, pupae and the midguts of adult bees were investigated during a one-year exposure to radiofrequency electromagnetic fields (RF-EMFs) at a frequency of 900 MHz under field conditions. The experiment was carried out on honey bee colonies at three locations with electric field levels of 30 mV m⁻¹, 70 mV m⁻¹ and 1000 mV m⁻¹. Antioxidant enzymes, glutathione-S-transferase (GST), catalase (CAT) and superoxide dismutase (SOD) and thiobarbituric acid reactive substances (TBARS) as indicators of lipid peroxidation were measured spectrophotometrically. The GST activity within the same developmental stage showed no significant differences regardless of electric field level or sampling time. The highest GST activity was found in the pupae, followed by activity in the larvae and midguts. Both CAT activity and TBARS concentration were the highest in the midguts, regardless of field level and sampling time. The larvae showed a significantly higher TBARS concentration at the location with an electric field level of 1000 mV m⁻¹ compared to the locations with lower levels. Our results show that RF-EMFs at a frequency of 900 MHz can cause oxidative stress in honey bees, with the larval stage being more sensitive than the pupal stage, but there was no linear relationship between electric field level and effect in any of the developmental stages. Full article

(This article belongs to the Collection Impact of Environmental Factors and Management Practices on Bee Health)

► Show Figures

Figure 1

15 pages, 3867 KiB

Open AccessArticle

A New Species of Scymnus (Coleoptera, Coccinellidae) from Pakistan with Mitochondrial Genome and Its Phylogenetic Implications

by Zafar Iqbal, Rashid Azad, Xiao-Sheng Chen, Xiao-Ling Lin, Zichen Zhou, Xing-Min Wang and Rui-E Nie

Insects 2024, 15(5), 371; https://doi.org/10.3390/insects15050371 - 19 May 2024

Viewed by 1320

Abstract

In this study, a new species of the subgenus Pullus belonging to the Scymnus genus from Pakistan, Scymnus (Pullus) cardi sp. nov., was described and illustrated, with information on its distribution, host plants, and prey. Additionally, the completed mitochondrial genome (mitogenome) of the [...] Read more.

In this study, a new species of the subgenus Pullus belonging to the Scymnus genus from Pakistan, Scymnus (Pullus) cardi sp. nov., was described and illustrated, with information on its distribution, host plants, and prey. Additionally, the completed mitochondrial genome (mitogenome) of the new species using high-throughput sequencing technology was obtained. The genome contains the typical 37 genes (13 protein-coding genes, two ribosomal RNAs, and 22 transfer RNAs) and a non-coding control region, and is arranged in the same order as that of the putative ancestor of beetles. The AT content of the mitogenome is approximately 85.1%, with AT skew and GC skew of 0.05 and −0.43, respectively. The calculated values of relative synonymous codon usage (RSCU) determine that the codon UUA (L) has the highest frequency. Furthermore, we explored the phylogenetic relationship among 59 representatives of the Coccinellidae using Bayesian inference and maximum likelihood methods, the results of which strongly support the monophyly of Coccinellinae. The phylogenetic results positioned Scymnus (Pullus) cardi in a well-supported clade with Scymnus (Pullus) loewii and Scymnus (Pullus) rubricaudus within the genus Scymnus and the tribe Scymnini. The mitochondrial sequence of S. (P.) cardi will contribute to the mitochondrial genome database and provide helpful information for the identification and phylogeny of Coccinellidae. Full article

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

► Show Figures

Figure 1

13 pages, 3866 KiB

Open AccessReview

Biosynthesis of Pteridines in Insects: A Review

by Juan Ferré

Insects 2024, 15(5), 370; https://doi.org/10.3390/insects15050370 - 19 May 2024

Cited by 1 | Viewed by 1461

Abstract

Pteridines are important cofactors for many biological functions of all living organisms, and they were first discovered as pigments of insects, mainly in butterfly wings and the eye and body colors of insects. Most of the information on their structures and biosynthesis has [...] Read more.

Pteridines are important cofactors for many biological functions of all living organisms, and they were first discovered as pigments of insects, mainly in butterfly wings and the eye and body colors of insects. Most of the information on their structures and biosynthesis has been obtained from studies with the model insects Drosophila melanogaster and the silkworm Bombyx mori. This review discusses, and integrates into one metabolic pathway, the different branches which lead to the synthesis of the red pigments “drosopterins”, the yellow pigments sepiapterin and sepialumazine, the orange pigment erythropterin and its related yellow metabolites (xanthopterin and 7-methyl-xanthopterin), the colorless compounds with violet fluorescence (isoxanthopterin and isoxantholumazine), and the branch leading to tetrahydrobiopterin, the essential cofactor for the synthesis of aromatic amino acids and biogenic amines. Full article

► Show Figures

Graphical abstract

14 pages, 881 KiB

Open AccessReview

Engineering Gut Symbionts: A Way to Promote Bee Growth?

by Pachara Sattayawat, Sahutchai Inwongwan, Nuttapol Noirungsee, Jilian Li, Jun Guo and Terd Disayathanoowat

Insects 2024, 15(5), 369; https://doi.org/10.3390/insects15050369 - 19 May 2024

Cited by 1 | Viewed by 1774

Abstract

Bees play a crucial role as pollinators, contributing significantly to ecosystems. However, the honeybee population faces challenges such as global warming, pesticide use, and pathogenic microorganisms. Promoting bee growth using several approaches is therefore crucial for maintaining their roles. To this end, the [...] Read more.

Bees play a crucial role as pollinators, contributing significantly to ecosystems. However, the honeybee population faces challenges such as global warming, pesticide use, and pathogenic microorganisms. Promoting bee growth using several approaches is therefore crucial for maintaining their roles. To this end, the bacterial microbiota is well-known for its native role in supporting bee growth in several respects. Maximizing the capabilities of these microorganisms holds the theoretical potential to promote the growth of bees. Recent advancements have made it feasible to achieve this enhancement through the application of genetic engineering. In this review, we present the roles of gut symbionts in promoting bee growth and collectively summarize the engineering approaches that would be needed for future applications. Particularly, as the engineering of bee gut symbionts has not been advanced, the dominant gut symbiotic bacteria Snodgrassella alvi and Gilliamella apicola are the main focus of the paper, along with other dominant species. Moreover, we propose engineering strategies that will allow for the improvement in bee growth with listed gene targets for modification to further encourage the use of engineered gut symbionts to promote bee growth. Full article

(This article belongs to the Special Issue Breakthrough Technologies for Future Entomology)

► Show Figures

Figure 1

12 pages, 1267 KiB

Open AccessArticle

Less Known Is More Feared—A Survey of Children’s Knowledge of and Attitudes towards Honeybees

by Emmanuele Leto, Francesco Pace, Giulia Sciotto and Barbara Manachini

Insects 2024, 15(5), 368; https://doi.org/10.3390/insects15050368 - 18 May 2024

Viewed by 1259

Abstract

The global decline in the number of pollinators has elicited considerable public attention. To the general public, honeybees are considered to be the primary pollinators. Also, a decline in managed honeybee stocks is alarming and could lead to declining pollination services and reduced [...] Read more.

The global decline in the number of pollinators has elicited considerable public attention. To the general public, honeybees are considered to be the primary pollinators. Also, a decline in managed honeybee stocks is alarming and could lead to declining pollination services and reduced ecosystem biodiversity, although the Apis mellifera is the least likely pollinator species on the planet to be at risk of extinction. A less-than-complete understanding of honeybees and their ecology may hinder their conservation. Ascertaining the public’s level of knowledge about, and perception of, a problem can help in solving it. This research focused mainly on honeybees because people are unlikely to be able to recognize the different species of Apoidea. Schools are ideal places for understanding the basic knowledge and attitudes regarding this insect. We aimed to understand the perception and knowledge of 12–14-year-old children towards honeybees as well as to verify the existence of a correlation between knowledge level and positive perception. Secondary school students can play a key role in the conservation of biodiversity as they are carriers of knowledge in families and will be future citizens. To this end, 231 students were given a 26-item questionnaire related to their perception and knowledge of honeybees. Results indicate that the students have a good understanding of the role that bees play in nature but do not have a completely clear idea of this insect’s interactions with the environment. Results also show that the children feel a certain fear of honeybees, although they respect them. The average score of the ecological branch test exceeded the average score of the perceptual one, indicating that the subjects had a more positive education than perception. Full article

(This article belongs to the Collection Cultural Entomology: Our Love-hate Relationship with Insects)

► Show Figures

Figure 1

14 pages, 3296 KiB

Open AccessArticle

Behavioral and Transcriptomic Analyses in the Indoxacarb Response of a Non-Target Damselfly Species

by Bin Jiang, Wei Wang, Yu Yao, Haobo Zhang, Yongmei Zhang and Yang Sun

Insects 2024, 15(5), 367; https://doi.org/10.3390/insects15050367 - 18 May 2024

Cited by 1 | Viewed by 1157

Abstract

Ischnura senegalensis, which widely spreads in paddy fields, has the potential to be used as a natural predator of insect pests. However, the application of insecticides in the field could pose a threat to the survival of I. senegalensis. Among these [...] Read more.

Ischnura senegalensis, which widely spreads in paddy fields, has the potential to be used as a natural predator of insect pests. However, the application of insecticides in the field could pose a threat to the survival of I. senegalensis. Among these pesticides, indoxacarb, an oxadiazine insecticide, is renowned for its broad-spectrum efficacy against numerous insect pests. In this study, we examined the toxicity of indoxacarb towards the larvae of I. senegalensis. Behavioral experiments and transcriptome analyses were conducted under indoxacarb treatments. Results revealed that indoxacarb induced abnormal body gestures and significant locomotory impairments, which could ultimately reduce the survival rate of the larvae in their natural habitat. Moreover, transcriptome analyses indicated that genes related to muscle function were significantly affected. Interestingly, at lower concentrations of indoxacarb (0.004 mg/L), the larvae seem to detoxify the indoxacarb with the aid of the cytochrome P450 gene. However, under higher concentrations (0.4 mg/L), the sensory abilities of the larvae were significantly diminished, and they were unable to degrade the toxicity of indoxacarb. Our study underscores the importance of carefully evaluating the impact of insecticides on non-target predatory insects before their widespread application. Full article

(This article belongs to the Special Issue Research in Chemical Ecology of Insects of Significance to Forestry and Agriculture)

► Show Figures

Figure 1

15 pages, 4977 KiB

Open AccessArticle

Spatiotemporal Characterization of Dengue Incidence and Its Correlation to Climate Parameters in Indonesia

by Mamenun, Yonny Koesmaryono, Ardhasena Sopaheluwakan, Rini Hidayati, Bambang Dwi Dasanto and Rita Aryati

Insects 2024, 15(5), 366; https://doi.org/10.3390/insects15050366 - 17 May 2024

Cited by 1 | Viewed by 1581

Abstract

Dengue has become a public health concern in Indonesia since it was first found in 1968. This study aims to determine dengue hotspot areas and analyze the spatiotemporal distribution of dengue and its association with dominant climate parameters nationally. Monthly data for dengue [...] Read more.

Dengue has become a public health concern in Indonesia since it was first found in 1968. This study aims to determine dengue hotspot areas and analyze the spatiotemporal distribution of dengue and its association with dominant climate parameters nationally. Monthly data for dengue and climate observations (i.e., rainfall, relative humidity, average, maximum, and minimum temperature) at the regency/city level were utilized. Dengue hotspot areas were determined through K-means clustering, while Singular Value Decomposition (SVD) determined dominant climate parameters and their spatiotemporal distribution. Results revealed four clusters: Cluster 1 comprised cities with medium to high Incidence Rates (IR) and high Case Densities (CD) in a narrow area. Cluster 2 has a high IR and low CD, and clusters 3 and 4 featured medium and low IR and CD, respectively. SVD analysis indicated that relative humidity and rainfall were the most influential parameters on IR across all clusters. Temporal fluctuations in the first mode of IR and climate parameters were clearly delineated. The spatial distribution of heterogeneous correlation between the first mode of rainfall and relative humidity to IR exhibited higher values, which were predominantly observed in Java, Bali, Nusa Tenggara, the eastern part of Sumatra, the southern part of Kalimantan, and several locations in Sulawesi. Full article

(This article belongs to the Special Issue Control and Surveillance of Mosquitoes to Reduce the Spread of Mosquito-Borne Disease)

► Show Figures

Figure 1

14 pages, 1659 KiB

Open AccessArticle

Determination of Triacylglycerol Composition in Mealworm Oil (Tenebrio molitor) via Electrospray Ionization Tandem Mass Spectrometry with Multiple Neutral Loss Scans

by Seongeung Lee, Minkyoung Kim, Hyeokjun Cho and Gyeong-Hwen Lee

Insects 2024, 15(5), 365; https://doi.org/10.3390/insects15050365 - 17 May 2024

Viewed by 1171

Abstract

Mealworms (Tenebrio molitor) have been used as an alternative source of proteins and lipids. Triacylglycerols (TAGs) are major sources of energy and have been used to provide essential fatty acids. They are also the main components of mealworm oil, and their [...] Read more.

Mealworms (Tenebrio molitor) have been used as an alternative source of proteins and lipids. Triacylglycerols (TAGs) are major sources of energy and have been used to provide essential fatty acids. They are also the main components of mealworm oil, and their composition and content are extensively linked to its physical and chemical properties. However, because of the complexity of TAG molecules, their identification and quantitation are challenging. This study employed electrospray ionization tandem mass spectrometry (ESI-MS/MS) with multiple neutral loss scans (NLS) to analyze the TAG composition and content in mealworm oil. Identifying and quantifying TAGs using ESI-MS/MS in combination with multiple NLS was an efficient way to improve accuracy and timeliness. For the accurate quantification of TAGs, isotopic deconvolution and correlation factors were applied. A total of 57 TAGs were identified and quantified: C52:2 (16:0/18:1/18:1) (1549.4 nmol/g, 18.20%), C52:3 (16:0/18:1/18:2) (1488.1 nmol/g, 17.48%), C54:4 (18:1/18:1/18:2) (870.1 nmol/g, 10.23%), C54:6 (18:1/18:2/18:2) (659.8 nmol/g, 7.76%) and C52:4 (16:0/18:2/18:2) (600.5 nmol/g, 7.06%), which were the most abundant TAGs present in the mealworm oil. The fundamental properties of mealworm oil, including its degree of oxidation, nutritional effect and physical properties, were elucidated. Full article

(This article belongs to the Topic Edible Insects as Feed and Food: Opportunities and Challenges)

► Show Figures

Figure 1

9 pages, 836 KiB

Open AccessCommunication

Mosquito Egg Raft Distribution Is Affected by Semiochemicals: Indication of Interspecific Competition

by Nimrod Shteindel, Yoram Gerchman and Alon Silberbush

Insects 2024, 15(5), 364; https://doi.org/10.3390/insects15050364 - 16 May 2024

Viewed by 1113

Abstract

Numerous species of animals alter their behavior in response to increasing competition. To do so, they must possess the ability to detect the presence and density of interspecific competitors. We studied the role of semiochemicals released by increasing densities of larval Culiseta longiareolata [...] Read more.

Numerous species of animals alter their behavior in response to increasing competition. To do so, they must possess the ability to detect the presence and density of interspecific competitors. We studied the role of semiochemicals released by increasing densities of larval Culiseta longiareolata Macquart on female oviposition habitat selection in two field experiments. Similarly to C. longiareolata larvae, subordinate Culex laticinctus Edwards are periphyton grazers who dwell in rain-filled pools in the Mediterranean region. We show that C. laticinctus females oviposited significantly less in mesocosm pools that were treated with crowding signals originating from C. longiareolata larvae. In the second experiment, we placed a similar number of larvae directly inside the 50 L mesocosms. These low-density mesocosms did not affect C. laticinctus oviposition but were attractive to conspecific oviposition. These results increase our understanding of the female ability to detect species-specific signals, indicating increased larval competition. Full article

(This article belongs to the Section Insect Behavior and Pathology)

► Show Figures

Figure 1

11 pages, 861 KiB

Open AccessArticle

The Combination of Citrus Rootstock and Scion Cultivar Influences Trioza erytreae (Hemiptera: Triozidae) Survival, Preference Choice and Oviposition

by María Quintana-González de Chaves, Nancy Montero-Gomez, Carlos Álvarez-Acosta, Estrella Hernández-Suárez, Aurea Hervalejo, Juan M. Arjona-López and Francisco J. Arenas-Arenas

Insects 2024, 15(5), 363; https://doi.org/10.3390/insects15050363 - 16 May 2024

Viewed by 1105

Abstract

Trioza erytreae (Del Guercio, 1918) (Hemiptera: Triozidae) is a citrus pest which produces gall symptoms on leaves and transmits bacteria associated with the citrus disease Huanglongbing, ‘Candidatus Liberibacter’ spp. In the present work, the biology and behaviour of T. erytreae were studied [...] Read more.

Trioza erytreae (Del Guercio, 1918) (Hemiptera: Triozidae) is a citrus pest which produces gall symptoms on leaves and transmits bacteria associated with the citrus disease Huanglongbing, ‘Candidatus Liberibacter’ spp. In the present work, the biology and behaviour of T. erytreae were studied in different rootstock–cultivar combinations. Six rootstocks were used, Flying dragon (FD), ‘Cleopatra’ mandarin (CL), Carrizo citrange (CC), Forner-Alcaide no.5 (FA5), Forner-Alcaide no.517 (FA517) and Citrus macrophylla (CM), and six scion cultivars: ‘Star Ruby’, ‘Clemenules’, ‘Navelina’, ‘Valencia Late’, ‘Fino 49’ and ‘Ortanique’. Survival and oviposition were evaluated in a no-choice trial, and preference in a choice trial, all of them under greenhouse conditions. Trioza erytreae did not show a clear settle preference for any citrus combination. However, it was able to lay more eggs in ‘Fino 49’ grafted on CC than on FD. In terms of survival, ‘Ortanique’ grafted onto FA5 was more suitable than when grafted onto FA517, and in the case of ‘Valencia Late’, when it was grafted onto CM rather than CC. Our results showed that T. erytreae behave differently depending on the citrus combination. Full article

(This article belongs to the Special Issue Monitoring and Management of Invasive Insect Pests)

► Show Figures

Figure 1

19 pages, 5059 KiB

Open AccessArticle

Unraveling the Role of Cuticular Protein 3-like (HvCP3L) in the Chitin Pathway through RNAi and Methoxyfenozide Stress Response in Heortia vitessoides Moore

by Hanyang Wang, Mingxu Sun, Na Liu, Mingliang Yin and Tong Lin

Insects 2024, 15(5), 362; https://doi.org/10.3390/insects15050362 - 16 May 2024

Cited by 1 | Viewed by 885

Abstract

Cuticle proteins (CPs) constitute a multifunctional family; however, the physiological role of Cuticle Protein 3-like (CP3L) in Heortia vitessoides Moore remains largely unclear. In this study, we cloned the HvCP3L gene from the transcriptional library of Heortia vitessoides Moore. RT-qPCR results revealed that [...] Read more.

Cuticle proteins (CPs) constitute a multifunctional family; however, the physiological role of Cuticle Protein 3-like (CP3L) in Heortia vitessoides Moore remains largely unclear. In this study, we cloned the HvCP3L gene from the transcriptional library of Heortia vitessoides Moore. RT-qPCR results revealed that HvCP3L exhibited high expression levels during the larval stage of Heortia vitessoides Moore, particularly at the L5D1 stage, observed in both larval and adult heads. Through RNA interference, we successfully silenced the HvCP3L gene, resulting in a significant reduction in the survival rate of Heortia vitessoides Moore, with the survival rate from larvae to adults plummeting to a mere 17.7%, accompanied by phenotypic abnormalities. Additionally, we observed that the knockdown of HvCP3L led to the inhibition of genes in the chitin pathway. Following exposure to methoxyfenozide stress, the HvCP3L gene exhibited significant overexpression, coinciding with phenotypic abnormalities. These findings underscore the pivotal role of HvCP3L in the growth and development of Heortia vitessoides Moore. Full article

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

► Show Figures

Figure 1

19 pages, 4286 KiB

Open AccessArticle

Enhancing Honey Bee Health: Evaluating Pollen Substitute Diets in Field and Cage Experiments

by Hyunjee Kim, Olga Frunze, Jeong-Hyeon Lee and Hyung-Wook Kwon

Insects 2024, 15(5), 361; https://doi.org/10.3390/insects15050361 - 16 May 2024

Viewed by 1539

Abstract

Honey bees (Apis mellifera L.) play vital roles as agricultural pollinators and honey producers. However, global colony losses are increasing due to multiple stressors, including malnutrition. Our study evaluated the effects of four pollen substitute diets (Diet 1, Diet 2, Diet 3, [...] Read more.

Honey bees (Apis mellifera L.) play vital roles as agricultural pollinators and honey producers. However, global colony losses are increasing due to multiple stressors, including malnutrition. Our study evaluated the effects of four pollen substitute diets (Diet 1, Diet 2, Diet 3, and Control) through field and cage experiments, analyzing 11 parameters and 21 amino acids. Notably, Diet 1 demonstrated significantly superior performance in the field experiment, including the number of honey bees, brood area, consumption, preference, colony weight, and honey production. In the cage experiment, Diet 1 also showed superior performance in dried head and thorax weight and vitellogenin (vg) gene expression levels. Canonical discriminant and principle component analyses highlighted Diet 1’s distinctiveness, with histidine, diet digestibility, consumption, vg gene expression levels, and isoleucine identified as key factors. Arginine showed significant correlations with a wide range of parameters, including the number of honey bees, brood area, and consumption, with Diet 1 exhibiting higher levels. Diet 1, containing apple juice, soytide, and Chlorella as additive components, outperformed the other diets, suggesting an enhanced formulation for pollen substitute diets. These findings hold promise for the development of more effective diets, potentially contributing to honey bee health. Full article

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

► Show Figures

Graphical abstract

14 pages, 2502 KiB

Open AccessArticle

The Function of Termicin from Odontotermes formosanus (Shiraki) in the Defense against Bacillus thuringiensis (Bt) and Beauveria bassiana (Bb) Infection

by Xiaogang Li, Mingyu Wang, Kai Feng, Hao Sun and Fang Tang

Insects 2024, 15(5), 360; https://doi.org/10.3390/insects15050360 - 16 May 2024

Cited by 1 | Viewed by 1290

Abstract

Odontotermes formosanus (Shiraki) is a subterranean termite species known for causing severe damage to trees and structures such as dams. During the synergistic evolution of O. formosanus with pathogenic bacteria, the termite has developed a robust innate immunity. Termicin is a crucial antimicrobial [...] Read more.

Odontotermes formosanus (Shiraki) is a subterranean termite species known for causing severe damage to trees and structures such as dams. During the synergistic evolution of O. formosanus with pathogenic bacteria, the termite has developed a robust innate immunity. Termicin is a crucial antimicrobial peptide in termites, significantly contributing to the defense against external infections. Building upon the successful construction and expression of the dsRNA-HT115 engineering strains of dsOftermicin1 and dsOftermicin2 in our laboratory, this work employs the ultrasonic breaking method to establish an inactivated dsOftermicins-HT115 technological system capable of producing a substantial quantity of dsRNA. This approach also addresses the limitation of transgenic strains which cannot be directly applied. Treatment of O. formosanus with dsOftermicins produced by this method could enhance the virulence of both Bt and Bb to the termites. This study laid the theoretical groundwork for the development of novel termite immunosuppressants and for the advancement and application of termite biological control strategies. Full article

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

► Show Figures

Graphical abstract

41 pages, 42352 KiB

Open AccessArticle

Revision of the Genus Rhagastis Rothschild & Jordan, 1903 (Lepidoptera: Sphingidae) from China, Based on Morphological and Phylogenetic Analyses

by Zhuo-Heng Jiang, Jia-Xin Wang, Zhen-Bang Xu, Ian J. Kitching, Chia-Lung Huang, Shao-Ji Hu and Yun-Li Xiao

Insects 2024, 15(5), 359; https://doi.org/10.3390/insects15050359 - 15 May 2024

Cited by 1 | Viewed by 1246

Abstract

Here, the taxonomy of the genus Rhagastis Rothschild & Jordan, 1903 (Lepidoptera, Sphingidae, Macroglossinae, Macroglossini) from China is revised based on differences in wing morphology, male and female genitalia, and the phylogenetic relationship of the DNA barcodes. Subspecies of Rhagastis albomarginatus (Rothschild, 1894) and [...] Read more.

Here, the taxonomy of the genus Rhagastis Rothschild & Jordan, 1903 (Lepidoptera, Sphingidae, Macroglossinae, Macroglossini) from China is revised based on differences in wing morphology, male and female genitalia, and the phylogenetic relationship of the DNA barcodes. Subspecies of Rhagastis albomarginatus (Rothschild, 1894) and R. castor (Walker, 1856) are treated as “good” species, namely Rhagastis dichroae Mell, 1922 stat. nov.; R. everetti Rothschild & Jordan, 1903 stat. nov.; R. aurifera (Butler, 1875) stat. rev.; R. chinensis Mell, 1922 stat. nov.; R. formosana Clark, 1925 stat. nov.; and R. jordani Oberthür, 1904 stat. rev. The distribution maps, biological notes, and ecological records of the genus Rhagastis Rothschild & Jordan, 1903 from China are given, and a species inventory of genus Rhagastis in the world is also included. Full article

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

► Show Figures

Figure 1

13 pages, 1671 KiB

Open AccessArticle

Metabolic Resistance and Not Voltage-Gated Sodium Channel Gene Mutation Is Associated with Pyrethroid Resistance of Aedes albopictus (Skuse, 1894) from Cambodia

by Sébastien Marcombe, Bros Doeurk, Phoutmany Thammavong, Tuba Veseli, Christian Heafield, Molly-Ann Mills, Sedra Kako, Marcelly Ferreira Prado, Shakira Thomson, Saffron Millett, Timothy Hill, Imogen Kentsley, Shereena Davies, Geethika Pathiraja, Ben Daniels, Lucianna Browne, Miranda Nyamukanga, Jess Harvey, Lyranne Rubinstein, Chloe Townsend, Zack Allen, Christopher Davey-Spence, Adina Hupi, Andrew K. Jones and Sebastien Boyer Show full author list Hide full author list

Insects 2024, 15(5), 358; https://doi.org/10.3390/insects15050358 - 15 May 2024

Cited by 1 | Viewed by 2012

Abstract

(1) Background: In Cambodia, Aedes albopictus is an important vector of the dengue virus. Vector control using insecticides is a major strategy implemented in managing mosquito-borne diseases. Resistance, however, threatens to undermine the use of insecticides. In this study, we present the levels [...] Read more.

(1) Background: In Cambodia, Aedes albopictus is an important vector of the dengue virus. Vector control using insecticides is a major strategy implemented in managing mosquito-borne diseases. Resistance, however, threatens to undermine the use of insecticides. In this study, we present the levels of insecticide resistance of Ae. albopictus in Cambodia and the mechanisms involved. (2) Methods: Two Ae. albopictus populations were collected from the capital, Phnom Penh city, and from rural Pailin province. Adults were tested with diagnostic doses of malathion (0.8%), deltamethrin (0.03%), permethrin (0.25%), and DDT (4%) using WHO tube assays. Synergist assays using piperonyl butoxide (PBO) were implemented before the pyrethroid assays to detect the potential involvement of metabolic resistance mechanisms. Adult female mosquitoes collected from Phnom Penh and Pailin were tested for voltage-gated sodium channel (VGSC) kdr (knockdown resistance) mutations commonly found in Aedes sp.-resistant populations throughout Asia (S989P, V1016G, and F1534C), as well as for other mutations (V410L, L982W, A1007G, I1011M, T1520I, and D1763Y). (3) Results: The two populations showed resistance against all the insecticides tested (<90% mortality). The use of PBO (an inhibitor of P450s) strongly restored the efficacy of deltamethrin and permethrin against the two resistant populations. Sequences of regions of the vgsc gene showed a lack of kdr mutations known to be associated with pyrethroid resistance. However, four novel non-synonymous mutations (L412P/S, C983S, Q1554STOP, and R1718L) and twenty-nine synonymous mutations were detected. It remains to be determined whether these mutations contribute to pyrethroid resistance. (4) Conclusions: Pyrethroid resistance is occurring in two Ae. albopictus populations originating from urban and rural areas of Cambodia. The resistance is likely due to metabolic resistance specifically involving P450s monooxygenases. The levels of resistance against different insecticide classes are a cause for concern in Cambodia. Alternative tools and insecticides for controlling dengue vectors should be used to minimize disease prevalence in the country. Full article

(This article belongs to the Special Issue Molecular Mechanisms of Insecticide Resistance)

► Show Figures

Graphical abstract

21 pages, 28015 KiB

Open AccessArticle

Comparative Mitogenome of Phylogenetic Relationships and Divergence Time Analysis within Potamanthidae (Insecta: Ephemeroptera)

by Zhi-Qiang Guo, Ya-Jie Gao, Yu-Xin Chen, Le-Mei Zhan, Kenneth B. Storey, Dan-Na Yu and Jia-Yong Zhang

Insects 2024, 15(5), 357; https://doi.org/10.3390/insects15050357 - 15 May 2024

Cited by 1 | Viewed by 1156

Abstract

Potamanthidae belongs to the superfamily Ephemeroidea but has no complete mt genome released in the NCBI (except for two unchecked and one partial mt genome). Since the sister clade to Potamanthidae has always been controversial, we sequenced seven mt genomes of Potamanthidae (two [...] Read more.

Potamanthidae belongs to the superfamily Ephemeroidea but has no complete mt genome released in the NCBI (except for two unchecked and one partial mt genome). Since the sister clade to Potamanthidae has always been controversial, we sequenced seven mt genomes of Potamanthidae (two species from Rhoenanthus and five species from Potamanthus) in order to rebuild the phylogenetic relationships of Potamanthidae in this study. The divergence time of Potamanthidae was also investigated by utilizing five fossil calibration points because of the indeterminate origin time. In addition, because Rhoenanthus coreanus and Potamanthus luteus are always in low-temperature environments, we aimed to explore whether these two species were under positive selection at the mt genome level. Amongst the 13 PCGs, CGA was used as the start codon in COX1, whereas other genes conformed to initiating with an ATN start codon. From this analysis, UUA (L), AUU (I), and UUU (F) had the highest usage. Furthermore, the DHU arm was absent in the secondary structure of S1 in all species. By combining the 13 PCGs and 2 rRNAs, we reconstructed the phylogenetic relationship of Potamanthidae within Ephemeroptera. The monophyly of Potamanthidae and the monophyly of Rhoenanthus and Potamanthus were supported in the results. The phylogenetic relationship of Potamanthidae + (Ephemeridae + Polymitarcyidae) was also recovered with a high prior probability. The divergence times of Potamanthidae were traced to be 90.44 Mya (95% HPD, 62.80–121.74 Mya), and the divergence times of Rhoenanthus and Potamanthus originated at approximately 64.77 Mya (95% HPD, 43.82–88.68 Mya), thus belonging to the late Pliocene Epoch or early Miocene Epoch. In addition, the data indicated that R. coreanus was under negative selection and that ATP8 and ND2 in Potamanthidae had a high evolutionary rate. Full article

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

► Show Figures

Figure 1

27 pages, 3555 KiB

Open AccessArticle

Ecological Groups of Coleoptera (Insecta) as Indicators of Habitat Transformation on Drained and Rewetted Peatlands: A Baseline Study from a Carbon Supersite, Kaliningrad, Russia

by Vitalii Alekseev, Maxim Napreenko and Tatiana Napreenko-Dorokhova

Insects 2024, 15(5), 356; https://doi.org/10.3390/insects15050356 - 15 May 2024

Viewed by 980

Abstract

A total of 281 coleopteran species from 41 families were recorded from different sites of an abandoned cut-over peatland designated as the Carbon Measurement Supersite in Kaliningrad Oblast. This beetle assemblage is considered a baseline (pre-impact) faunal assemblage for further investigations during the [...] Read more.

A total of 281 coleopteran species from 41 families were recorded from different sites of an abandoned cut-over peatland designated as the Carbon Measurement Supersite in Kaliningrad Oblast. This beetle assemblage is considered a baseline (pre-impact) faunal assemblage for further investigations during the ‘before–after’ (BA) or ‘before–after control-impact’ (BACI) study on a peatland that is planned to be rewetted. The spontaneously revegetated peatland has a less specialised beetle assemblage than at an intact raised bog. Tyrphobiontic species are completely absent from the peatland, while some tyrphophiles (5.3% of the total beetle fauna) are still found as remnants of the former raised bog communities. The predominant coenotic coleopteran group is tyrphoneutral generalists from various non-bog habitats (72.9%). The species composition is associated with the vegetation structure of the disturbed peatland (fragmentary Sphagnum cover, lack of open habitats, and widespread birch coppice or tree stand), which does not correspond to that of a typical European raised bog. The sampled coleopteran assemblage is divided into several relative ecological groups, whose composition and peculiarities are discussed separately. Possible responses to the rewetting measurements in different coleopteran groups are predicted and briefly discussed. A complex assemblage of stenotopic peatland-specialised tyrphophiles (15 spp.) and the most abundant tyrphoneutral generalists (31 spp.) were assigned as indicators for the environmental monitoring of peatland development. Full article

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

► Show Figures

Figure 1

19 pages, 2827 KiB

Open AccessArticle

Influence of Vineyard Inter-Row Management on Grapevine Leafhoppers and Their Natural Enemies

by Elena Cargnus, Seyedeh Fatemeh Kiaeian Moosavi, Davide Frizzera, Chiara Floreani, Pietro Zandigiacomo, Giovanni Bigot, Davide Mosetti and Francesco Pavan

Insects 2024, 15(5), 355; https://doi.org/10.3390/insects15050355 - 14 May 2024

Cited by 1 | Viewed by 891

Abstract

Inter-row management in vineyards can influence the abundance of grapevine pests and their natural enemies. In 2013–2015, in a vineyard in northeastern Italy, the influence of two vineyard inter-row management strategies (i.e., alternate mowing, AM, and periodical tillage, PT) on the population dynamics [...] Read more.

Inter-row management in vineyards can influence the abundance of grapevine pests and their natural enemies. In 2013–2015, in a vineyard in northeastern Italy, the influence of two vineyard inter-row management strategies (i.e., alternate mowing, AM, and periodical tillage, PT) on the population dynamics of grapevine leafhoppers Hebata vitis and Zygina rhamni and their natural enemies, the mymarid Anagrus atomus and spiders (Araneae), and other hymenopteran parasitoids, were studied with different survey approaches. The infestations of both leafhoppers were lower in AM than PT due to the reduced leafhopper oviposition and higher nymph mortality in AM. This occurred although leafhopper egg parasitization by A. atomus was greater in PT than AM according to a density-dependent relationship with the leafhopper egg amount. Hymenopteran parasitoids other than A. atomus were the most abundant in AM, probably due to the higher availability of nectar and pollen than in PM. The significantly higher population densities of hunting spiders in AM than PT can be associated with the higher predation of leafhopper nymphs. Therefore, the study demonstrated that the alternate mowing of vineyard inter-rows enhances the abundance of natural enemies, such as spiders and hymenopteran parasitoids, and can contribute to grapevine leafhopper pest control. Full article

(This article belongs to the Special Issue Sustainable Management of Arthropod Pests in Agroecosystems)

► Show Figures

Figure 1

14 pages, 7756 KiB

Open AccessArticle

Molecular Data Confirm Interspecific Limits of Four Alloxysta and One Phaenoglyphis Species of Parasitic Wasps within the Subfamily Charipinae (Cynipoidea: Figitidae)

by Mar Ferrer-Suay, Mariana Bulgarella, George E. Heimpel, Ehsan Rakhshani and Jesús Selfa

Insects 2024, 15(5), 354; https://doi.org/10.3390/insects15050354 - 14 May 2024

Viewed by 892

Abstract

The hymenopteran subfamily Charipinae (Cynipoidea: Figitidae) consist of a group of parasitic wasps that are exclusive hyperparasitoids of Hemipteran. The species boundaries in Charipinae have historically been unclear. While diagnostic morphological features have been established for the stepwise separation of species, it is [...] Read more.

The hymenopteran subfamily Charipinae (Cynipoidea: Figitidae) consist of a group of parasitic wasps that are exclusive hyperparasitoids of Hemipteran. The species boundaries in Charipinae have historically been unclear. While diagnostic morphological features have been established for the stepwise separation of species, it is recommended to confirm those limits using molecular data. Here, we focus on the genera Alloxysta Förster, 1869 and Phaenoglyphis Förster, 1869, both of which contain species that are hyperparasitoids of aphids. We sequenced three genes (mitochondrial COI and 16S rDNA, and nuclear ITS2 rDNA) from specimens that were identified as belonging to five species: Alloxysta brevis (Thomson, 1862), A. castanea (Hartig, 1841), A. ramulifera (Thomson, 1862), A. victrix (Westwood, 1833), and Phaenoglyphis villosa (Hartig, 1841). The phylogeny resulting from concatenating these genes supported the species status of the five morphologically identified taxa, with P. villosa nested within Alloxysta. Our study thus indicates that these molecular markers can successfully distinguish charipine species, and also indicates that the genera Alloxysta and Phaenoglyphis may be more closely related than previously hypothesized. We also present the first estimates of genetic distances for these species. Future studies that include more species, loci, and/or genomic data will complement our research and help determine species relationships within the Charipinae subfamily. Full article

(This article belongs to the Collection Hymenoptera: Biology, Taxonomy and Integrated Management)

► Show Figures

Figure 1

20 pages, 737 KiB

Open AccessReview

Mosquitoes (Diptera: Culicidae) of Poland: An Update of Species Diversity and Current Challenges

by Piotr Jawień, Wolf Peter Pfitzner, Francis Schaffner and Dorota Kiewra

Insects 2024, 15(5), 353; https://doi.org/10.3390/insects15050353 - 14 May 2024

Cited by 1 | Viewed by 1822

Abstract

This article presents the current state of knowledge of mosquito species (Diptera: Culicidae) occurring in Poland. In comparison to the most recently published checklists (1999 and 2007), which listed 47 mosquito species, four species (Aedes japonicus, Anopheles daciae, Anopheles hyrcanus [...] Read more.

This article presents the current state of knowledge of mosquito species (Diptera: Culicidae) occurring in Poland. In comparison to the most recently published checklists (1999 and 2007), which listed 47 mosquito species, four species (Aedes japonicus, Anopheles daciae, Anopheles hyrcanus, and Anopheles petragnani) are added to the Polish fauna. Our new checklist of Polish mosquito fauna includes 51 species of mosquitoes from five genera: Aedes (30), Anopheles (8), Coquillettidia (1), Culiseta (7), and Culex (5). Aspects of the ecology and biology of the Polish mosquito fauna, with particular emphasis on newly recorded species, are discussed. Full article

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

► Show Figures

Graphical abstract

16 pages, 2526 KiB

Open AccessArticle

Transcriptomic Insights into Host Metabolism and Immunity Changes after Parasitization by Leptopilina myrica

by Junwei Zhang, Jieyu Shan, Wenqi Shi, Ting Feng, Yifeng Sheng, Zixuan Xu, Zhi Dong, Jianhua Huang and Jiani Chen

Insects 2024, 15(5), 352; https://doi.org/10.3390/insects15050352 - 14 May 2024

Viewed by 1055

Abstract

Parasitoids commonly manipulate their host’s metabolism and immunity to facilitate their offspring survival, but the mechanisms remain poorly understood. Here, we deconstructed the manipulation strategy of a newly discovered parasitoid wasp, L. myrica, which parasitizes D. melanogaster. Using RNA-seq, we analyzed [...] Read more.

Parasitoids commonly manipulate their host’s metabolism and immunity to facilitate their offspring survival, but the mechanisms remain poorly understood. Here, we deconstructed the manipulation strategy of a newly discovered parasitoid wasp, L. myrica, which parasitizes D. melanogaster. Using RNA-seq, we analyzed transcriptomes of L. myrica-parasitized and non-parasitized Drosophila host larvae. A total of 22.29 Gb and 23.85 Gb of clean reads were obtained from the two samples, respectively, and differential expression analysis identified 445 DEGs. Of them, 304 genes were upregulated and 141 genes were downregulated in parasitized hosts compared with non-parasitized larvae. Based on the functional annotations in the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, we found that the genes involved in host nutrition metabolism were significantly upregulated, particularly in carbohydrate, amino acid, and lipid metabolism. We also identified 30 other metabolism-related DEGs, including hexokinase, fatty acid synthase, and UDP-glycosyltransferase (Ugt) genes. We observed that five Bomanin genes (Boms) and six antimicrobial peptides (AMPs) were upregulated. Moreover, a qRT-PCR analysis of 12 randomly selected DEGs confirmed the reproducibility and accuracy of the RNA-seq data. Our results provide a comprehensive transcriptomic analysis of how L. myrica manipulates its host, laying a solid foundation for studies on the regulatory mechanisms employed by parasitoid wasps in their hosts. Full article

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

► Show Figures

Figure 1

11 pages, 2543 KiB

Open AccessArticle

A New Genus of Praeaulacidae (Hymenoptera: Evanioidea) from Mid-Cretaceous Kachin Amber: Insights into a Putative New Praeaulacinae Subclade

by Jingtao Yang, Corentin Jouault, Longfeng Li, Chungkun Shih and Dong Ren

Insects 2024, 15(5), 351; https://doi.org/10.3390/insects15050351 - 13 May 2024

Cited by 1 | Viewed by 1319

Abstract

A new praeaulacid genus and species, Azygdellitha nova gen. et sp. nov., is described and illustrated based on a male specimen from mid-Cretaceous Kachin amber from Hukawng Valley, Myanmar. This newly discovered taxon increased the diversity of praeaulacid wasps during the Cretaceous period. While [...] Read more.

A new praeaulacid genus and species, Azygdellitha nova gen. et sp. nov., is described and illustrated based on a male specimen from mid-Cretaceous Kachin amber from Hukawng Valley, Myanmar. This newly discovered taxon increased the diversity of praeaulacid wasps during the Cretaceous period. While this new taxon shares similarities of wing venation with most species of the subfamily Praeaulacinae, it strongly differs from that of three genera previously described from mid-Cretaceous Kachin amber: Mesevania, Paleosyncrasis, and Praegastrinus. We explore the possibility that these genera constitute a distinct tribe within the Praeaulacinae, distinguished by their wing venation. We provide illustrations and emphasize the potentially diagnostic traits supporting this classification. Full article

(This article belongs to the Collection Hymenoptera: Biology, Taxonomy and Integrated Management)

► Show Figures

Figure 1

16 pages, 2171 KiB

Open AccessArticle

Winter Hive Debris Analysis Is Significant for Assessing the Health Status of Honeybee Colonies (Apis mellifera)

by Ivana Tlak Gajger, Klara Bakarić, Ivan Toplak, Laura Šimenc, Urška Zajc and Metka Pislak Ocepek

Insects 2024, 15(5), 350; https://doi.org/10.3390/insects15050350 - 13 May 2024

Viewed by 1646

Abstract

Honeybee diseases are one of the most significant and most common causes of honeybee colonies’ weakness and death. An early diagnosis of subclinical infections is necessary to implement precautionary and control measures. Sampling debris from hive bottom boards is simple, non-invasive, and cheap. [...] Read more.

Honeybee diseases are one of the most significant and most common causes of honeybee colonies’ weakness and death. An early diagnosis of subclinical infections is necessary to implement precautionary and control measures. Sampling debris from hive bottom boards is simple, non-invasive, and cheap. In this study, we collected winter debris samples in apiaries located in the continental part of Croatia. We used molecular methods, PCR and qPCR, for the first time to analyze those samples. Laboratory results were compared with the health condition and strength of honeybee colonies at an apiary in spring. Our study successfully identified the presence and quantity of various pathogens, including the presence of Vairimorpha spp. (Nosema spp.), quintefied Paenibacillus larvae, Acute Bee Paralysis Virus (ABPV), Black Queen Cell Virus (BQCV), Deformed Wing Virus (DWV), and Sacbrood Virus (SBV). However, our analysis did not detect Melissococcus plutonius, Crithidia mellificae, Lotmaria passim, and Aethina tumida. Samples of winter debris were also examined for the presence and quantification of the V. destructor mites, and their natural mite fall was observed in spring. Honeybee colonies were simultaneously infected by an average of four to six pathogens. Some observed honeybee colonies developed characteristic symptoms, while others did not survive the winter. Full article

(This article belongs to the Special Issue Healthy and Sustainable Beekeeping)

► Show Figures

Figure 1

16 pages, 10525 KiB

Open AccessArticle

Exploring the Dynamic Invasion Pattern of the Black-Headed Fall Webworm in China: Susceptibility to Topography, Vegetation, and Human Activities

by Fan Shao, Jie Pan, Xinquan Ye and Gaosheng Liu

Insects 2024, 15(5), 349; https://doi.org/10.3390/insects15050349 - 13 May 2024

Viewed by 1539

Abstract

The fall webworm (FWW), H. cunea (Drury) (Lepidoptera: Erebidae: Arctiidae), is an extremely high-risk globally invasive pest. Understanding the invasion dynamics of invasive pests and identifying the critical factors that promote their spread is essential for devising practical and efficient strategies for their [...] Read more.

The fall webworm (FWW), H. cunea (Drury) (Lepidoptera: Erebidae: Arctiidae), is an extremely high-risk globally invasive pest. Understanding the invasion dynamics of invasive pests and identifying the critical factors that promote their spread is essential for devising practical and efficient strategies for their control and management. The invasion dynamics of the FWW and its influencing factors were analyzed using standard deviation ellipse and spatial autocorrelation methods. The analysis was based on statistical data on the occurrence of the FWW in China. The dissemination pattern of the FWW between 1979 and 2022 followed a sequence of “invasion-occurrence-transmission-outbreak”, spreading progressively from coastal to inland regions. Furthermore, areas with high nighttime light values, abundant ports, and non-forested areas with low vegetation cover at altitudes below 500 m were more likely to be inhabited by the black-headed FWW. The dynamic invasion pattern and the driving factors associated with the fall webworm (FWW) provide critical insights for future FWW management strategies. These strategies serve not only to regulate the dissemination of insects and diminish migratory tendencies but also to guarantee the implementation of efficient early detection systems and prompt response measures. Full article

(This article belongs to the Special Issue Monitoring and Management of Invasive Insect Pests)

► Show Figures

Figure 1

15 pages, 6514 KiB

Open AccessArticle

Risk Assessment of Spodoptera exempta against Food Security: Estimating the Potential Global Overlapping Areas of Wheat, Maize, and Rice under Climate Change

by Ming Li, Zhenan Jin, Yuhan Qi, Haoxiang Zhao, Nianwan Yang, Jianyang Guo, Baoxiong Chen, Xiaoqing Xian and Wanxue Liu

Insects 2024, 15(5), 348; https://doi.org/10.3390/insects15050348 - 13 May 2024

Viewed by 1397

Abstract

Spodoptera exempta, known as the black armyworm, has been extensively documented as an invasive agricultural pest prevalent across various crop planting regions globally. However, the potential geographical distribution and the threat it poses to host crops of remains unknown at present. Therefore, [...] Read more.

Spodoptera exempta, known as the black armyworm, has been extensively documented as an invasive agricultural pest prevalent across various crop planting regions globally. However, the potential geographical distribution and the threat it poses to host crops of remains unknown at present. Therefore, we used an optimized MaxEnt model based on 841 occurrence records and 19 bioclimatic variables to predict the potential suitable areas of S. exempta under current and future climatic conditions, and the overlap with wheat, rice, and maize planting areas was assessed. The optimized model was highly reliable in predicting potential suitable areas for this pest. The results showed that high-risk distribution areas for S. exempta were mainly in developing countries, including Latin America, central South America, central Africa, and southern Asia. Moreover, for the three major global food crops, S. exempta posed the greatest risk to maize planting areas (510.78 × 10⁴ km²), followed by rice and wheat planting areas. Under future climate scenarios, global warming will limit the distribution of S. exempta. Overall, S. exempta had the strongest effect on global maize production areas and the least on global wheat planting areas. Our study offers a scientific basis for global prevention of S. exempta and protection of agricultural crops. Full article

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

► Show Figures

Figure 1

23 pages, 2375 KiB

Open AccessArticle

Does This Look Infected? Hidden Host Plant Infection by the Pathogen Botrytis cinerea Alters Interactions between Plants, Aphids and Their Natural Enemies in the Field

by Norhayati Ngah, Rebecca L. Thomas and Mark D. E. Fellowes

Insects 2024, 15(5), 347; https://doi.org/10.3390/insects15050347 - 12 May 2024

Cited by 1 | Viewed by 1258

Abstract

Few studies have considered whether hidden (asymptomatic) plant pathogen infection alters ecological interactions at the higher trophic levels, even though such infection still affects plant physiology. We explored this question in two field experiments, where two varieties of lettuce (Little Gem, Tom Thumb) [...] Read more.

Few studies have considered whether hidden (asymptomatic) plant pathogen infection alters ecological interactions at the higher trophic levels, even though such infection still affects plant physiology. We explored this question in two field experiments, where two varieties of lettuce (Little Gem, Tom Thumb) infected with Botrytis cinerea were either (1) naturally colonised by aphids or (2) placed in the field with an established aphid colony. We then recorded plant traits and the numbers and species of aphids, their predators, parasitoids and hyperparasitoids. Infection significantly affected plant quality. In the first experiment, symptomatically infected plants had the fewest aphids and natural enemies of aphids. The diversity and abundance of aphids did not differ between asymptomatically infected and uninfected Little Gem plants, but infection affected the aphid assemblage for Tom Thumb plants. Aphids on asymptomatically infected plants were less attractive to predators and parasitoids than those on uninfected plants, while hyperparasitoids were not affected. In the second experiment, when we excluded natural enemies, aphid numbers were lower on asymptomatically and symptomatically infected plants, but when aphid natural enemies were present, this difference was removed, most likely because aphids on uninfected plants attracted more insect natural enemies. This suggests that hidden pathogen infection may have important consequences for multitrophic interactions. Full article

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

► Show Figures

Figure 1

15 pages, 2935 KiB

Open AccessArticle

Discovery of the Larvae and Pupae of the Black Fly Simulium (Gomphostilbia) khelangense and Breeding Habitats of Potential Pest Species of the S. (G.) chumpornense Subgroup (Simuliidae)

by Isara Thanee, Waraporn Jumpato, Chavanut Jaroenchaiwattanachote, Bhuvadol Gomontean, Wannachai Wannasingha, San Namtaku, Peter H. Adler and Pairot Pramual

Insects 2024, 15(5), 346; https://doi.org/10.3390/insects15050346 - 11 May 2024

Cited by 1 | Viewed by 1284

Abstract

Two species of black flies (Simuliidae) in Thailand, Simulium chumpornense Takaoka and Kuvangkadilok, 2000, and S. khelangense Takaoka, Srisuka & Saeung, 2022, are potent vectors of avian blood protozoa of the genera Leucocytozoon and Trypanosoma and are pests of domestic avian species. Although [...] Read more.

Two species of black flies (Simuliidae) in Thailand, Simulium chumpornense Takaoka and Kuvangkadilok, 2000, and S. khelangense Takaoka, Srisuka & Saeung, 2022, are potent vectors of avian blood protozoa of the genera Leucocytozoon and Trypanosoma and are pests of domestic avian species. Although the adults are abundant throughout Thailand, information on their breeding habitats is limited, and the immature stages of S. khelangense are unknown. We collected the larvae and pupae of S. khelangense from the Mekong River, the first-ever record of Simuliidae from this large continental river. Mitochondrial cytochrome c oxidase I and internal transcribed spacer 2 were used to associate the larvae and pupae with known adults. Both genetic markers strongly supported their identity as S. khelangense. The larvae and pupa of S. khelangense are described. The pupal gill filaments, larval abdominal protuberances, and setae distinguish this species from other members of the S. varicorne species group. The immature stages of S. chumpornense inhabit a wide variety of flowing waters, from small streams (3 m wide) to enormous continental rivers (400 m wide); thus, S. chumpornense is a habitat generalist. In contrast, S. khelangense was found only in the large Mekong River and is, therefore, a habitat specialist. Both species can exploit their principal habitats and produce abundant adult populations. Full article

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

► Show Figures

Figure 1

15 pages, 3018 KiB

Open AccessArticle

Chemical Composition of Essential Oil from Citrus reticulata Blanco cv. Chachiensis (Chachi) and Its Anti-Mosquito Activity against Pyrethroid-Resistant Aedes albopictus

by Jifan Cao, Wende Zheng, Baizhong Chen, Zhenping Yan, Xiaowen Tang, Jiahao Li, Zhen Zhang, Song Ang, Chen Li, Rihui Wu, Panpan Wu and Wen-Hua Chen

Insects 2024, 15(5), 345; https://doi.org/10.3390/insects15050345 - 11 May 2024

Viewed by 1239

Abstract

The overuse of synthetic insecticides has led to various negative consequences, including insecticide resistance, environmental pollution, and harm to public health. This may be ameliorated by using insecticides derived from botanical sources. The primary objective of this study was to evaluate the anti-mosquito [...] Read more.

The overuse of synthetic insecticides has led to various negative consequences, including insecticide resistance, environmental pollution, and harm to public health. This may be ameliorated by using insecticides derived from botanical sources. The primary objective of this study was to evaluate the anti-mosquito activity of the essential oil (EO) of Citrus reticulata Blanco cv. Chachiensis (Chachi) (referred to as CRB) at immature, semi-mature, and mature stages. The chemical compositions of the CRB EO were analyzed using GC-MS. The main components were identified to be D-limonene and γ-terpinene. The contents of D-limonene at the immature, semi-mature, and mature stages were 62.35%, 76.72%, and 73.15%, respectively; the corresponding contents of γ-terpinene were 14.26%, 11.04%, and 11.27%, respectively. In addition, the corresponding contents of a characteristic component, methyl 2-aminobenzoate, were 4.95%, 1.93%, and 2.15%, respectively. CRB EO exhibited significant larvicidal activity against Aedes albopictus (Ae. albopictus, Diptera: Culicidae), with the 50% lethal doses being 65.32, 61.47, and 65.91 mg/L for immature, semi-mature, and mature CRB EO, respectively. CRB EO was able to inhibit acetylcholinesterase and three detoxification enzymes, significantly reduce the diversity of internal microbiota in mosquitoes, and decrease the relative abundance of core species within the microbiota. The present results may provide novel insights into the utilization of plant-derived essential oils in anti-mosquitoes. Full article

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

► Show Figures

Figure 1

12 pages, 1996 KiB

Open AccessArticle

Effects of Artificial Sugar Supplementation on the Composition and Nutritional Potency of Honey from Apis cerana

by Yueyang Hu, Jianhui Liu, Qizhong Pan, Xinxin Shi and Xiaobo Wu

Insects 2024, 15(5), 344; https://doi.org/10.3390/insects15050344 - 10 May 2024

Viewed by 1768

Abstract

In the global apiculture industry, reward feeding and supplementary feeding are essential for maintaining bee colonies. Beekeepers provide artificial supplements to their colonies, typically in the form of either a honey–water solution or sugar syrup. Owing to cost considerations associated with beekeeping, most [...] Read more.

In the global apiculture industry, reward feeding and supplementary feeding are essential for maintaining bee colonies. Beekeepers provide artificial supplements to their colonies, typically in the form of either a honey–water solution or sugar syrup. Owing to cost considerations associated with beekeeping, most beekeepers opt for sugar syrup. However, the effects of different types of artificial sugar supplements on bee colonies and their subsequent impact on honey composition remain unclear. To address this gap, this study compared the chemical composition, antioxidant capacity, and nutritional potency of three types of honey: honey derived from colonies fed sugar syrup (sugar-based product, SP) or a honey–water solution (honey-sourced honey, HH) and naturally sourced honey (flower-sourced honey, FH), which served as the control. The results revealed that FH outperformed HH and SP in terms of total acidity, sugar content, total protein content, and antioxidant capacity, and HH outperformed SP. Regarding nutritional efficacy, including the lifespan and learning and memory capabilities of worker bees, FH exhibited the best outcomes, with no significant differences observed between HH and SP. This study underscores the importance of sugar source selection in influencing honey quality and emphasizes the potential consequences of substituting honey with sugar syrup in traditional apiculture practices. Full article

(This article belongs to the Section Insect Societies and Sociality)

► Show Figures

Figure 1

16 pages, 915 KiB

Open AccessArticle

Effects of Black Soldier Fly (Hermetia illucens L., BSF) Larvae Addition on In Vitro Fermentation Parameters of Goat Diets

by Shengyong Lu, Shengchang Chen, Siwaporn Paengkoum, Nittaya Taethaisong, Weerada Meethip, Jariya Surakhunthod, Qingfeng Wang, Sorasak Thongpea and Pramote Paengkoum

Insects 2024, 15(5), 343; https://doi.org/10.3390/insects15050343 - 10 May 2024

Viewed by 1747

Abstract

The purpose of this experiment was to evaluate the effects of different levels of BSF on rumen in vitro fermentation gas production, methane (CH₄) production, ammonia nitrogen (NH₃-N), and volatile fatty acids (VFAs). The experiment comprised four treatments, each [...] Read more.

The purpose of this experiment was to evaluate the effects of different levels of BSF on rumen in vitro fermentation gas production, methane (CH₄) production, ammonia nitrogen (NH₃-N), and volatile fatty acids (VFAs). The experiment comprised four treatments, each with five replicates. The control group contained no BSF (BSF0), and the treatment groups contained 5% (BSF5), 10% (BSF10), and 15% (BSF15) BSF, respectively. Results showed that at 3 h, 9 h, and 24 h, gas production in BSF5 and BSF10 was significantly higher than in BSF0 and BSF15 (p < 0.05). Gas production in BSF5 and BSF10 was higher than in BSF0, while gas production in BSF15 was lower than in BSF0. At 6 h and 12 h, CH₄ emission in BSF15 was significantly lower than in the other three groups (p < 0.05). There were no differences in the pH of in vitro fermentation after BSF addition (p > 0.05). At 3 h, NH₃-N levels in BSF10 and BSF15 were significantly higher than in BSF0 and BSF5 (p < 0.05). At 6 h, NH₃-N levels in BSF5 and BSF10 were significantly higher than in BSF0 and BSF15 (p < 0.05). Acetic acid, propionic acid, butyric acid, and total VFAs in BSF0, BSF5, and BSF10 were significantly higher than in BSF15 (p < 0.05). In conclusion, gas production, CH₄ emission, NH₃-N, acetic acid, propionic acid, butyric acid, and VFAs were highest in BSF5 and BSF10 and lowest in BSF15. Full article

(This article belongs to the Section Role of Insects in Human Society)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Insects, Volume 15, Issue 5 (May 2024) – 75 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI