Insects

13 pages, 2092 KiB

Open AccessArticle

Transcriptome-Wide Identification of Cytochrome P450s in Tea Black Tussock Moth (Dasychira baibarana) and Candidate Genes Involved in Type-II Sex Pheromone Biosynthesis

by Tiekuang Wang, Xufei Liu, Zongxiu Luo, Xiaoming Cai, Zhaoqun Li, Lei Bian, Chunli Xiu, Zongmao Chen, Qiurong Li and Nanxia Fu

Insects 2024, 15(2), 139; https://doi.org/10.3390/insects15020139 - 19 Feb 2024

Cited by 4 | Viewed by 1574

Abstract

The tea black tussock moth (Dasychira baibarana), a devastating pest in Chinese tea plantations, uses a ternary Type-II pheromone blend containing (3Z,6Z)-cis-9,10-epoxyhenicosa-3,6-diene (Z3,Z6,epo9-21:H), (3Z,6Z,11E)-cis [...] Read more.

The tea black tussock moth (Dasychira baibarana), a devastating pest in Chinese tea plantations, uses a ternary Type-II pheromone blend containing (3Z,6Z)-cis-9,10-epoxyhenicosa-3,6-diene (Z3,Z6,epo9-21:H), (3Z,6Z,11E)-cis-9,10-epoxyhenicosa-3,6,11-triene (Z3,Z6,epo9,E11-21:H), and (3Z,6Z)-henicosa-3,6-dien-11-one (Z3,Z6-21:11-one) for mate communication. To elucidate the P450 candidates associated with the biosynthesis of these sex pheromone components, we sequenced the female D. baibarana pheromone gland and the abdomen excluding the pheromone gland. A total of 75 DbP450s were identified. Function annotation suggested six CYPs were orthologous genes that are linked to molting hormone metabolism, and eight antennae specifically and significantly up-regulated CYPs may play roles in odorant processing. Based on a combination of comparative RNAseq, phylogenetic, and tissue expression pattern analysis, one CYP4G with abdomen specifically predominant expression pattern was likely to be the P450 decarbonylase, while the pheromone-gland specifically and most abundant CYP341B65 was the most promising epoxidase candidate for the D. baibarana sex pheromone biosynthesis. Collectively, our research laid a valuable basis not only for further functional elucidation of the candidate P450 decarbonylase and epoxidase for the sex pheromone biosynthesis but also for understanding the physiological functions and functional diversity of the CYP gene superfamily in the D. baibarana. Full article

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

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9 pages, 1728 KiB

Open AccessArticle

Nutritional Status, Sex, and Ambient Temperature Modulate the Wingbeat Frequency of the Diamondback Moth Plutella xylostella

by Menglun Wang, Jialin Wang, Pei Liang and Kongming Wu

Insects 2024, 15(2), 138; https://doi.org/10.3390/insects15020138 - 19 Feb 2024

Cited by 1 | Viewed by 1544

Abstract

The diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae), is a cosmopolitan horticultural pest that is undergoing a fast, climate-driven range expansion. Its wide geographic distribution, pest status, and high incidence of insecticide resistance are directly tied to long-distance migration. Wingbeat frequency (WBF) is [...] Read more.

The diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae), is a cosmopolitan horticultural pest that is undergoing a fast, climate-driven range expansion. Its wide geographic distribution, pest status, and high incidence of insecticide resistance are directly tied to long-distance migration. Wingbeat frequency (WBF) is a key aspect of P. xylostella migratory behavior, but has received limited scientific attention. Here, we investigated the effects of environmental parameters, age, adult nutrition, and sex on P. xylostella WBF. Across experimental regimes, WBF ranged from 31.39 Hz to 78.87 Hz. Over a 10–35 °C range, the WBF of both male and female moths increased with temperature up to 62.96 Hz. Though male WBF was unaffected by humidity, females exhibited the highest WBF at 15% relative humidity (RH). WBF was unaffected by adult age, but adult nutrition exerted important impacts. Specifically, the WBF of moths fed honey water (54.66 Hz) was higher than that of water-fed individuals (49.42 Hz). Lastly, males consistently exhibited a higher WBF than females. By uncovering the biological and (nutritional) ecological determinants of diamondback moth flight, our work provides invaluable guidance to radar-based monitoring, migration forecasting, and the targeted deployment of preventative mitigation tactics. Full article

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

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15 pages, 2437 KiB

Open AccessArticle

Comparative Transcriptomics Analysis Reveals Rusty Grain Beetle’s Aggregation Pheromone Biosynthesis Mechanism in Response to Starvation

by Fangfang Zeng, Haixin Jiang, Haoqi Xu, Ruotong Shen and Dianxuan Wang

Insects 2024, 15(2), 137; https://doi.org/10.3390/insects15020137 - 19 Feb 2024

Viewed by 1538

Abstract

Pheromones are the basis of insect aggregation, mating, and other behaviors. Cucujoid grain beetles produce macrocyclic lactones as aggregation pheromones, yet research on their biosynthesis at the molecular level remains limited. The rusty grain beetle, C. ferrugineus, is an important economic species [...] Read more.

Pheromones are the basis of insect aggregation, mating, and other behaviors. Cucujoid grain beetles produce macrocyclic lactones as aggregation pheromones, yet research on their biosynthesis at the molecular level remains limited. The rusty grain beetle, C. ferrugineus, is an important economic species in China. Although two aggregation pheromone components have been identified, their suspected biosynthesis via the MVA pathway and the FAS pathway lacks molecular elucidation. Previous evidence supports that starvation affects the production of aggregation pheromones. Therefore, we constructed comparative transcriptome libraries of pheromone production sites in C. ferrugineus under starvation stress and identified genes related to pheromone biosynthesis and hormone regulation. A total of 2665 genes were significantly differentially expressed, of which 2029 genes were down-regulated in starved beetles. Putative C. ferrugineus genes directly involved in pheromone biosynthesis were identified, as well as some genes related to the juvenile hormone (JH) pathway and the insulin pathway, both of which were depressed in the starved beetles, suggesting possible functions in pheromone biosynthesis and regulation. The identification of genes involved in macrolide lactone biosynthesis in vivo holds great significance, aiding in the elucidation of the synthesis and regulatory mechanisms of cucujoid grain beetle pheromones. Full article

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

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15 pages, 3185 KiB

Open AccessArticle

Transcriptomics Provide Insights into the Photoperiodic Regulation of Reproductive Diapause in the Green Lacewing, Chrysoperla nipponensis (Okamoto) (Neuroptera: Chrysopidae)

by Shaoye Liu, Yuqing Gao, Rangjun Shi, Haiyi Huang, Yongyu Xu and Zhenzhen Chen

Insects 2024, 15(2), 136; https://doi.org/10.3390/insects15020136 - 17 Feb 2024

Viewed by 1589

Abstract

Chrysoperla nipponensis (Okamoto) displays typical adult reproductive diapause under short photoperiods; however, our understanding of the molecular mechanism underlying photoperiod-sensitive reproduction remains limited. In this study, we performed transcriptome profiling of four treatments (the diapause-sensitive stage and pre-diapause phase under long and short [...] Read more.

Chrysoperla nipponensis (Okamoto) displays typical adult reproductive diapause under short photoperiods; however, our understanding of the molecular mechanism underlying photoperiod-sensitive reproduction remains limited. In this study, we performed transcriptome profiling of four treatments (the diapause-sensitive stage and pre-diapause phase under long and short photoperiods) of C. nipponensis using RNA sequencing (RNA-seq). A total of 71,654 unigenes were obtained from the samples. Enrichment analysis showed that fatty acid metabolism-related pathways were altered under a short photoperiod. Moreover, β-oxidation-related gene expression was active during the diapause-sensitive period under a short photoperiod. The knockdown of juvenile hormone acid methyltransferase 1 (Jhamt1) prolonged the pre-oviposition period but did not affect the reproductive ability of female individuals in C. nipponensis. These findings provided us with a more comprehensive understanding of the molecular mechanisms of photoperiod-sensitive diapause and show that groundwork is crucial for bolstering the long-term storage and biocontrol potential of C. nipponensis. Full article

(This article belongs to the Special Issue Diapause Regulation and Biological Control of Natural Enemy Insects)

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11 pages, 11971 KiB

Open AccessArticle

Retinal Adaptation in Response to Light and Dark Regimes in the Oriental Armyworm Mythimna separata (Lepidoptera: Noctuidae)

by Qing-Xiao Chen and Ying Han

Insects 2024, 15(2), 135; https://doi.org/10.3390/insects15020135 - 17 Feb 2024

Viewed by 1247

Abstract

The oriental armyworm, Mythimna separata (Walker), is a well-known nocturnal migratory pest that relies on its exceptional nocturnal vision for navigation during long-distance flights. In this study, we investigated the ultrastructure of the compound eyes of adult M. separata using transmission electron microscopy [...] Read more.

The oriental armyworm, Mythimna separata (Walker), is a well-known nocturnal migratory pest that relies on its exceptional nocturnal vision for navigation during long-distance flights. In this study, we investigated the ultrastructure of the compound eyes of adult M. separata using transmission electron microscopy and quantitatively evaluated adaptational changes in the retina under light and dark conditions. The compound eyes of M. separata are superposition eyes with a clear zone. The retina shows remarkable anatomical differences under light and dark adaptation, primarily characterized by distinct patterns of rhabdoms within the clear zone: the rhabdoms are nearly absent under light adaptation, but become more voluminous under dark adaptation. In the distal, middle, and proximal sections of the clear zone, the cross-sectional areas of retinulae and rhabdoms, as well as the rhabdom occupation ratio, are significantly larger under dark adaptation than under light adaptation. Conversely, the opposite trend is observed beneath the clear zone. These results indicate remarkable plasticity in the M. separata retina throughout a normal daily cycle, providing a theoretical basis for improving searchlight and ground light trap techniques for the management of this migratory species. Full article

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

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11 pages, 1510 KiB

Open AccessArticle

Mitogenomes Provide Insights into the Species Boundaries and Phylogenetic Relationships among Three Dolycoris Sloe Bugs (Hemiptera: Pentatomidae) from China

by Chenguang Zheng, Xiuxiu Zhu, Ying Wang, Xue Dong, Ruijuan Yang, Zechen Tang and Wenjun Bu

Insects 2024, 15(2), 134; https://doi.org/10.3390/insects15020134 - 17 Feb 2024

Viewed by 1539

Abstract

(1) Background: The three sloe bugs, Dolycoris baccarum, Dolycoris indicus, and Dolycoris penicillatus, are found in the Chinese mainland and are morphologically similar. The species boundaries and phylogenetic relationships of the three species remain uncertain; (2) Methods: In this study, we [...] Read more.

(1) Background: The three sloe bugs, Dolycoris baccarum, Dolycoris indicus, and Dolycoris penicillatus, are found in the Chinese mainland and are morphologically similar. The species boundaries and phylogenetic relationships of the three species remain uncertain; (2) Methods: In this study, we generated multiple mitochondrial genomes (mitogenomes) for each of the three species and conducted comparative mitogenomic analysis, species delimitation, and phylogenetic analysis based on these data; (3) Results: Mitogenomes of the three Dolycoris species are conserved in nucleotide composition, gene arrangement, and codon usage. All protein-coding genes (PCGs) were found to be under purifying selection, and the ND4 evolved at the fastest rate. Most species delimitation analyses based on the COI gene and the concatenated 13 PCGs retrieved three operational taxonomic units (OTUs), which corresponded well with the three Dolycoris species identified based on morphological characters. A clear-cut barcode gap was discovered between the interspecific and intraspecific genetic distances of the three Dolycoris species. Phylogenetic analyses strongly supported the monophyly of Dolycoris, with interspecific relationship inferred as (D. indicus + (D. baccarum + D. penicillatus)); (4) Conclusions: Our study provides the first insight into the species boundaries and phylogenetic relationships of the three Dolycoris species distributed across the Chinese mainland. Full article

(This article belongs to the Special Issue Phylogeny and Morphological Evolution of Hemiptera)

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19 pages, 5069 KiB

Open AccessArticle

De Novo Genome Assembly at Chromosome-Scale of Hermetia illucens (Diptera Stratiomyidae) via PacBio and Omni-C Proximity Ligation Technology

by Simone Costagli, Linda Abenaim, Giulia Rosini, Barbara Conti and Roberto Giovannoni

Insects 2024, 15(2), 133; https://doi.org/10.3390/insects15020133 - 17 Feb 2024

Cited by 1 | Viewed by 2070

Abstract

Hermetia illucens is a species of great interest for numerous industrial applications. A high-quality reference genome is already available for H. illucens. However, the worldwide maintenance of numerous captive populations of H. illucens, each with its own genotypic and phenotypic characteristics, [...] Read more.

Hermetia illucens is a species of great interest for numerous industrial applications. A high-quality reference genome is already available for H. illucens. However, the worldwide maintenance of numerous captive populations of H. illucens, each with its own genotypic and phenotypic characteristics, made it of interest to perform a de novo genome assembly on one population of H. illucens to define a chromosome-scale genome assembly. By combining the PacBio and the Omni-C proximity ligation technologies, a new H. illucens chromosome-scale genome of 888.59 Mb, with a scaffold N50 value of 162.19 Mb, was assembled. The final chromosome-scale assembly obtained a BUSCO completeness of 89.1%. By exploiting the Omni-C proximity ligation technology, topologically associated domains and other topological features that play a key role in the regulation of gene expression were identified. Further, 65.62% of genomic sequences were masked as repeated sequences, and 32,516 genes were annotated using the MAKER pipeline. The H. illucens Lsp-2 genes that were annotated were further characterized, and the three-dimensional organization of the encoded proteins was predicted. A new chromosome-scale genome assembly of good quality for H. illucens was assembled, and the genomic annotation phase was initiated. The availability of this new chromosome-scale genome assembly enables the further characterization, both genotypically and phenotypically, of a species of interest for several biotechnological applications. Full article

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

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18 pages, 3124 KiB

Open AccessArticle

Developmental Shifts in the Microbiome of a Cosmopolitan Pest: Unraveling the Role of Wolbachia and Dominant Bacteria

by Xiangyu Zhu, Jinyang Li, Ao He, Geoff M. Gurr, Minsheng You and Shijun You

Insects 2024, 15(2), 132; https://doi.org/10.3390/insects15020132 - 16 Feb 2024

Viewed by 1736

Abstract

Wolbachia bacteria (phylum Proteobacteria) are ubiquitous intracellular parasites of diverse invertebrates. In insects, coevolution has forged mutualistic associations with Wolbachia species, influencing reproduction, immunity, development, pathogen resistance, and overall fitness. However, the impact of Wolbachia on other microbial associates within the insect microbiome, [...] Read more.

Wolbachia bacteria (phylum Proteobacteria) are ubiquitous intracellular parasites of diverse invertebrates. In insects, coevolution has forged mutualistic associations with Wolbachia species, influencing reproduction, immunity, development, pathogen resistance, and overall fitness. However, the impact of Wolbachia on other microbial associates within the insect microbiome, which are crucial for host fitness, remains less explored. The diamondback moth (Plutella xylostella), a major pest of cruciferous vegetables worldwide, harbors the dominant Wolbachia strain plutWB1, known to distort its sex ratio. This study investigated the bacterial community diversity and dynamics across different developmental life stages and Wolbachia infection states in P. xylostella using high-throughput 16S rDNA amplicon sequencing. Proteobacteria and Firmicutes dominated the P. xylostella microbiome regardless of life stage or Wolbachia infection. However, the relative abundance of dominant genera, including an unclassified genus of Enterobacteriaceae, Wolbachia, Carnobacterium, and Delftia tsuruhatensis, displayed significant stage-specific variations. While significant differences in bacterial diversity and composition were observed across life stages, Wolbachia infection had no substantial impact on overall diversity. Nonetheless, relative abundances of specific genera differed between infection states. Notably, Wolbachia exhibited a stable, high relative abundance across all stages and negatively correlated with an unclassified genus of Enterobacteriaceae, Delftia tsuruhatensis, and Carnobacterium. Our findings provide a foundational understanding of the complex interplay between the host, Wolbachia, and the associated microbiome in P. xylostella, paving the way for a deeper understanding of their complex interactions and potential implications for pest control strategies. Full article

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

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15 pages, 3232 KiB

Open AccessArticle

Bioassessment of Macroinvertebrate Communities Influenced by Gradients of Human Activities

by Rui Li, Xianfu Li, Ronglong Yang, Muhammad Farooq, Zhen Tian, Yaning Xu, Nan Shao, Shuoran Liu and Wen Xiao

Insects 2024, 15(2), 131; https://doi.org/10.3390/insects15020131 - 14 Feb 2024

Cited by 2 | Viewed by 1768

Abstract

This study explores the impact of anthropogenic land use changes on the macroinvertebrate community structure in the streams of the Cangshan Mountains. Through field collections of macroinvertebrates, measurement of water environments, and delineation of riparian zone land use in eight streams, we analyzed [...] Read more.

This study explores the impact of anthropogenic land use changes on the macroinvertebrate community structure in the streams of the Cangshan Mountains. Through field collections of macroinvertebrates, measurement of water environments, and delineation of riparian zone land use in eight streams, we analyzed the relationship between land use types, stream water environments, and macroinvertebrate diversities. The results demonstrate urban land use type and water temperature are the key environmental factors driving the differences in macroinvertebrate communities up-, mid-, and downstream. The disturbed streams had lower aquatic biodiversity than those in their natural state, showing a decrease in disturbance-sensitive aquatic insect taxa and a more similar community structure. In the natural woodland area, species distributions may be constrained by watershed segmentation and present more complex community characteristics. Full article

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

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13 pages, 2951 KiB

Open AccessArticle

Juvenile Hormone Involved in the Defensive Behaviors of Soldiers in Termite Reticulitermes aculabialis

by Yiying Li, Letong Yin, Ruiyao Guo, Yunliang Du, Bo Wang, Long Liu, Zhenya Li, Wei Liu, Guozhi Zhang, Shiheng An, Xinming Yin and Lijuan Su

Insects 2024, 15(2), 130; https://doi.org/10.3390/insects15020130 - 14 Feb 2024

Viewed by 1792

Abstract

Eusocial insects have evolved specific defensive strategies to protect their colonies. In termite colonies, soldiers perform a colony-level defense by displaying mechanical biting, head-banging and mandible opening–closing behaviors. However, few studies have been reported on the factors modulating defensive behaviors in termites. Owing [...] Read more.

Eusocial insects have evolved specific defensive strategies to protect their colonies. In termite colonies, soldiers perform a colony-level defense by displaying mechanical biting, head-banging and mandible opening–closing behaviors. However, few studies have been reported on the factors modulating defensive behaviors in termites. Owing to JH (juvenile hormone) being involved in soldier differentiation, JH was speculated to affect defensive behaviors in termite soldiers. To determine the effect of JH on the defensive behaviors of termite soldiers, we performed a JHA-feeding and RaSsp1-silencing experiment and then tested the changes in defense-related behaviors, alarm pheromones and key JH signaling genes. The observed result was that after feeding workers with JHA, soldiers displayed the following: (1) decreased biting events and increased head-banging events; (2) a reduced expression of RaSsp1 and increased expression of Met (methoprene-tolerant, the nuclear receptor of JH) and Kr-h1 (the JH-inducible transcription factor Krüppel homolog 1); and (3) a decreased concentration of alarm pheromones, including α-pinene, β-pinene and limonene (+, −). Further study showed that soldiers silenced for RaSsp1 also exhibited (1) decreased biting events and increased head-banging events and (2) increased expression of Met and Kr-h1. In addition, soldiers stimulated by the alarm pheromone limonene displayed an increase in the frequency of mandible opening–closing and biting behavior. All of these results show that JHA influenced the defensive behaviors of termite soldiers, possibly via downregulating RaSsp1 expression, up-regulating Met and Kr-h1 and stimulating the secretion of alarm pheromones, suggesting that the JH pathway plays important roles in modulating social behaviors in termite colonies. Full article

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

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11 pages, 2137 KiB

Open AccessArticle

Blue Light Attracts More Spodoptera frugiperda Moths and Promotes Their Flight Speed

by Haibo Yang, Jing Lu, Pinhong Zhu, Yalan Sun, Zhenjie Hu, Dingxu Li and Jianrong Huang

Insects 2024, 15(2), 129; https://doi.org/10.3390/insects15020129 - 14 Feb 2024

Cited by 2 | Viewed by 1681

Abstract

Light traps are a useful method for monitoring and controlling the important migratory pest, the fall armyworm, Spodoptera frugiperda. Studies have shown that S. frugiperda is sensitive to blue, green, or ultraviolet (UV) light, but the conclusions are inconsistent. Furthermore, conventional black [...] Read more.

Light traps are a useful method for monitoring and controlling the important migratory pest, the fall armyworm, Spodoptera frugiperda. Studies have shown that S. frugiperda is sensitive to blue, green, or ultraviolet (UV) light, but the conclusions are inconsistent. Furthermore, conventional black light traps are less effective for trapping S. frugiperda. To improve the trapping efficiency of this pest, it is crucial to determine the specific wavelength to which S. frugiperda is sensitive and measure its flight capability under that wavelength. This study investigated the effects of light wavelength on the phototaxis and flight performance of S. frugiperda. The results showed that blue light was the most sensitive wavelength among the three different LED lights and was unaffected by gender. The flight capability of S. frugiperda varied significantly in different light conditions, especially for flight speed. The fastest flight speed was observed in blue light, whereas the slowest was observed in UV light compared to dark conditions. During a 12 h flight period, speed declined more rapidly in blue light and more slowly in UV, whereas speed remained stable in dark conditions. Meanwhile, the proportion of fast-flying individuals was highest under blue light, which was significantly higher than under UV light. Therefore, the use of light traps equipped with blue LED lights can improve the trapping efficiency of S. frugiperda. These results also provide insights for further research on the effects of light pollution on migratory insects. Full article

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

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18 pages, 3895 KiB

Open AccessArticle

Barcoding Fails to Delimit Species in Mongolian Oedipodinae (Orthoptera, Acrididae)

by Lea-Sophie Kock, Elisabeth Körs, Martin Husemann, Lkhagvasuren Davaa and Lara-Sophie Dey

Insects 2024, 15(2), 128; https://doi.org/10.3390/insects15020128 - 12 Feb 2024

Cited by 3 | Viewed by 2013

Abstract

Mongolia, a country in central Asia, with its vast grassland areas represents a hotspot for Orthoptera diversity, especially for the Acrididae. For Mongolia, 128 Acrididae species have been documented so far, of which 41 belong to the subfamily Oedipodinae (band-winged grasshoppers). Yet, few [...] Read more.

Mongolia, a country in central Asia, with its vast grassland areas represents a hotspot for Orthoptera diversity, especially for the Acrididae. For Mongolia, 128 Acrididae species have been documented so far, of which 41 belong to the subfamily Oedipodinae (band-winged grasshoppers). Yet, few studies concerning the distribution and diversity of Oedipodinae have been conducted in this country. Molecular genetic data is almost completely absent, despite its value for species identification and discovery. Even, the simplest and most used data, DNA barcodes, so far have not been generated for the local fauna. Therefore, we generated the first DNA barcode data for Mongolian band-winged grasshoppers and investigated the resolution of this marker for species delimitation. We were able to assemble 105 DNA barcode (COI) sequences of 35 Oedipodinae species from Mongolia and adjacent countries. Based on this data, we reconstructed maximum likelihood and Bayesian inference phylogenies. We, furthermore, conducted automatic barcode gap discovery and used the Poisson tree process (PTP) for species delimitation. Some resolution was achieved at the tribe and genus level, but all delimitation methods failed to differentiate species by using the COI region. This lack of resolution may have multiple possible reasons, which likely differ between taxa: the lack of resolution in the Bryodemini may be partially explained by their massive genomes, implying the potential presence of large numbers of pseudogenes, while within the Sphingonotini incomplete lineage sorting and incorrect taxonomy are more likely explanations for the lack of signal. Further studies based on a larger number of gene fragments, including nuclear DNA, are needed to distinguish the species also at the molecular level. Full article

(This article belongs to the Special Issue Locusts and Grasshoppers: Bionomics, Distribution, and Population Management)

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12 pages, 1039 KiB

Open AccessArticle

Global Trends in Climate Suitability of Bees: Ups and Downs in a Warming World

by Ehsan Rahimi and Chuleui Jung

Insects 2024, 15(2), 127; https://doi.org/10.3390/insects15020127 - 11 Feb 2024

Cited by 9 | Viewed by 3525

Abstract

Bees represent vital natural assets contributing significantly to global food production and the maintenance of ecosystems. While studies on climate change effects impacting major pollinators like honeybees and bumblebees raise concerns about global diversity and crop productivity, comprehensive global-scale analyses remain limited. This [...] Read more.

Bees represent vital natural assets contributing significantly to global food production and the maintenance of ecosystems. While studies on climate change effects impacting major pollinators like honeybees and bumblebees raise concerns about global diversity and crop productivity, comprehensive global-scale analyses remain limited. This study explores the repercussions of global warming on 1365 bees across seven families of bees worldwide. To compile a robust global bee occurrence dataset, we utilized the innovative ‘BeeBDC’ R package that amalgamated over 18.3 million bee occurrence records sourced from various repositories. Through species distribution models under the SSP585 scenario in the year 2070, we assessed how climate change influences the climate suitability of bees on a global scale, examining the impacts across continents. Our findings suggested that approximately 65% of bees are likely to witness a decrease in their distribution, with reductions averaging between 28% in Australia and 56% in Europe. Moreover, our analysis indicated that climate change’s impact on bees is projected to be more severe in Africa and Europe, while North America is expected to witness a higher number (336) of bees expanding their distribution. Climate change’s anticipated effects on bee distributions could potentially disrupt existing pollinator–plant networks, posing ecological challenges that emphasize the importance of pollinator diversity, synchrony between plants and bees, and the necessity for focused conservation efforts. Full article

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

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14 pages, 4659 KiB

Open AccessArticle

Integrative Analyses of Transcriptomics and Metabolomics in Immune Response of Leguminivora glycinivorella Mats to Beauveria bassiana Infection

by Hongqiang Fei, Juan Cui, Shiyu Zhu, Ye Xia, Yichang Xing, Yu Gao and Shusen Shi

Insects 2024, 15(2), 126; https://doi.org/10.3390/insects15020126 - 10 Feb 2024

Viewed by 1907

Abstract

This study utilized Beauveria bassiana to infect Leguminivora glycinivorella, analyzed the effects on the transcriptome and metabolome, and further investigated the antibacterial function of L. glycinivorella. We performed transcriptome and metabolome sequencing on the L. glycinivorella infected with B. bassiana and [...] Read more.

This study utilized Beauveria bassiana to infect Leguminivora glycinivorella, analyzed the effects on the transcriptome and metabolome, and further investigated the antibacterial function of L. glycinivorella. We performed transcriptome and metabolome sequencing on the L. glycinivorella infected with B. bassiana and its control groups, and performed a joint analysis of transcriptome and metabolome results. Upon screening, 4560 differentially expressed genes were obtained in the transcriptome and 71 differentially expressed metabolites were obtained in the metabolome. On this basis, further integration of the use of transcriptomics and metabonomics combined an analysis of common enrichments of pathways of which there were three. They were glutathione S-transferase (GSTs) genes, heat shock protein (HSP) genes, and cytochrome P450 (CYP450) genes. These three pathways regulate the transport proteins, such as ppars, and thus affect the digestion and absorption of sugars and fats, thus regulating the development of pests. The above conclusion indicates that B. bassiana can affect the sugar metabolism, lipid metabolism, and amino acid metabolism pathways of L. glycinivorella, and can consume the necessary energy, protein, and lipids of L. glycinivorella. The research on the immune response mechanism of pests against pathogens can provide an important scientific basis and target for the development of immunosuppressants. This study laid an information foundation for the application of entomogenous fungi to control soybean borer at the molecular level. Full article

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

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12 pages, 2463 KiB

Open AccessArticle

Demography and Behaviour of Teinopodagrion oscillans (Odonata: Megapodagrionidae) in a Protected Area of the Colombian Andean Region

by Fredy Palacino-Rodríguez, Diego Andres Palacino, Andrea Penagos Arevalo and Adolfo Cordero-Rivera

Insects 2024, 15(2), 125; https://doi.org/10.3390/insects15020125 - 9 Feb 2024

Cited by 1 | Viewed by 1718

Abstract

The demography and behaviour of Teinopodagrion oscillans was studied in a protected area in the Andean region of Colombia. Adult damselflies were individually marked, and using their recapture histories, we estimated survival, longevity, sex ratio, and population size using Cormack-Jolly-Seber models. Other aspects [...] Read more.

The demography and behaviour of Teinopodagrion oscillans was studied in a protected area in the Andean region of Colombia. Adult damselflies were individually marked, and using their recapture histories, we estimated survival, longevity, sex ratio, and population size using Cormack-Jolly-Seber models. Other aspects of their behaviour were recorded. Survival, recapture, and lifespan (14.1 ± 0.59 days) were similar for both sexes and all age groups. Mature males were larger, and the distance from the water was similar for all individuals. The most supported model was the time-dependent model for survival and recapture. This suggests that weather variations affect the demography of this population in a significant way. Individuals exhibited high fidelity to their site perch, perching with open wings near water on a variety of perches. Mature males make short flights from the perch to intercept conspecific and interspecific males and to hunt prey. The tandem position was formed on macrophytes, and then the pair flew away. Oviposition lasted for 11.23 min on average, with the females ovipositing by abdomen submersion. Our results offer insights into the demographic characteristics and behaviour of this species, providing crucial information for the short- and long-term, from the demography of one species to the conservation of ecosystems of the Andean region. Full article

(This article belongs to the Special Issue Aquatic Insects: Diversity, Ecology and Evolution)

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18 pages, 3627 KiB

Open AccessArticle

Effect of Microclimate on the Mass Emergence of Hypothenemus hampei in Coffee Grown under Shade of Trees and in Full Sun Exposure

by Valentina García-Méndez, Rebeca González-Gómez, Jorge Toledo, Javier Francisco Valle-Mora and Juan F. Barrera

Insects 2024, 15(2), 124; https://doi.org/10.3390/insects15020124 - 9 Feb 2024

Cited by 3 | Viewed by 1572

Abstract

The rainfall regime has a significant impact on the microclimate and mass emergence of the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae) (CBB). Little is known, however, about the shade tree–microclimate–CBB mass emergence interaction. The objective of the present study was to compare [...] Read more.

The rainfall regime has a significant impact on the microclimate and mass emergence of the coffee berry borer, Hypothenemus hampei (Coleoptera: Curculionidae) (CBB). Little is known, however, about the shade tree–microclimate–CBB mass emergence interaction. The objective of the present study was to compare the effect of microclimate on the mass emergence of CBB in a full sun-exposed plot with a plot shaded by trees. The experiment was conducted on a Robusta coffee farm in southern Chiapas, Mexico. In each plot, 18 traps baited with an alcohol mixture were installed to capture flying females, collecting caught individuals every hour from 8:00 to 18:00 h. A meteorological station recorded several microclimatic variables on 13 weekly sampling dates from February to May 2022. Significantly more CBB females were captured in the shaded plot. The largest number of CBB captures was recorded between 14:00 and 16:00 h for the shade plot and between 15:00 and 17:00 h for the sun-exposed plot. The mass emergence of CBB showed a positive association with precipitation, dew point, and wind speed samples and a negative association with maximum air temperature, average relative humidity, ultraviolet radiation, wind speed, and equilibrium moisture content. Our observations show that the relationship between shade trees, microclimate, and mass emergence of CBB is complex and that its study helps us to gain deeper insight into CBB bioecology and advance control techniques against this important pest. Full article

(This article belongs to the Special Issue Biology, Ecology, and Management of the Coffee Berry Borer (Hypothenemus hampei))

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10 pages, 1081 KiB

Open AccessArticle

Pierid Butterflies, Legume Hostplants, and Parasitoids in Urban Areas of Southern Florida

by Suzanne Koptur, Andrea Salas Primoli, Hipólito Ferreira Paulino-Neto and James Whitfield

Insects 2024, 15(2), 123; https://doi.org/10.3390/insects15020123 - 9 Feb 2024

Viewed by 1389

Abstract

Are parasitoids less likely to find their Lepidoptera hosts on non-native hostplants than native hostplants? We predicted that with longer periods of coevolution between herbivores and the plants they consume, the parasitoids that provide top-down control would be more attuned to finding their [...] Read more.

Are parasitoids less likely to find their Lepidoptera hosts on non-native hostplants than native hostplants? We predicted that with longer periods of coevolution between herbivores and the plants they consume, the parasitoids that provide top-down control would be more attuned to finding their hosts on native plants. To test this hypothesis, we collected immature stages of sulfur butterflies (the cloudless sulfur (Phoebis sennae) and the orange-barred sulfur (Phoebis agarithe) over a three-year period (2008–2011) from native and ornamental hostplants in the genus Senna in three different parts of the urban landscape of Miami, Florida, USA. We reared the immature specimens to pupation and either eclosion of adults or emergence of parasitoids and compared the levels of parasitization among the three areas, and among native vs. exotic hostplants. We found, contrary to our prediction, that caterpillars feeding on non-native leguminous hostplant species were more likely to be parasitized than those feeding on native hostplants. We discuss this surprising finding in the light of recent findings in other plant/herbivore/parasitoid systems. Full article

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

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19 pages, 17446 KiB

Open AccessArticle

Functional Anatomy of Split Compound Eyes of the Whirligig Beetles Dineutus mellyi (Coleoptera: Gyrinidae)

by Jacob Muinde, Tian-Hao Zhang, Zu-Long Liang, Si-Pei Liu, Esther Kioko, Zheng-Zhong Huang and Si-Qin Ge

Insects 2024, 15(2), 122; https://doi.org/10.3390/insects15020122 - 7 Feb 2024

Cited by 1 | Viewed by 1780

Abstract

The functional anatomy of the split compound eyes of whirligig beetles Dineutus mellyi (Coleoptera: Gyrinidae) was examined by advanced microscopy and microcomputed tomography. We report the first 3D visualization and analysis of the split compound eyes. On average, the dorsal and ventral eyes [...] Read more.

The functional anatomy of the split compound eyes of whirligig beetles Dineutus mellyi (Coleoptera: Gyrinidae) was examined by advanced microscopy and microcomputed tomography. We report the first 3D visualization and analysis of the split compound eyes. On average, the dorsal and ventral eyes contain 1913 ± 44.5 facets and 3099 ± 86.2 facets, respectively. The larger area of ventral eyes ensures a higher field of vision underwater. The ommatidium of the split compound eyes is made up of laminated cornea lenses that offer protection against mechanical injuries, bullet-shaped crystalline cones that guide light to the photoreceptive regions, and screening pigments that ensure directional light passage. The photoreceptive elements, made up of eight retinular cells, exhibit a tri-tiered rhabdom structure, including the upper distal rhabdom, a clear zone that ensures maximum light passage, and an enlarged lower distal rhabdom that ensures optimal photon capture. Full article

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

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17 pages, 7819 KiB

Open AccessArticle

Morphological Characterization of the Antenna and Scent Patch of Three Danaus Species (Papilionoidea: Nymphalidae, Danainae)

by Yaqi Yang, Linyun Ding, Tong Wang, Huaijian Liao and Chufei Tang

Insects 2024, 15(2), 121; https://doi.org/10.3390/insects15020121 - 7 Feb 2024

Cited by 1 | Viewed by 1957

Abstract

The scent system of Danaus is important for the study of butterfly sexual communication and relevant investigations in biomimetics due to its involvement with mimicry. Using light, scanning, and transmission electron microscopy, the morphological characteristics of Danaus’ antennae and scent patches of [...] Read more.

The scent system of Danaus is important for the study of butterfly sexual communication and relevant investigations in biomimetics due to its involvement with mimicry. Using light, scanning, and transmission electron microscopy, the morphological characteristics of Danaus’ antennae and scent patches of the scent system for three species, D. chrysippus, D. genutia, and D. plexippus, were investigated herein. Their apical clubs of the flagellums contain sensilla trichodea, sensilla chaetica, and sensilla coeloconica. The scent patch scales typically have a tree-like structure in its lumen at the nano-scale. Comparisons were made between the androconial scales and the other scales in scent patches. Rank sum tests showed significant differences in scent patch scales’ characteristics between the species, as well as in the ultrastructure of antennal segments between species and sexes. Spearman’s correlation tests showed significant correlations between the morphological characteristics of androconial scales in scent patches. Moreover, the antennal characteristics were significantly correlated. The morphological characteristics of the females’ antennae were significantly correlated with those of the males’ antennae and androconial scales. However, the significance and coefficient of these correlations were inconsistent across species and sexes. This study provides fundamental morphological information that helps in understanding the pheromone recognition system of Danaus. Full article

(This article belongs to the Collection Insect Sensory Biology)

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12 pages, 1748 KiB

Open AccessArticle

Widespread Resistance to Temephos in Aedes aegypti (Diptera: Culicidae) from Mexico

by Jesus A. Davila-Barboza, Selene M. Gutierrez-Rodriguez, Alan E. Juache-Villagrana, Beatriz Lopez-Monroy and Adriana E. Flores

Insects 2024, 15(2), 120; https://doi.org/10.3390/insects15020120 - 7 Feb 2024

Cited by 2 | Viewed by 2245

Abstract

Organic synthetic insecticides continue to be part of the arsenal for combating vector-borne diseases in Mexico. Larvicides are a fundamental part of the process in programs for mosquito control, temephos being one of the most widely used in Mexico. In the present study, [...] Read more.

Organic synthetic insecticides continue to be part of the arsenal for combating vector-borne diseases in Mexico. Larvicides are a fundamental part of the process in programs for mosquito control, temephos being one of the most widely used in Mexico. In the present study, we analyzed the frequency of temephos resistance in twenty-three Aedes aegypti populations using the discriminating concentration (DC) of 0.012 mg/L. We also tested 5× DC (0.6 mg/L) and 10× DC (0.12 mg/L) of temephos. The resistance distribution to temephos was interpolated to unsampled sites using the inverse distance weighting (IDW) method. The populations of Ae. aegypti showed a high frequency of resistance (1× DC) with mortality rates below 93% in 22 of the 23 populations analyzed. Moderate resistance intensity (5× DC) was found in 78% of the populations, and high intensity (10× DC) in 30%. Predicted mortality was below 60% in the populations of the Pacific Coast, along the Gulf of Mexico, and in the state of Coahuila in Northeastern Mexico in relation to 1× DC; the Pacific Coast and Northeast patterns hold for 5× and 10× DC. The results suggest the need for rotation of the larvicide to effectively control the larval populations of the vector in the country. Full article

(This article belongs to the Special Issue Insecticide Resistance: Challenge to Pest Management and Basic Research)

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17 pages, 2233 KiB

Open AccessArticle

Measurement of Fitness and Predatory Ability of Four Predatory Mite Species in Tibetan Plateau under Laboratory Conditions

by Dong Xiang, Zhen Wang, Long Xu, Yunchao Wang, Huanhuan Zhang and Kun Yang

Insects 2024, 15(2), 119; https://doi.org/10.3390/insects15020119 - 6 Feb 2024

Cited by 1 | Viewed by 1544

Abstract

Predatory mites are biological control agents used in many countries against various vegetable pests, particularly spider mites. Despite the significant presence of predatory mites in the Tibetan plateau, there is limited research on their potential against spider mites in the area. This study [...] Read more.

Predatory mites are biological control agents used in many countries against various vegetable pests, particularly spider mites. Despite the significant presence of predatory mites in the Tibetan plateau, there is limited research on their potential against spider mites in the area. This study investigated the fitness parameters and performance against TSSM of four predatory, including Amblyseius swirskii (Athias-Henriot) and three species from the genus Neoseiulus (Neoseiulus californicus (McGregor), Neoseiulus barkeri (Hughes), and Neoseiulus cucumeris (Oudemans)), originally collected from fields in the Tibetan Plateau. Compared to the other three predatory species, A. swirskii exhibited the highest fecundity (11.60 ± 0.34) and the highest pre-adult survival rate (83.33 ± 3.33%). Since their juvenile survival rate (SR) was extremely low (13.33% ± 5.77%), most N. barkeri nymphs died before emergence. Compared to the other three predatory mites, A. swirskii showed the highest predation capacity against adult TSSMs at 15 d post-release (14.28 ± 2.24). Based on the results, A. swirskii was the most effective, and N. barkeri was the least effective in controlling two-spotted mites in the Tibetan Plateau among the four species tested in this study. Collectively, these findings imply notable advantages in employing A. swirskii for controlling two-spotted mites in the Tibetan Plateau. This study informs the development of a feasible biological control method based on suitable predatory mite species to manage TSSMs in the Tibetan Plateau. Full article

(This article belongs to the Special Issue Diapause Regulation and Biological Control of Natural Enemy Insects)

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39 pages, 7111 KiB

Open AccessArticle

Pseudolycoriella hygida (Sauaia and Alves)—An Overview of a Model Organism in Genetics, with New Aspects in Morphology and Systematics

by Frank Menzel, Katja Kramp, Dalton de Souza Amorim, Eduardo Gorab, João Vitor Cardoso Uliana, Heni Sauaia and Nadia Monesi

Insects 2024, 15(2), 118; https://doi.org/10.3390/insects15020118 - 6 Feb 2024

Cited by 1 | Viewed by 2260

Abstract

Pseudolycoriella hygida (Sauaia & Alves, 1968) is a sciarid that has been continuously cultured in the laboratory for nearly 60 years. Studies on this species have contributed to the understanding of DNA puffs, which are characteristic of Sciaridae, and to the knowledge of [...] Read more.

Pseudolycoriella hygida (Sauaia & Alves, 1968) is a sciarid that has been continuously cultured in the laboratory for nearly 60 years. Studies on this species have contributed to the understanding of DNA puffs, which are characteristic of Sciaridae, and to the knowledge of more general aspects of insect biology, including cell death, nucleolar organization, and the role of the hormone ecdysone during molting. The genome of Psl. hygida has now been sequenced, and it is the third publicly available sciarid genome. The aim of this work is to expand the current knowledge on Psl. hygida. The morphology of the adults is revisited. The morphology of larvae and pupae is described, together with the behavior of immature stages under laboratory conditions. Cytogenetic maps of the salivary gland polytene chromosomes are presented, together with a comparative analysis of the mitotic chromosomes of six different sciarid species. Pseudolycoriella hygida was originally described as a species of Bradysia and recently moved to Pseudolycoriella. We examine here the systematic position of Psl. hygida in the latter genus. Our results extend the characterization of an unconventional model organism and constitute an important resource for those working on the cytogenetics, ecology, taxonomy, and phylogenetic systematics of sciarids. Full article

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

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12 pages, 1758 KiB

Open AccessArticle

First Report of the Association of the Psyllid Vector Bactericera trigonica (Hemiptera: Triozidae) with ‘Candidatus Liberibacter Solanacearum’ in Italy

by Giorgia Bertinelli, Lorenza Tizzani, Fabio Mosconi, Vincenza Ilardi and Sabrina Bertin

Insects 2024, 15(2), 117; https://doi.org/10.3390/insects15020117 - 6 Feb 2024

Cited by 1 | Viewed by 1400

Abstract

Psyllids, members of the family Triozidae, represent a potential threat to the cultivation of solanaceous and apiaceous crops worldwide, mainly as vectors of the phloem-restricted bacterium ‘Candidatus Liberibacter solanacearum’ (Lso). The Lso haplotypes C, D and E are known to affect apiaceous [...] Read more.

Psyllids, members of the family Triozidae, represent a potential threat to the cultivation of solanaceous and apiaceous crops worldwide, mainly as vectors of the phloem-restricted bacterium ‘Candidatus Liberibacter solanacearum’ (Lso). The Lso haplotypes C, D and E are known to affect apiaceous crops, such as carrot and celery, in several European countries. In Italy, data on the incidence and natural spread of both Lso and psyllids have not been reported so far. In this study, the presence of the vectors was investigated in a main Italian district for carrot production, the “Altopiano del Fucino” area (Central Italy). Both occasional and regular surveys were carried out on a total of five carrot fields and one potato field in 2021 and 2022. Bactericera trigonica (Hodkinson), which is known to efficiently transmit Lso to carrots, was found to be well-established in the area. High levels of population density were recorded in the summer period (more than 100 adult specimens per trap caught every two weeks) and then sharply decreased after the carrot harvest, confirming the strict association of this psyllid species with crop availability. In 2022, 27.5% of the total tested psyllid samples resulted in being positive for Lso haplotypes D and E, the latter being prevalent. This survey revealed, for the first time in Italy, the presence of B. trigonica adults associated with Lso in carrot crops. Although this study was limited to a few fields located in one area, it provided important evidence of the risks for Lso outbreaks and prompted further research to assess the spread and incidence of the disease in apiaceous cultivations in Italy. Full article

(This article belongs to the Special Issue Insect Vectors of Plant Diseases)

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14 pages, 2024 KiB

Open AccessArticle

Fine-Scale Genetic Structure of Curculio chinensis (Coleoptera: Curculionidae) Based on Mitochondrial COI: The Role of Host Specificity and Spatial Distance

by Li Zhang, Fuping Wang, Jiaxi Wu, Sicheng Ye, Ye Xu and Yanan Liu

Insects 2024, 15(2), 116; https://doi.org/10.3390/insects15020116 - 6 Feb 2024

Viewed by 1191

Abstract

The Camellia weevil, Curculio chinensis (Chevrolat, 1978), is a dominant oligophagous pest that bores into the fruit of oil-tea Camellia. Genetic differentiation among populations in various hosts can easily occur, which hinders research on pest management. In this study, the genetic structure, [...] Read more.

The Camellia weevil, Curculio chinensis (Chevrolat, 1978), is a dominant oligophagous pest that bores into the fruit of oil-tea Camellia. Genetic differentiation among populations in various hosts can easily occur, which hinders research on pest management. In this study, the genetic structure, genetic diversity, and phylogenetic structure of local C. chinensis populations were examined using 147 individuals (from 6 localities in Jiangxi), based on 2 mitochondrial COI markers. Results indicated that the C. chinensis population in Jiangxi exhibits a high haplotype diversity, especially for the populations from Cam. meiocarpa plantations. Structural differentiation was observed between Haplogroup 1 (73 individuals from Ganzhou, Jian, and Pingxiang) in the monoculture plantations of Cam. meiocarpa and Haplogroup 2 (75 individuals from Pingxiang and Jiujiang) in Cam. oleifera. Two haplogroups have recently undergone a demographic expansion, and Haplogroup 1 has shown a higher number of effective migrants than Haplogroup 2. This suggests that C. chinensis has been spreading from Cam. meiocarpa plantations to other oil-tea Camellia, such as Cam. oleifera. The increased cultivation of oil-tea Camellia in Jiangxi has contributed to a unique genetic structure within the C. chinensis population. This has, in turn, expanded the distribution of C. chinensis and increased migration between populations. Full article

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

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14 pages, 3789 KiB

Open AccessArticle

Integrated Pest Management Strategies to Control Varroa Mites and Their Effect on Viral Loads in Honey Bee Colonies

by Jernej Bubnič, Janez Prešern, Marco Pietropaoli, Antonella Cersini, Ajda Moškrič, Giovanni Formato, Veronica Manara and Maja Ivana Smodiš Škerl

Insects 2024, 15(2), 115; https://doi.org/10.3390/insects15020115 - 5 Feb 2024

Cited by 1 | Viewed by 3232

Abstract

Honey bee viruses in combination with varroa mite are very damaging for honey bee colonies worldwide. There are no effective methods to control the viral load in honey bee colonies except regular and effective control of mites. Integrated Pest Management strategies are required [...] Read more.

Honey bee viruses in combination with varroa mite are very damaging for honey bee colonies worldwide. There are no effective methods to control the viral load in honey bee colonies except regular and effective control of mites. Integrated Pest Management strategies are required to effectively control mites with veterinary medicines based on organic compounds. We evaluated the effect of two brood interruption techniques, queen caging (QC) and trapping comb (TC), followed by an oxalic acid treatment, on the mite fall, colony strength, and viral load of Deformed Wing Virus (DWV) and Acute Bee Paralysis Virus (ABPV). In this paper, we report the data obtained in two experimental sites, in Slovenia and Italy, in terms of the varroacide efficacy, colony strength, and viral load. The number of adult bees after the adoption of the two techniques showed similar decreasing trends in both locations. The viral load of Acute Bee Paralysis Virus did not show any significant reduction after 25 days, reported as the number of Real-Time PCR cycles needed to detect the virus. The viral load of DWV also did not show a significant reduction after 25 days. The acaricidal efficacy of the applied protocols was high in both experimental groups and in both apiaries. Both the queen caging and trapping comb techniques, followed by an oxalic acid treatment, can be considered effective varroa treatment strategies, but further studies should be carried out to evaluate the long-term effects on viral loads to plan the Integrated Pest Management strategy with the right timing before wintering. Full article

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

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30 pages, 8833 KiB

Open AccessArticle

A Review of Chinese Species of the Genus Oides Weber, 1801 (Coleoptera: Chrysomelidae: Galerucinae)

by Meixia Yang, Jian Shen, Changping Ding and Xingke Yang

Insects 2024, 15(2), 114; https://doi.org/10.3390/insects15020114 - 5 Feb 2024

Cited by 1 | Viewed by 1830

Abstract

In this study, 25 species of Oides Weber from China were reviewed. Among them, the following seven new species are described: Oides angustasp. nov., O. cystoprocessasp. nov., O. paraborerisp. nov., O. parabowringiisp. nov., O. parathibettana [...] Read more.

In this study, 25 species of Oides Weber from China were reviewed. Among them, the following seven new species are described: Oides angustasp. nov., O. cystoprocessasp. nov., O. paraborerisp. nov., O. parabowringiisp. nov., O. parathibettanasp. nov., O. shimenensissp. nov., and O. yunnanensissp. nov.; Oides innocua Gahan has been recorded in China for the first time. A key to all the Chinese Oides species is provided. Full article

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

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12 pages, 1836 KiB

Open AccessArticle

The Genome of Arsenophonus sp. and Its Potential Contribution in the Corn Planthopper, Peregrinus maidis

by Yu-Hui Wang, Aram Mikaelyan, Brad S. Coates and Marcé Lorenzen

Insects 2024, 15(2), 113; https://doi.org/10.3390/insects15020113 - 5 Feb 2024

Cited by 1 | Viewed by 2012

Abstract

The co-evolution between symbionts and their insect hosts has led to intricate functional interdependencies. Advances in DNA-sequencing technologies have not only reduced the cost of sequencing but, with the advent of highly accurate long-read methods, have also enabled facile genome assembly even using [...] Read more.

The co-evolution between symbionts and their insect hosts has led to intricate functional interdependencies. Advances in DNA-sequencing technologies have not only reduced the cost of sequencing but, with the advent of highly accurate long-read methods, have also enabled facile genome assembly even using mixed genomic input, thereby allowing us to more easily assess the contribution of symbionts to their insect hosts. In this study, genomic data recently generated from Peregrinus maidis was used to assemble the genome of a bacterial symbiont, Pm Arsenophonus sp. This ~4.9-Mb assembly is one of the largest Arsenophonus genomes reported to date. The Benchmarking Universal Single-Copy Orthologs (BUSCO) result indicates that this Pm Arsenophonus assembly has a high degree of completeness, with 96% of the single-copy Enterobacterales orthologs found. The identity of the Pm Arsenophonus sp. was further confirmed by phylogenetic analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicates a major contribution by Pm Arsenophonus sp. to the biosynthesis of B vitamins and essential amino acids in P. maidis, where threonine and lysine production is carried out solely by Pm Arsenophonus sp. This study not only provides deeper insights into the evolutionary relationships between symbionts and their insect hosts, but also adds to our understanding of insect biology, potentially guiding the development of novel pest control methods. Full article

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

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14 pages, 4993 KiB

Open AccessArticle

Hive Orientation and Colony Strength Affect Honey Bee Colony Activity during Almond Pollination

by Sandra Kordić Evans, Huw Evans, William G. Meikle and George Clouston

Insects 2024, 15(2), 112; https://doi.org/10.3390/insects15020112 - 5 Feb 2024

Viewed by 2717

Abstract

The foraging activity of honey bees used to pollinate almonds was examined in relation to their hive entrance orientation and colony strength. Twenty-four colonies of honey bees, twelve in each group, were situated with their entrances facing east and west cardinal points. Bee [...] Read more.

The foraging activity of honey bees used to pollinate almonds was examined in relation to their hive entrance orientation and colony strength. Twenty-four colonies of honey bees, twelve in each group, were situated with their entrances facing east and west cardinal points. Bee out counts were recorded continuously and hive weight data at ∼10 min intervals from 17 February to 15 March 2023. Colony strength was assessed using the frames of adult bees (FOB) metric. East-facing hives started flight 44.2 min earlier than west-facing hives. The hive direction did not affect the timing of the cessation of foraging activity. The hive strength played a significant role: hives assessed as weak (≤3.0 FOB) commenced foraging activity 45 min later than strong hives (>3.0 FOB) and ceased foraging activity 38.3 min earlier. Hive weight data did not detect effects of either the hive direction or colony strength on the commencement and cessation of foraging activity, as determined using piecewise regression on 24 h datasets. However, the hive weight loss due to foraging activity at the start of foraging activity was significantly affected by both direction (East > West) and colony strength (Strong > Weak). Our study showed that, during almond pollination, both hive entrance exposure and hive strength have quantifiable effects on colony foraging behaviour and that these effects combine to regulate the overall foraging activity of the pollinating colonies. Full article

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

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16 pages, 10386 KiB

Open AccessArticle

The Molecular and Functional Characterization of Sensory Neuron Membrane Protein 1b (SNMP1b) from Cyrtotrachelus buqueti (Coleoptera: Curculionidae)

by Hua Yang, Long Liu, Fan Wang, Wei Yang, Qiong Huang, Nanxi Wang and Hongling Hu

Insects 2024, 15(2), 111; https://doi.org/10.3390/insects15020111 - 4 Feb 2024

Cited by 2 | Viewed by 1416

Abstract

Sensory neuron membrane proteins (SNMPs) play important roles in insect chemoreception and SNMP1s have been reported to be essential in detecting sex pheromones in Drosophila and some lepidopteran species. However, SNMPs for Cyrtotrachelus buqueti (Coleoptera: Curculionidae), a major insect pest of bamboo plantations, [...] Read more.

Sensory neuron membrane proteins (SNMPs) play important roles in insect chemoreception and SNMP1s have been reported to be essential in detecting sex pheromones in Drosophila and some lepidopteran species. However, SNMPs for Cyrtotrachelus buqueti (Coleoptera: Curculionidae), a major insect pest of bamboo plantations, remain uncharacterized. In this study, a novel SNMP gene, CbuqSNMP1b, from C. buqueti was functionally characterized. The expression of CbuqSNMP1b was significantly higher in antennae than in other tissues of both sexes and the expression level was significantly male-biased. Additionally, CbuqSNMP1b showed significantly higher transcription levels in the adult stage and very low transcription levels in other stages, suggesting that CbuqSNMP1b is involved in the process of olfaction. Fluorescence binding assays indicated that CbuqSNMP1b displayed the strongest binding affinity to dibutyl phthalate (K_i = 9.03 μM) followed by benzothiazole (K_i = 11.59 μM) and phenol (K_i = 20.95 μM) among fourteen C. buqueti volatiles. Furthermore, molecular docking revealed key residues in CbuqSNMP1b that interact with dibutyl phthalate, benzothiazole, and phenol. In conclusion, these findings will lay a foundation to further understand the olfactory mechanisms of C. buqueti and promote the development of novel methods for controlling this pest. Full article

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

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14 pages, 2411 KiB

Open AccessArticle

Effect of Guanylate Cyclase-22-like on Ovarian Development of Orius nagaii (Hemiptera: Anthocoridae)

by Huiling Du, Ruijuan Wang, Xiaoyan Dai, Zhenjuan Yin, Yan Liu, Long Su, Hao Chen, Shan Zhao, Li Zheng, Xiaolin Dong and Yifan Zhai

Insects 2024, 15(2), 110; https://doi.org/10.3390/insects15020110 - 4 Feb 2024

Cited by 1 | Viewed by 1560

Abstract

This study identified and characterized the gene encoding recep tor-type guanylate cyclase-22-like (GCY-22; OnGCY) from the pirate bug Orius nagaii, an important biological control agent. The full-length cDNA of the GCY of O. nagaii was obtained by rapid amplification of cDNA [...] Read more.

This study identified and characterized the gene encoding recep tor-type guanylate cyclase-22-like (GCY-22; OnGCY) from the pirate bug Orius nagaii, an important biological control agent. The full-length cDNA of the GCY of O. nagaii was obtained by rapid amplification of cDNA ends (RACE); it had a total length of 4888 base pairs (bp), of which the open reading frame (ORF) was 3750 bp, encoding a polypeptide of 1249 amino acid residues. The physicochemical properties of OnGCY were predicted and analyzed by using relevant ExPASy software, revealing a molecular formula of C6502H10122N1698O1869S57, molecular weight of ~143,811.57 kDa, isoelectric point of 6.55, and fat index of 90.04. The resulting protein was also shown to have a signal peptide, two transmembrane regions, and a conserved tyrosine kinase (tyrkc). Silencing OnGCY by RNA interference significantly inhibited ovarian development and decreased fertility in female O. nagaii in the treated versus the control group. Additionally, OnGCY silencing significantly decreased the expression levels of other GCY and Vg genes. Thus, these results clarify the structure and biological function of OnGCY, which has an important role in insect fecundity. The results also provide a reference for agricultural pest control and future large-scale breeding of biological control agents. Full article

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

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