Insects

22 pages, 7630 KiB

Open AccessArticle

Transcriptomic and Gene Expression Analysis of Chemosensory Genes from White Grubs of Hylamorpha elegans (Coleoptera: Scarabaeidae), a Subterranean Pest in South America

by Paula Lizana, Ana Mutis, Rubén Palma-Millanao, Giovanni Larama, Binu Antony, Andrés Quiroz and Herbert Venthur

Insects 2024, 15(9), 660; https://doi.org/10.3390/insects15090660 (registering DOI) - 30 Aug 2024

Abstract

Olfaction and gustation processes play key roles in the life cycle of insects, such as finding and accepting food sources, oviposition sites, and mates, among other fundamental aspects of insect development. In this context, chemosensory genes found in sensory organs (e.g., antennae and [...] Read more.

Olfaction and gustation processes play key roles in the life cycle of insects, such as finding and accepting food sources, oviposition sites, and mates, among other fundamental aspects of insect development. In this context, chemosensory genes found in sensory organs (e.g., antennae and maxillary palps) are crucial for understanding insect behaviour, particularly the phytophagous behaviour of insect pests that attack economically important crops. An example is the scarab beetle Hylamorpha elegans, which feeds on the roots of several crops important for livestock in its larval stage. In this study, chemosensory gene candidates of H. elegans white grubs identified through the head transcriptome and phylogenetic and tissue-biased gene expression (antennae, head without antennae, and legs) have been reported. Overall, 47 chemosensory genes were identified (2 ORs, 1 GR, 11 IRs, 9 CSPs, and 24 OBPs). Gene expression analysis revealed the predominant presence of IRs in the legs, whereas ORs and the GR were present in the heads and/or antennae. Particularly, HeleOBP9 and HeleCSP2 were significantly expressed in the head but not in the antennae or legs; these and other genes are discussed as potential targets in the context of H. elegans management. Full article

(This article belongs to the Special Issue Insect Chemosensory Systems and Semiochemicals: From Molecular Genetics to Neuroethology)

► Show Figures

Figure 1

13 pages, 901 KiB

Open AccessArticle

Geographic Location, Population Dynamics, and Fruit Damage of an Invasive Citrus Mealybug: The Case of Delottococcus aberiae De Lotto in Eastern Spain

by Aitor Gavara, Sandra Vacas and Vicente Navarro-Llopis

Insects 2024, 15(9), 659; https://doi.org/10.3390/insects15090659 (registering DOI) - 30 Aug 2024

Abstract

The invasive mealybug Delottococcus aberiae De Lotto (Hemiptera: Pseudococcidae) has rapidly spread in the Mediterranean basin since its detection in 2009 in the Valencia Community in eastern Spain. The use of sticky traps baited with its sex pheromone, (4,5,5-trimethyl-3-methylenecyclopent-1-en-1-yl)methyl acetate, has allowed to [...] Read more.

The invasive mealybug Delottococcus aberiae De Lotto (Hemiptera: Pseudococcidae) has rapidly spread in the Mediterranean basin since its detection in 2009 in the Valencia Community in eastern Spain. The use of sticky traps baited with its sex pheromone, (4,5,5-trimethyl-3-methylenecyclopent-1-en-1-yl)methyl acetate, has allowed to determine the geographical distribution of D. aberiae by means of the surveillance network described in the present work. The population monitoring of the pest over a five-year period (2019–2023) has revealed an increase from 31% to 70% of the affected citrus-growing area. The monitoring network has also allowed a better understanding of the pests’ biological cycle throughout the year. The populations start growing from March to June and reach their maximum in July–August. During autumn, there is a gradual decline in the population. Although the highest annual populations were detected in 2022 and 2023, the greatest crop losses were recorded in 2020 and 2021, with mean values near 18%. Data suggest that the damage responsible for fruit deformation, and thus the economic losses, are related to the population levels in spring (April–May) rather than those in summer (July–August). The findings of this study can be valuable for future research and development of effective pest control strategies. Full article

(This article belongs to the Collection Balancing Nature: Biological Control Introductions for Invasive Insect Pests and Weeds)

13 pages, 2468 KiB

Open AccessArticle

Recent Southern Hemisphere Lamprimine Stag Beetle in Cretaceous Burmese Amber and Its Biogeographic Implications (Coleoptera: Lucanidae)

by Yali Yu, Zhenhua Liu, Zhiqiang Li and Chenyang Cai

Insects 2024, 15(9), 658; https://doi.org/10.3390/insects15090658 (registering DOI) - 30 Aug 2024

Abstract

A new stag beetle fossil, Prostreptocerus burmiticus Yu & Cai gen. et sp. nov., is described based on a single male specimen. This is the first representative of the subfamily Lampriminae (Coleoptera: Scarabaeoidea: Lucanidae) from mid-Cretaceous Burmese amber. The new species is distinctive [...] Read more.

A new stag beetle fossil, Prostreptocerus burmiticus Yu & Cai gen. et sp. nov., is described based on a single male specimen. This is the first representative of the subfamily Lampriminae (Coleoptera: Scarabaeoidea: Lucanidae) from mid-Cretaceous Burmese amber. The new species is distinctive among Lucanidae due to its well-developed, right-angled mandible, frons featuring a pair of large protuberances, a coarse and sparsely punctate elytral disc, and large tubercles on the humeri. Prostreptocerus Yu & Cai is placed within Lampriminae based on several key characteristics. Morphologically, it is most similar to the extant Streptocerus Fairmaire, 1850. The current distribution of Streptocerus and Lampriminae is primarily restricted to the Southern Hemisphere, suggesting that this lineage is ancient and existed on Gondwanaland, which has significant geographical implications. This discovery extends the fossil record of Lampriminae and provides additional evidence for the existence of sexual dimorphism and potential combat behavior in Mesozoic lucanids. Additionally, Electraesalopsis Bai, Zhang & Qiu, 2017, previously placed as Lucanidae incertae sedis, shares many characteristics with Prostreptocerus Yu & Cai and is also assigned to Lampriminae based on a suite of traits. Full article

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

► Show Figures

Figure 1

18 pages, 2888 KiB

Open AccessArticle

Genetic Diversity of Whiteflies Colonizing Crops and Their Associated Endosymbionts in Three Agroecological Zones of Cameroon

by Lanvin R. K. Kepngop, Everlyne N. Wosula, Massoud Amour, Pierre G. T. Ghomsi, Louise N. Wakam, Germain Kansci and James P. Legg

Insects 2024, 15(9), 657; https://doi.org/10.3390/insects15090657 (registering DOI) - 30 Aug 2024

Abstract

Bemisia tabaci (Gennadius) is as a major pest of vegetable crops in Cameroon. These sap-sucking insects are the main vector of many viruses infecting plants, and several cryptic species have developed resistance against insecticides. Nevertheless, there is very little information about whitefly species [...] Read more.

Bemisia tabaci (Gennadius) is as a major pest of vegetable crops in Cameroon. These sap-sucking insects are the main vector of many viruses infecting plants, and several cryptic species have developed resistance against insecticides. Nevertheless, there is very little information about whitefly species on vegetable crops and the endosymbionts that infect them in Cameroon. Here, we investigated the genetic diversity of whiteflies and their frequency of infection by endosymbionts in Cameroon. Ninety-two whitefly samples were collected and characterized using mitochondrial cytochrome oxidase I (mtCOI) markers and Kompetitive Allele Specific PCR (KASP). The analysis of mtCOI sequences of whiteflies indicated the presence of six cryptic species (mitotypes) of Bemisia tabaci, and two distinct clades of Bemisia afer and Trialeurodes vaporariorum. Bemisia tabaci mitotypes identified included: MED on tomato, pepper, okra, and melon; and SSA1-SG1, SSA1-SG2, SSA1-SG5, SSA3, and SSA4 on cassava. The MED mitotype predominated in all regions on the solanaceous crops, suggesting that MED is probably the main phytovirus vector in Cameroonian vegetable cropping systems. The more diverse cassava-colonizing B. tabaci were split into three haplogroups (SNP-based grouping) including SSA-WA, SSA4, and SSA-ECA using KASP genotyping. This is the first time that SSA-ECA has been reported in Cameroon. This haplogroup is predominant in regions currently affected by the severe cassava mosaic virus disease (CMD) and cassava brown streak virus disease (CBSD) pandemics. Three endosymbionts including Arsenophonus, Rickettsia, and Wolbachia were present in female whiteflies tested in this study with varying frequency. Arsenophonus, which has been shown to influence the adaptability of whiteflies, was more frequent in the MED mitotype (75%). Cardinium and Hamiltonella were absent in all whitefly samples. These findings add to the knowledge on the diversity of whiteflies and their associated endosymbionts, which, when combined, influence virus epidemics and responses to whitefly control measures, especially insecticides. Full article

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

► Show Figures

Figure 1

12 pages, 6437 KiB

Open AccessArticle

Evaluation of Anopheline Diversity and Abundance across Outdoor Collection Schemes Utilizing CDC Light Traps in Nchelenge District, Zambia

by Christine M. Jones, Ilinca I. Ciubotariu, Mary E. Gebhardt, James Sichivula Lupiya, David Mbewe, Mbanga Muleba, Jennifer C. Stevenson and Douglas E. Norris

Insects 2024, 15(9), 656; https://doi.org/10.3390/insects15090656 (registering DOI) - 30 Aug 2024

Abstract

In the global fight against malaria, standard vector control methods such as indoor residual spraying (IRS) and insecticide-treated nets (ITNs) are intended to protect inside residential structures and sleeping spaces. However, these methods can still leave individuals vulnerable to residual transmission from vectors [...] Read more.

In the global fight against malaria, standard vector control methods such as indoor residual spraying (IRS) and insecticide-treated nets (ITNs) are intended to protect inside residential structures and sleeping spaces. However, these methods can still leave individuals vulnerable to residual transmission from vectors that they may be exposed to outdoors. Nchelenge District in northern Zambia experiences persistently high malaria transmission even with ITNs and IRS in place. However, very few studies have examined outdoor vector activity. To assess the diversity and abundance of outdoor foraging female anopheline mosquitoes, CDC light traps were used as proxy measures for mosquito host-seeking, set in three outdoor trapping schemes randomly assigned on different nights: (1) locations where people congregate at night outside of the house within the peri-domestic space, (2) animal pens or shelters, and (3) high-human-traffic areas, such as paths to latrines, where traps were baited with BG-Lure^®. A total of 1087 total female anophelines were collected over a total of 74 trap nights. Anopheles funestus s.s. comprised the majority of the collection (86%), with An. gambiae s.s. (2%) and a highly diverse sampling of other anophelines (12%) making up the remainder. Plasmodium falciparum parasites were only detected in An. funestus (1%). No significant difference in species diversity or female anopheline abundance was detected between trapping schemes. Outdoor foraging anopheline mosquitoes, including a number of infectious An. funestus, may partially explain the difficulty of controlling malaria transmission in Nchelenge District, where vector control is only targeted indoors. BG-Lure^® shows some promise as an alternative to human-baited landing catch collections in this resource-poor setting. Full article

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

► Show Figures

Figure 1

15 pages, 13563 KiB

Open AccessArticle

Comparative Morphology and Ultrastructure of Antennal Sensilla in Dendrolimus superans (Lepidoptera: Lasiocampidae) and Lymantria dispar (Lepidoptera: Lymantriidae)

by Qi Wang, Longzheng Wang, Qing Wang and Shanchun Yan

Insects 2024, 15(9), 655; https://doi.org/10.3390/insects15090655 (registering DOI) - 30 Aug 2024

Viewed by 101

Abstract

Dendrolimus superans (Lepidoptera: Lasiocampidae) and Lymantria dispar (Lepidoptera: Lymantriidae) are two important forest defoliators in northeast China, with the former being a specialist on Larix spp. and the latter being a generalist feeding on >500 species of plants. The morphology and ultrastructure of [...] Read more.

Dendrolimus superans (Lepidoptera: Lasiocampidae) and Lymantria dispar (Lepidoptera: Lymantriidae) are two important forest defoliators in northeast China, with the former being a specialist on Larix spp. and the latter being a generalist feeding on >500 species of plants. The morphology and ultrastructure of antennal sensilla of both male and female D. superans and L. dispar were examined using scanning electron microscopy (SEM). In both sexes of D. superans, the following five types of antennal sensilla were found: sensilla trichoidea, s. chaetica, s. coeloconica, s. gemmiformia, and s. basiconica. In males of L. dispar, six types of antennal sensilla: sensilla trichoidea, s. chaetica, s. coeloconica, s. basiconica, s. styloconica, and s. auricillica, were identified. In addition to the six types found in males, a seventh type of sensilla, s. squamiform, was only detected on L. dispar female antennae. For s. chaetica of D. superans, a unique ultrastructure of sub-branches that have one branch, two branches, and three branches was observed on their tips, which has not yet been reported on other insects. s. styloconica, s. auricillica, and s. squamiform, not found in the specialist D. superans, may be related to the euryphagy of L. dispar. Potential functionalities of these sensilla were discussed with reference to moth feeding habits, and their morphology, distribution, and ultrastructures on both species. Full article

► Show Figures

Figure 1

13 pages, 852 KiB

Open AccessReview

Tracking Existing Factors Directly Affecting the Reproduction of Bumblebees: Current Knowledge

by Xiaomeng Zhao, Jingxin Jiang, Zilin Pang, Weihua Ma, Yusuo Jiang, Yanfang Fu and Yanjie Liu

Insects 2024, 15(9), 654; https://doi.org/10.3390/insects15090654 (registering DOI) - 30 Aug 2024

Viewed by 142

Abstract

Bumblebees are primary social insects and a vital class of pollinating insects. Their distinctive reproductive mode is characterized by the independent initiation and construction of the nest by the queen and the subsequent production of sufficient workers, males, and gynes following colony development. [...] Read more.

Bumblebees are primary social insects and a vital class of pollinating insects. Their distinctive reproductive mode is characterized by the independent initiation and construction of the nest by the queen and the subsequent production of sufficient workers, males, and gynes following colony development. After successful mating, the queen transitions to the first phase of its annual life cycle. The reproductive processes are directly influenced by environmental factors, including floral resources and pesticides. Moreover, the reproductive level is regulated by biological factors, particularly the role of workers, who participate in egg laying and pass on their genetic material to the next generation of queens. Successful reproduction can only be achieved by maintaining colony development under natural or artificial breeding conditions. Consequently, understanding the known factors that influence bumblebee reproduction is essential for developing conservation strategies for wild bumblebees and for successfully breeding diverse bumblebee species. Breeding various bumblebee species is crucial for in-depth research into known factors and for further exploration of other potential factors, which will also help to meet the demand for pollination in agricultural facilities globally. Full article

(This article belongs to the Special Issue Arthropod Reproductive Biology)

► Show Figures

Figure 1

22 pages, 1500 KiB

Open AccessReview

Advancements and Future Prospects of CRISPR-Cas-Based Population Replacement Strategies in Insect Pest Management

by Yu Zhao, Longfeng Li, Liangzi Wei, Yifan Wang and Zhilin Han

Insects 2024, 15(9), 653; https://doi.org/10.3390/insects15090653 (registering DOI) - 30 Aug 2024

Viewed by 238

Abstract

Population replacement refers to the process by which a wild-type population of insect pests is replaced by a population possessing modified traits or abilities. Effective population replacement necessitates a gene drive system capable of spreading desired genes within natural populations, operating under principles [...] Read more.

Population replacement refers to the process by which a wild-type population of insect pests is replaced by a population possessing modified traits or abilities. Effective population replacement necessitates a gene drive system capable of spreading desired genes within natural populations, operating under principles akin to super-Mendelian inheritance. Consequently, releasing a small number of genetically edited insects could potentially achieve population control objectives. Currently, several gene drive approaches are under exploration, including the newly adapted CRISPR-Cas genome editing system. Multiple studies are investigating methods to engineer pests that are incapable of causing crop damage or transmitting vector-borne diseases, with several notable successful examples documented. This review summarizes the recent advancements of the CRISPR-Cas system in the realm of population replacement and provides insights into research methodologies, testing protocols, and implementation strategies for gene drive techniques. The review also discusses emerging trends and prospects for establishing genetic tools in pest management. Full article

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

► Show Figures

Figure 1

37 pages, 1665 KiB

Open AccessReview

Virulence Adaptation by Rice Planthoppers and Leafhoppers to Resistance Genes and Loci: A Review

by Finbarr G. Horgan

Insects 2024, 15(9), 652; https://doi.org/10.3390/insects15090652 - 29 Aug 2024

Viewed by 138

Abstract

In recent decades, research on developing and deploying resistant rice has accelerated due to the availability of modern molecular tools and, in particular, advances in marker-assisted selection. However, progress in understanding virulence adaptation has been relatively slow. This review tracks patterns in virulence [...] Read more.

In recent decades, research on developing and deploying resistant rice has accelerated due to the availability of modern molecular tools and, in particular, advances in marker-assisted selection. However, progress in understanding virulence adaptation has been relatively slow. This review tracks patterns in virulence adaptation to resistance genes (particularly Bph1, bph2, Bph3, and bph4) and examines the nature of virulence based on selection experiments, responses by virulent populations to differential rice varieties (i.e., varieties with different resistance genes), and breeding experiments that interpret the genetic mechanisms underlying adaptation. The review proposes that varietal resistance is best regarded as a combination of minor and major resistance traits against which planthoppers develop partial or complete virulence through heritable improvements that are reversable or through evolutionary adaptation, respectively. Agronomic practices, deployment patterns, and herbivore population pressures determine the rates of adaptation, and there is growing evidence that pesticide detoxification mechanisms can accelerate virulence adaptation. Research to delay adaptation has mainly focused on gene pyramiding (i.e., including ≥ two major genes in a variety) and multilines (i.e., including ≥ two resistant varieties in a field or landscape); however, these strategies have not been adequately tested and, if not managed properly, could inadvertently accelerate adaptation compared to sequential deployment. Several research gaps remain and considerable improvements in research methods are required to better understand and manage virulence adaptation. Full article

(This article belongs to the Collection Plant Responses to Insect Herbivores)

► Show Figures

Figure 1

23 pages, 1001 KiB

Open AccessReview

MALDI-TOF MS Profiling and Its Contribution to Mosquito-Borne Diseases: A Systematic Review

by Monique Melo Costa, Vincent Corbel, Refka Ben Hamouda and Lionel Almeras

Insects 2024, 15(9), 651; https://doi.org/10.3390/insects15090651 - 29 Aug 2024

Viewed by 255

Abstract

Mosquito-borne diseases are responsible for hundreds of thousands of deaths per year. The identification and control of the vectors that transmit pathogens to humans are crucial for disease prevention and management. Currently, morphological classification and molecular analyses via DNA barcoding are the standard [...] Read more.

Mosquito-borne diseases are responsible for hundreds of thousands of deaths per year. The identification and control of the vectors that transmit pathogens to humans are crucial for disease prevention and management. Currently, morphological classification and molecular analyses via DNA barcoding are the standard methods used for vector identification. However, these approaches have several limitations. In the last decade, matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS) profiling has emerged as an innovative technology in biological sciences and is now considered as a relevant tool for the identification of pathogens and arthropods. Beyond species identification, this tool is also valuable for determining various life traits of arthropod vectors. The purpose of the present systematic review was to highlight the contribution of MALDI-TOF MS to the surveillance and control of mosquito-borne diseases. Published articles from January 2003 to August 2024 were retrieved, focusing on different aspects of mosquito life traits that could be determinants in disease transmission and vector management. The screening of the scientific literature resulted in the selection of 54 published articles that assessed MALDI-TOF MS profiling to study various mosquito biological factors, such species identification, life expectancy, gender, trophic preferences, microbiota, and insecticide resistance. Although a large majority of the selected articles focused on species identification, the present review shows that MALDI-TOF MS profiling is promising for rapidly identifying various mosquito life traits, with high-throughput capacity, reliability, and low cost. The strengths and weaknesses of this proteomic tool for vector control and surveillance are discussed. Full article

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

► Show Figures

Graphical abstract

16 pages, 4988 KiB

Open AccessArticle

Leg Attachment Devices of Tiger Beetles (Coleoptera, Cicindelidae) and Their Relationship to Their Habitat Preferences

by Zheng Liu, Stanislav N. Gorb, Hongbin Liang, Ming Bai and Yuanyuan Lu

Insects 2024, 15(9), 650; https://doi.org/10.3390/insects15090650 - 29 Aug 2024

Viewed by 171

Abstract

The ability of many insects to adhere vertically or even upside down to smooth substrates is closely related to the morphology and distribution of the adhesive structures on their legs. During locomotion, the legs are in direct contact with different substrates, and it [...] Read more.

The ability of many insects to adhere vertically or even upside down to smooth substrates is closely related to the morphology and distribution of the adhesive structures on their legs. During locomotion, the legs are in direct contact with different substrates, and it is hypothesized that the adhesive structures have been evolved as an adaption to smooth substrates in specific environments. To investigate whether there is a relationship between the presence of adhesive structures and the combined effects of different environments and mating behavior, we compared five species of tiger beetles belonging to two tribes living in arboreal and non-arboreal environments, respectively. In three non-arboreal species, we found a specific type of adhesive structure consisting of elongated spoon-like setae present on the protarsi of males but absent on the male meso- and metatarsi and on females. In Tricondyla pulchripes, an arboreal species living on stems, we found three types of adhesive setae on male protarsi, while only two types of setae were found on male meso- and metatarsi and on females. In Neocollyris linearis, an arboreal species living on leaves, we found three types of adhesive setae on male pro-, meso- and meta-tarsi but only two types of adhesive setae on females. The adaptive evolution of these adhesive structures was probably driven by the selective pressures of both mating behavior and the presence of smooth substrates in the respective environments. It is discussed that the adhesive structures in tiger beetles may be an adaptive evolutionary response to the plant surfaces and may play an important role in species differentiation. Full article

► Show Figures

Graphical abstract

13 pages, 2870 KiB

Open AccessArticle

New Records of Sharpshooters (Hemiptera, Cicadellidae, Cicadellinae) in Citrus Orchards in Amazonas State, Brazil

by Paola Victoria Moreno Franco, Joyce Adriana Froza, Nathalia Hiluy Pecly, João Roberto Spotti Lopes, Jânia Lilia da Silva Bentes Lima and Agno Nonato Serrão Acioli

Insects 2024, 15(9), 649; https://doi.org/10.3390/insects15090649 - 29 Aug 2024

Viewed by 188

Abstract

This research study reports new records of eight species of Cicadellini (Hemiptera, Cicadellidae, Cicadellinae) across seven municipalities in Amazonas State, Brazil. Among these species, one is known as a vector of CVC (Provancherana corniculata). Additionally, five species are being reported for [...] Read more.

This research study reports new records of eight species of Cicadellini (Hemiptera, Cicadellidae, Cicadellinae) across seven municipalities in Amazonas State, Brazil. Among these species, one is known as a vector of CVC (Provancherana corniculata). Additionally, five species are being reported for the first time in citrus for the State (Erythrogonia sexguttata, Hortensia similis, Provancherana corniculata, Scopogonalia amazonensis, and Scoposcartula oculata), and three species (Diedrocephala variegata, Macugonalia moesta and Xyphon reticulatum) are reported for the first time in the northern region. This research highlights the lack of information on sharpshooter occurrence in the Amazonas region, emphasizing the need for further investigations in this area. Full article

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

► Show Figures

Figure 1

15 pages, 3988 KiB

Open AccessArticle

Evolutionary Relationships of Omani Macrotermes subhyalinus, Macrotermitinae

by Hilal S. AlShamakhi, Abdullah M. Al-Sadi and Lyn G. Cook

Insects 2024, 15(9), 648; https://doi.org/10.3390/insects15090648 - 29 Aug 2024

Viewed by 216

Abstract

A study was conducted to investigate the evolutionary relationships of Macrotermes subhyalinus from Oman, in the southeastern part of the Arabian Peninsula. Sequences of the mitochondrial COI and the nuclear large-subunit ribosomal RNA (LSU rRNA, 28S) genes were used to investigate the [...] Read more.

A study was conducted to investigate the evolutionary relationships of Macrotermes subhyalinus from Oman, in the southeastern part of the Arabian Peninsula. Sequences of the mitochondrial COI and the nuclear large-subunit ribosomal RNA (LSU rRNA, 28S) genes were used to investigate the populations of M. subhyalinus across their distribution in Oman to determine their relationships with other Macrotermes species. Our findings indicate that M. subhyalinus in Oman is a member of an East African clade, distinct from those in West Africa. Analyses of the COI showed that there is base composition bias among the taxa (non-stationarity) that has not been considered in earlier studies. We provide the first report of pseudogene copies of 28S in M. subhyalinus that are differentially amplified. Full article

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

► Show Figures

Figure 1

15 pages, 2317 KiB

Open AccessArticle

Sublethal Effects of Pyridaben on the Predatory Function of Neoseiulus womersleyi

by Cancan Song, Chengcheng Li, Juan Wei, Hualan Zeng, Qunfang Yang, Surong Jiang, Chunxian Jiang and Qing Li

Insects 2024, 15(9), 647; https://doi.org/10.3390/insects15090647 - 28 Aug 2024

Viewed by 187

Abstract

Pyridaben is a widely utilized, broad-spectrum contact acaricide, which has notable sublethal effects that impair the predatory capabilities of predatory mites, but the specific mechanisms that affect the predatory functions remain underexplored. When predatory mites hunt for prey, they may rely on Niemann–Pick-type [...] Read more.

Pyridaben is a widely utilized, broad-spectrum contact acaricide, which has notable sublethal effects that impair the predatory capabilities of predatory mites, but the specific mechanisms that affect the predatory functions remain underexplored. When predatory mites hunt for prey, they may rely on Niemann–Pick-type C2 (NPC2) proteins to collect herbivore-induced plant volatiles (HIPVs) and other odor molecules to locate and pursue their prey. This study elucidated that pyridaben significantly diminished the predatory efficiency and searching behavior of the predatory mite Neoseiulus womersleyi. Key metrics, including predatory capacity (a/Th) and predation rate (a) on various developmental stages of Tetranychus urticae, were markedly reduced in treated mites compared to controls. The searching efficiency (S) also declined proportionally with the increased sublethal dose of pyridaben. A gene linked to olfactive functions, NwNPC2a, was cloned from N. womersleyi. Post-treatment with pyridaben at LC₃₀ and LC₅₀ concentrations resulted in a substantial downregulation of NwNPC2a expression by 60.15% and 58.63%, respectively. Silencing NwNPC2a in N. womersleyi females led to significant reductions in the attack rate (a), handling time (Th), predation efficiency (a/Th), and maximum predation rate (1/Th). The searching efficiency (S) was also lower than that of the control group, displaying a slight decline with the increasing prey density. The findings revealed that pyridaben exerted inhibitory effects on both the predatory function and searching efficiency of N. womersleyi populations. The decrease in predatory performance at LC₃₀ and LC₅₀ concentrations was attributable to the suppression of NwNPC2a gene expression. RNA interference (RNAi) studies corroborated that the NwNPC2a gene plays a critical role in the predation process of N. womersleyi. Thus, the underlying molecular mechanism through which pyridaben compromises the predatory function of N. womersleyi likely involves the downregulation of NwNPC2a expression. Full article

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

► Show Figures

Graphical abstract

12 pages, 2246 KiB

Open AccessArticle

Characteristics and Comparative Analysis of Six Mitogenomes of Genus Kiefferulus Goetghebuer, 1922 (Diptera: Chironomidae)

by Dan Zhang, Wei-Dong Jin, Hai-Feng Xu, Xue-Bo Li, Yong-Wei Jiang, Dai-Qing Li and Xiao-Long Lin

Insects 2024, 15(9), 646; https://doi.org/10.3390/insects15090646 - 28 Aug 2024

Viewed by 242

Abstract

Chironomidae is a cosmopolitan and species-rich family of insects, with many species serving as useful indicators of aquatic ecosystem health. In this study, we newly sequenced six species of Kiefferulus Goetghebuer, 1922 (Chironomidae: Chironominae) by high-throughput sequencing technology. We analyzed characters of the [...] Read more.

Chironomidae is a cosmopolitan and species-rich family of insects, with many species serving as useful indicators of aquatic ecosystem health. In this study, we newly sequenced six species of Kiefferulus Goetghebuer, 1922 (Chironomidae: Chironominae) by high-throughput sequencing technology. We analyzed characters of the mitochondrial genome, including the sequence length, nucleotide composition, and evolutionary rates of this genus. The size of the newly obtained sequences ranged from 15,588 to 15,767 bp, and all of them included 22 tRNAs, 13 PCGs, 2 rRNAs, and 1 CR. The CR showed the highest AT content relative to the PCGs, rRNAs, and tRNAs. Relative synonymous codon usage analysis showed that UUA, UUU, and AUU are the preferred codons. The ratio of nonsynonymous (Ka) to synonymous (Ks) substitution rates showed that all Ka/Ks of PCGs were lower than 1, with ATP8 having the highest evolution rate, while COX1 exhibited the lowest evolution rate. We reconstructed the phylogenetic relationship of the genus Kiefferulus based on eight species (six ingroups and two outgroups), using five matrices and employing Maximum likelihood and Bayesian inference approaches. Phylogenetic analysis of the Kiefferulus showed that six species within this genus were classified into a monophyletic clade. Full article

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

► Show Figures

Figure 1

14 pages, 5432 KiB

Open AccessArticle

Consumption and Digestion of Plastics by Greater Hive Moth Larvae

by Andrés Felipe Arias-González, Luis David Gómez-Méndez and Adriana Sáenz-Aponte

Insects 2024, 15(9), 645; https://doi.org/10.3390/insects15090645 - 28 Aug 2024

Viewed by 305

Abstract

The accumulation and unsustainable management of plastic waste generate environmental pollution that affects ecosystems, wildlife, and human health. We studied the possibility of using the consumption and digestion of oxo-biodegradable, compostable plastics and polypropylene from face masks by the fifth-instar larvae of G. [...] Read more.

The accumulation and unsustainable management of plastic waste generate environmental pollution that affects ecosystems, wildlife, and human health. We studied the possibility of using the consumption and digestion of oxo-biodegradable, compostable plastics and polypropylene from face masks by the fifth-instar larvae of G. mellonella as a strategy for the sustainable management of plastic waste. We used Fourier transform infrared spectrophotometry (FTIR) to determine the percentage of consumption and presence of microplastics in the digestive tract and excreta for 10 treatments evaluated for 135 h. The effects of plastics on the continuity of the life cycle of the greater hive moth were also determined. We established that the larvae fragmented and consumed 35.2 ± 23% of the plastics evaluated, with significant differences between treatments. Larvae were able to consume more of the intermediate layers of masks (86.31%) than the other plastics. However, none of the plastics were digested. Instead, microplastics accumulated in the excreta, resulting in nutritional deficits that affected the continuity of the life cycle, including the induction of the early formation of pupae after 24 h and a reduction in the number of eggs laid by the females. Full article

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

► Show Figures

Graphical abstract

15 pages, 2294 KiB

Open AccessArticle

Combined Toxic Effects of Lead and Glyphosate on Apis cerana cerana

by Yunfei Xue, Wenzheng Zhao, Qingxin Meng, Linfu Yang, Dandan Zhi, Yulong Guo, Dan Yue, Yakai Tian and Kun Dong

Insects 2024, 15(9), 644; https://doi.org/10.3390/insects15090644 - 27 Aug 2024

Viewed by 241

Abstract

Glyphosate (GY) is the most widely used herbicide in agriculture worldwide. Lead is a common heavy metal in the natural environment. Honeybees, as pollinators, are exposed to these pollutants. So far, few reports have evaluated the toxic effects of GY mixed with heavy [...] Read more.

Glyphosate (GY) is the most widely used herbicide in agriculture worldwide. Lead is a common heavy metal in the natural environment. Honeybees, as pollinators, are exposed to these pollutants. So far, few reports have evaluated the toxic effects of GY mixed with heavy metals on honeybees (Apis cerana cerana). This study found that the acute toxicity of lead (LC50 = 1083 mg/L) is much greater than that of GY (LC50 = 4764 mg/L) at 96 h. The acute toxicities of the mixed substances were as follows: LC50 = 621 mg/L of lead and LC50 = 946 mg/L of GY. The combination of lead and GY was more toxic than either of the individual substances alone. Compared to the individual toxicity, combined treatment significantly affected the bees’ learning and cognitive abilities and changed the relative expression of genes related to immune defense and detoxification metabolism in A. c. cerana. The combination of lead and GY seriously affected the behavior and physiology of the studied honeybees. This study provides basic data for further research on the combined effects of GY and heavy metals on bee health. It also serves as a reference for effective colony protection. Full article

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

► Show Figures

Figure 1

12 pages, 1590 KiB

Open AccessArticle

BmToll9-1 Is a Positive Regulator of the Immune Response in the Silkworm Bombyx mori

by Jisheng Liu, Weijian Chen, Jinrong Situ, Jiaxuan Li, Jiahua Chen, Minchun Lai, Fengyi Huang and Baoqi Li

Insects 2024, 15(9), 643; https://doi.org/10.3390/insects15090643 - 27 Aug 2024

Viewed by 319

Abstract

Toll receptors are involved in the development and innate immunity of insects. BmToll9-1 is an important immune receptor in the Toll pathway. Previous studies have focused on its role as a receptor in immune response. In this study, we aimed to investigate the [...] Read more.

Toll receptors are involved in the development and innate immunity of insects. BmToll9-1 is an important immune receptor in the Toll pathway. Previous studies have focused on its role as a receptor in immune response. In this study, we aimed to investigate the role of BmToll9-1 as a regulator in the immune response. The expression profiles demonstrated that BmToll9-1 was predominantly expressed in the midgut. RNA interference (RNAi) of BmToll9-1 was found to be effective in the midgut via the injection of dsRNA, which resulted in smaller and lighter larvae and cocoons. Most signaling genes in the Toll pathway and downstream effector genes were downregulated after the RNAi of BmToll9-1. The hemolymph from BmToll9-1-silenced larvae showed decreased antibacterial activity against Escherichia coli, either in growth curve or inhibition zone experiments. The above results indicate that BmToll9-1 might be positively involved in the immune pathway of silkworm. As a positive regulator, BmToll9-1 might function mainly in the gut to maintain microbial homeostasis to regulate the growth of silkworms. Silencing of BmToll9-1 downregulates the signaling genes in the Toll pathway and antimicrobial peptide (AMP) production, resulting in decreased antibacterial activity in the hemolymph. Full article

(This article belongs to the Collection Insect Immunity: Evolution, Genomics and Physiology)

► Show Figures

Figure 1

14 pages, 3868 KiB

Open AccessArticle

Phylogenetic and Comparative Analysis of Cryptochironomus, Demicryptochironomus and Harnischia Inferred from Mitogenomes (Diptera: Chironomidae)

by Wenbin Liu, Chengyan Wang, Jingyuan Wang, Yaning Tang, Wenxuan Pei, Xinyu Ge and Chuncai Yan

Insects 2024, 15(9), 642; https://doi.org/10.3390/insects15090642 - 26 Aug 2024

Viewed by 327

Abstract

(1) Background: Mitochondrial genomes have been extensively employed as a crucial marker in numerous dipteran families for understanding phylogenetics and systematics relations, thereby playing a pivotal role in molecular biology studies. The phylogenetic relationship of the Harnischia generic complex remains contentious due to [...] Read more.

(1) Background: Mitochondrial genomes have been extensively employed as a crucial marker in numerous dipteran families for understanding phylogenetics and systematics relations, thereby playing a pivotal role in molecular biology studies. The phylogenetic relationship of the Harnischia generic complex remains contentious due to the paucity of taxonomic and molecular data. Specifically, the evolutionary relationships among Cryptochironomus, Demicryptochironomus, and Harnischia are still unclear. (2) Methods: In this study, Polypedilum and Endochironomus were used as outgroups to analyze phylogenetic relationships among Cryptochironomus, Demicryptochironomus, and Harnischia, mitogenomes of four Cryptochironomus, two Demicryptochironomus, two Harnischia, and two Cladopelma were newly sequenced. Subsequently, we conducted a thorough analysis of the nucleotide composition, sequence length, and evolutionary rate. (3) Results: All mitogenomes exhibited structural conservation, with all genes consistently arranged in the identical order as that of the ancestral mitogenome. Nucleotide composition varied significantly among different genes, and the control region displayed the highest A + T content. All protein-coding genes undergo rigorous purification selection, with the ATP8 gene exhibiting the most rapid evolutionary rate among them. Utilizing Bayesian Inference (BI) and Maximum Likelihood (ML) methods across various databases, we reconstructed the phylogenetic relationships among the genera within the Harnischia generic complex, drawing insights from an analysis of 14 mitochondrial genomes. (4) Conclusions: Our results showed that the monophyly of the genera Harnischia was well supported in all topologies; Cryptochironomus is sister to Demicryptochironomus. Full article

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

► Show Figures

Figure 1

35 pages, 63762 KiB

Open AccessArticle

A Phenomenon: What Are the Minuscule Grey Moths Abundant in the Dry Season in the Tropical Dry Forests of the Pacific Coast of Honduras?

by Jonas R. Stonis, Andrius Remeikis, Arūnas Diškus, Viktorija Dobrynina and Svetlana Orlovskytė

Insects 2024, 15(9), 641; https://doi.org/10.3390/insects15090641 - 26 Aug 2024

Viewed by 287

Abstract

Our investigation centered on the tropical dry forests along the Pacific coast of Honduras, aiming to elucidate the presence and abundance of minuscule grey moths during the dry season. Through specimen dissections and the taxonomic identification of the collected material, we have described [...] Read more.

Our investigation centered on the tropical dry forests along the Pacific coast of Honduras, aiming to elucidate the presence and abundance of minuscule grey moths during the dry season. Through specimen dissections and the taxonomic identification of the collected material, we have described three new species: Acalyptris podenasi sp. nov., A. palpiformis sp. nov., and A. tortoris sp. nov. Additionally, we documented two species previously known from neighboring countries, A. lascuevella Puplesis & Robinson and A. basicornis Remeikis & Stonis. The females of A. lascuevella were previously unknown and are documented here for the first time. Morphological examinations were complemented by DNA barcoding, particularly highlighting variation in A. lascuevella. The paper’s primary significance lies not only in the description of new species but also in uncovering their taxonomic, morphological, and molecular importance. We found that these species are unique and indicative of the previously unstudied dry forests as a distinct ecosystem. Our findings revealed several novel atypical morphological traits within the studied Nepticulidae, including unusually large signum cells in the female genitalia, a dorso-ventrally divided uncus, and asymmetrical valvae in the male genitalia. These discoveries underscore the morphological diversity of Acalyptris Meyrick and their significance in evolutionary biology. Consequently, the paper addresses a previously unknown phenomenon of the occurrence and astonishing abundance of minuscule plant-mining micromoths in dry deciduous forests during the peak of the dry season. We hope that this paper will encourage Lepidoptera taxonomists to explore micromoths in other tropical dry forests, which, while limited in distribution, hold global importance. The paper is extensively illustrated with photographs of Acalyptris adults and their genitalia, along with maps, habitats, and molecular phylogenetic trees. Full article

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

► Show Figures

Figure 1

27 pages, 11103 KiB

Open AccessArticle

Resolving the Taxonomy of Mountain Syrphidae (Diptera) in the Iberian Peninsula: The Species Group of Cheilosia melanura Becker, 1894

by Iván Ballester-Torres, Zorica Nedeljković, Pablo Aguado-Aranda, Ante Vujić, María Ángeles Marcos-García and Antonio Ricarte

Insects 2024, 15(9), 640; https://doi.org/10.3390/insects15090640 - 26 Aug 2024

Viewed by 337

Abstract

The largest genus of Palaearctic Syrphidae, Cheilosia Meigen, 1822 (Syrphidae: Rhingiini), is currently under revision in the Ibero-Balearic region (Iberian Peninsula + Balearic Islands). Prior to this study, various species groups with putative phylogenetic support were defined for this genus of complex taxonomy. [...] Read more.

The largest genus of Palaearctic Syrphidae, Cheilosia Meigen, 1822 (Syrphidae: Rhingiini), is currently under revision in the Ibero-Balearic region (Iberian Peninsula + Balearic Islands). Prior to this study, various species groups with putative phylogenetic support were defined for this genus of complex taxonomy. The group of Cheilosia melanura Becker, 1894 includes species distributed all over Europe, with some of these species being similar each other in both morphology and genetics. After recent fieldwork in different Iberian localities and consultation of entomological collections, a new species from Sierra Nevada (Granada, Spain) was uncovered, described, and illustrated. Data on diagnostic characters, intraspecific variability, and adult biology were also provided. Maximum likelihood analyses of the fragment “C” of the 5′ end of the cytochrome c oxydase subunit I (COI-5′) and complete COI-5′ were performed to explore and support morphological species concepts within the group. The Spanish-endemic Cheilosia andalusiaca Torp Pedersen, 1971 is recognised here to be part of the C. melanura group based both on morphological and molecular evidence. Cheilosia carbonaria Egger, 1860 and Cheilosia cynocephala Loew, 1840 from the Iberian Peninsula are reported for the first time based on specimens originating in the Spanish Pyrenees. An identification key for the Iberian species of the C. melanura group is provided. Full article

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

► Show Figures

Figure 1

11 pages, 1204 KiB

Open AccessArticle

European Culex pipiens Populations Carry Different Strains of Wolbachia pipientis

by Tobias Lilja, Anders Lindström, Luis M. Hernández-Triana, Marco Di Luca and Olivia Wesula Lwande

Insects 2024, 15(9), 639; https://doi.org/10.3390/insects15090639 - 26 Aug 2024

Viewed by 342

Abstract

The mosquito Culex pipiens occurs in two ecotypes differing in their mating and overwintering behavior: pipiens mate in open environments and diapause, and molestus also mate in small spaces and is active throughout the year. Cx. pipiens carry Wolbachia endosymbionts of the w [...] Read more.

The mosquito Culex pipiens occurs in two ecotypes differing in their mating and overwintering behavior: pipiens mate in open environments and diapause, and molestus also mate in small spaces and is active throughout the year. Cx. pipiens carry Wolbachia endosymbionts of the wPip strain, but the frequency of infection differs between studied populations. Wolbachia infection affects the host reproductive success through cytoplasmic incompatibility. wPip Wolbachia is divided into five types, wPip I–V. The type of wPip carried varies among Cx. pipiens populations. In northern European locations different wPip types are found in the two ecotypes, whereas in southern locations, they often carry the same type, indicating differences in hybridization between ecotypes. In this study, Cx. pipiens specimens of both ecotypes were collected from Sweden and compared to specimens from Norway, England, Italy, and the Netherlands, as well as Cx. quinquefasciatus from Mali and Thailand. The abundance varied, but all specimens were infected by Wolbachia, while the tested specimens of other mosquito species were often uninfected. The wPip strains were determined through the sequence analysis of Wolbachia genes ank2 and pk1, showing that Cx. pipiens ecotypes in Scandinavia carry different wPip strains. The observed differences in wPip strains indicate that hybridization is not frequent and may contribute to barriers against hybridization of the ecotypes in Sweden and Norway. Full article

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

► Show Figures

Figure 1

8 pages, 1201 KiB

Open AccessArticle

Slit in a Nest Site Influences the Nest Site Selection in Cavity Nesting Ant Colonies

by Anna Gruszka, Mateusz Rolski, Mariia Marczak and Sławomir Mitrus

Insects 2024, 15(9), 638; https://doi.org/10.3390/insects15090638 - 26 Aug 2024

Viewed by 347

Abstract

For ants, nests provide a refuge against predators and protection from environmental factors. Thus, choosing a good nest site is important for an ant colony, but nest sites are limited resources. Ants of the genus Temnothorax inhabit small cavities in, e.g., acorns, twigs [...] Read more.

For ants, nests provide a refuge against predators and protection from environmental factors. Thus, choosing a good nest site is important for an ant colony, but nest sites are limited resources. Ants of the genus Temnothorax inhabit small cavities in, e.g., acorns, twigs and under rocks. Earlier, it was shown that the ants are able to choose a superior site. In this study, using binary choice tests, we studied the nest site selection by Temnothorax crassispinus ant colonies that typically inhabit empty acorns. For this purpose, we used artificial nest sites without and with an additional slit in the nest wall, mimicking the cracks in potential nest sites under natural conditions. We found that the ant colonies preferred artificial nest sites without these slits. However, no difference in the number of colonies inhabited nest sites with a slit vs. those without a slit was found when the slits were closed using transparent food foil, which prevented the air flow while keeping an inflow of light. What is more, additional light through the hole in the red filter covering the artificial nest sites had no influence on the nest site selection. The results of this study suggest that the air flow through a slit in the nest site wall, rather than additional light, influences the nest site selection. The absence of cracks, e.g., in acorns, could be an indication of the durability of potential nest sites. Thus, choosing a cavity without such damage could be beneficial for the ant colonies. Full article

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

► Show Figures

Figure 1

12 pages, 2232 KiB

Open AccessArticle

Physiological Status of Rice Leaf-Roller Cnaphalocrocis medinalis (Lepidoptera: Crambidae) Adults Trapped by Sex Pheromone and Floral Odor

by Jianfei Lu, Xiaoming Yao, Ying Shen, Caroline Du, Qianshuang Guo and Yongjun Du

Insects 2024, 15(9), 637; https://doi.org/10.3390/insects15090637 - 25 Aug 2024

Viewed by 425

Abstract

The rice leaf-roller Cnaphalocrocis medinalis is an important migratory pest of rice. We conducted a study to determine the physiological status of adults trapped by a sex pheromone and floral odor. In the immigrant group, the number of males trapped by the floral [...] Read more.

The rice leaf-roller Cnaphalocrocis medinalis is an important migratory pest of rice. We conducted a study to determine the physiological status of adults trapped by a sex pheromone and floral odor. In the immigrant group, the number of males trapped by the floral odor was greater than the number caught by sex pheromone trapping. The volume of testes was similar in the above two trapping methods but was smaller than in the sweep net method. The ovary developmental grade, mating rate, and number of matings of females caught in floral odor trap were higher than in those caught in the sweep net. In the local breeding group, the number of males trapped by sex pheromones was greater than the number trapped by the floral odor. The volume of testes was smaller in the floral odor trap compared to the pheromone trap group, with the largest in the sweep net group. The ovarian developmental grade, mating rate, and number of matings of females were significantly higher in the floral odor trap group than in the sweep net group. In the emigrant group, the adult olfactory response to the sex pheromone and floral odor was low. The volume of testes was larger in the sweep net group compared to the moths caught by floral odor trapping. The number of eggs laid by female immigrants trapped by the floral odor and sweep net was similar, while the number in the local breeding group was greater in moths caught with the sweep net in comparison with those caught by the floral odor trap. The difference in egg hatchability between the two trapping methods in both immigrants and local breedings was not significant. Full article

(This article belongs to the Special Issue Recent Advances in Migrant Insect Pests)

► Show Figures

Figure 1

12 pages, 4643 KiB

Open AccessArticle

New Genus and Species of Webspinners (Insecta: Embioptera) from the Mid-Cretaceous of Myanmar with a Catalog of Fossil Members

by Siting Liu, Zihao Peng, Chaofan Shi, Dong Ren and Qiang Yang

Insects 2024, 15(9), 636; https://doi.org/10.3390/insects15090636 - 25 Aug 2024

Viewed by 369

Abstract

One new genus (Ocrognethoda gen. nov.) and three new species of webspinners (Ocrognethoda olivea gen. et sp. nov., Gnethoda lata sp. nov. and Parasorellembia hamata sp. nov.) are described from the Upper Cretaceous of Myanmar amber. Ocrognethoda olivea gen. et sp. [...] Read more.

One new genus (Ocrognethoda gen. nov.) and three new species of webspinners (Ocrognethoda olivea gen. et sp. nov., Gnethoda lata sp. nov. and Parasorellembia hamata sp. nov.) are described from the Upper Cretaceous of Myanmar amber. Ocrognethoda olivea gen. et sp. nov. and Gnethoda lata sp. nov. are attributed to the family Clothodidae due to their simplified and symmetrical male terminalia, in which the tenth tergum is undivided. Parasorellembia hamata sp. nov. is classified in the family Scelembiidae by a specialized abdominal apex: fused cerci, a broad right hemitergite of the tenth abdominal tergite, and ocelli presence. Moreover, based on the discovery of new genus and species, the male terminalia of Clothodidae and Sorellembiinae are briefly discussed. Full article

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

► Show Figures

Figure 1

14 pages, 2612 KiB

Open AccessArticle

The Growth Performance and Nutrient Composition of Black Soldier Fly (Hermetia illucens) Larvae Fed Slaughtered Bovine Blood

by Hao Bian, Yuting Qiao, Yantong Li, Zifan Wang, Lei Zhao, Zhiqiang Li, Bo Cheng and Gongtao Ding

Insects 2024, 15(9), 635; https://doi.org/10.3390/insects15090635 - 25 Aug 2024

Viewed by 539

Abstract

The disposal of slaughterhouse blood poses significant environmental challenges due to its biological instability and high nutrient content. We used a gradient of 10% blood increments (0–100%) to feed BSFL, and the correlation between the proportion of bovine blood and the BSFL weight [...] Read more.

The disposal of slaughterhouse blood poses significant environmental challenges due to its biological instability and high nutrient content. We used a gradient of 10% blood increments (0–100%) to feed BSFL, and the correlation between the proportion of bovine blood and the BSFL weight gain, mortality rate, fatty acid content, and amino acid content was researched. Results indicate a positive correlation between the bovine blood content and BSFL mortality, with survival rates above 95% for blood proportions below 60%. Larval weight exhibited a negative correlation as the bovine blood content increased. Nutritional analysis revealed that the crude protein content in BSFL increased proportionally with bovine blood (14.75–25.45 g/100 g), while the crude fat content decreased correspondingly (10.70–4.66 g/100 g). The sugar content remained relatively constant across groups. Fatty acid analysis showed increased levels of C16:0, C14:0, and C16:1 and decreased levels of C18:1, C18:2, and C18:3 with higher bovine blood contents. The amino acid content generally increased with higher blood proportions. This study highlights the bioconversion potential of BSFL for bovine blood and underscores the impact of protein, lipid, and sugar concentrations in feed on BSFL growth. These findings provide valuable insights for utilizing slaughterhouse waste in BSFL rearing, contributing to the development of more sustainable waste management and animal feed production methods. Full article

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

► Show Figures

Figure 1

11 pages, 884 KiB

Open AccessArticle

Olfactory Response of Sitophilus zeamais Adults to Odours of Semolina Pasta and Semolina Pasta Enriched with Different Amounts of Acheta domesticus Powder

by Pasquale Trematerra, Marco Colacci, Maria Cristina Messia, Maria Carmela Trivisonno, Anna Reale, Floriana Boscaino and Giacinto Salvatore Germinara

Insects 2024, 15(9), 634; https://doi.org/10.3390/insects15090634 - 25 Aug 2024

Viewed by 465

Abstract

The behavioural response of adult maize weevil, Sitophilus zeamais, to different types of semolina pasta enriched or not enriched with increasing proportions (5%, 10%, and 15%) of house cricket (Acheta domesticus) powder was investigated in olfactometer arena bioassays by using [...] Read more.

The behavioural response of adult maize weevil, Sitophilus zeamais, to different types of semolina pasta enriched or not enriched with increasing proportions (5%, 10%, and 15%) of house cricket (Acheta domesticus) powder was investigated in olfactometer arena bioassays by using trap devices. In the five-choice behavioural bioassays, the number of S. zeamais adults attracted to 100% durum wheat semolina pasta was significantly higher than those attracted to the other pasta types enriched with A. domesticus powder. In the two-choice behavioural bioassays, the Response Index for each pasta type was positive and significant. However, although not significant, there was a progressive reduction in the Response Index as the cricket powder content increased. In similar experiments, there were no significant differences between cricket powder alone and the control in the number of attracted S. zeamais, indicating a neutral effect towards insects. These observations suggest that the lower attractiveness of pasta enriched with house cricket powder is mainly due to the masking of host food odours. Solid-phase microextraction coupled to gas chromatography–mass spectroscopy identified a total of 18 compounds in the head-space samples of the different types of pasta, highlighting differences in volatile composition. Some volatile compounds were only present in the pasta produced with cricket powder. In particular, 1-octen-3-ol and phenol were present in the samples containing 5%, 10%, or 15% cricket powder; pentanal, benzaldehyde, and dimethyl disulphide were present in samples containing 10% or 15% cricket powder; and 2,5-dimethyl-pyrazine was present in the sample containing 15% cricket powder. Further investigation with individual compounds and mixtures is needed to define the chemical basis of the differences in the insect olfactory preference observed in this study. Full article

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

► Show Figures

Figure 1

13 pages, 747 KiB

Open AccessArticle

Functional and Numerical Responses of Harmonia axyridis (Coleoptera: Coccinellidae) to Rhopalosiphum nymphaeae (Hemiptera: Aphididae) and Their Potential for Biological Control

by Chong Li, Jingya Yu, Runping Mao, Kaili Kang, Letian Xu and Mengting Wu

Insects 2024, 15(9), 633; https://doi.org/10.3390/insects15090633 - 23 Aug 2024

Viewed by 373

Abstract

The water lily aphid (Rhopalosiphum nymphaeae) is a highly polyphagous herbivore that causes severe damage to many terrestrial and aquatic plants, especially lotus. Due to environmental concerns about water pollution and other issues caused by chemical control methods, there is an [...] Read more.

The water lily aphid (Rhopalosiphum nymphaeae) is a highly polyphagous herbivore that causes severe damage to many terrestrial and aquatic plants, especially lotus. Due to environmental concerns about water pollution and other issues caused by chemical control methods, there is an urgent need to develop effective and sustainable control methods. The harlequin ladybird (Harmonia axyridis) is a well-known aphid predator and may pose a potential threat to R. nymphaeae. To study the predation ability of H. axyridis at different developmental stages on R. nymphaeae, we assessed the functional response, attack rate, and search effect of H. axyridis larvae and adults preying on R. nymphaeae. The numerical response of this process was also evaluated under a constant ladybird-to-aphid ratio and constant aphid density conditions, respectively. Our results showed that all predator stages exhibited type II functional responses. The predation rate of individual H. axyridis on R. nymphaeae nymphs significantly increased as prey density increased. In contrast, the search effect of H. axyridis gradually decreased with an increase in prey density. Meanwhile, H. axyridis at different developmental stages possess varying predation abilities; fourth instar and adult H. axyridis were found to be highly efficient predators of R. nymphaeae. H. axyridis adults exhibited the highest predation ability and predation rate, while both the adult and fourth-instar larvae exhibited the highest attack rate. Moreover, fourth-instar larvae exhibited the highest search effect value at initially lower prey densities, although adults surpassed them at higher prey densities. Our results also indicated that H. axyridis exhibited varying degrees of intraspecific interference and self-interference influence as predator density increases. These results strongly support H. axyridis as an effective biocontrol agent for R. nymphaeae. Full article

(This article belongs to the Special Issue Genetics and Evolution of Ladybird Beetles in Biological Control)

► Show Figures

Figure 1

22 pages, 341 KiB

Open AccessArticle

Use of Periplaneta americana as a Soybean Meal Substitute: A Step towards Sustainable Transformative Poultry Feeds

by Farwa Mustafa, Asif Sajjad, Roughaina Tahir, Mudssar Ali, Muhammad Sajjad, Asim Abbasi, Ehsaan Ullah Khan, Saba Zafar, Abeer Hashem, Graciela Dolores Avila-Quezada and Elsayed Fathi Abd_Allah

Insects 2024, 15(9), 632; https://doi.org/10.3390/insects15090632 - 23 Aug 2024

Viewed by 390

Abstract

Insects are becoming increasingly popular as a sustainable and nutritious alternative protein source in poultry feeds, due to their high protein content, low environmental impact, and efficient feed conversion rates. Using insect-based feeds can reduce the need for traditional protein sources like soybean [...] Read more.

Insects are becoming increasingly popular as a sustainable and nutritious alternative protein source in poultry feeds, due to their high protein content, low environmental impact, and efficient feed conversion rates. Using insect-based feeds can reduce the need for traditional protein sources like soybean meal (SBM), which often contribute to environmental issues such as deforestation and high water consumption. The current experiments were devised to assess the impacts of the partial replacement of SBM with the American cockroach Periplaneta americana and black soldier fly Hermetia illucens on the performances, hematology, gut morphometry, and meat quality of male broilers (Ross 308). A total of 350, 1-day-old chicks weighing 40.05 ± 0.27 g were divided into 7 dietary treatments (5 pens/treatment and 10 birds/pen) at random, i.e., a 4, 8, or 12% SMB replacement with P. americana and H. illucens. Soybean meal was used as a basal diet and taken as a control. The results indicated that broilers fed on 12% P. americana or H. illucens showed significant improvements (p < 0.05) in feed conversion ratio, live weight, and daily weight gain. Hematological traits significantly improved (p < 0.05). A gut histology showed increased villus height, villus width, crypt depth, and villus height/crypt depth ratios, indicating improved nutrient absorption. Broiler meat fed on 12% P. americana meal had significantly higher redness and yellowness (p < 0.05). Substituting soybean meal with up to 12% P. americana or H. illucens meal in poultry feed can enhance the broilers’ growth performance, hematology, gut morphometry, and meat quality. Hence, these findings imply that P. americana or H. illucens meal are viable and constructive alternative protein sources in poultry nutrition, offering a sustainable approach to meet the increasing demand for animal protein across the world. Full article

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

Journal Menu

Journal Browser

Insects, Volume 15, Issue 9 (September 2024) – 29 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI