Insects

14 pages, 2650 KiB

Open AccessArticle

A Genetic Compensation Phenomenon and Global Gene Expression Changes in Sex-miR-2766-3p Knockout Strain of Spodoptera exigua Hübner (Lepidoptera: Noctuidae)

by Yayun Zuo, Zeyu Wang, Xuan Ren, Yakun Pei, Ahmed A. A. Aioub and Zhaonong Hu

Insects 2022, 13(11), 1075; https://doi.org/10.3390/insects13111075 - 21 Nov 2022

Cited by 3 | Viewed by 1997

Abstract

MicroRNAs (miRNAs) drive the post-transcriptional repression of target mRNAs and play important roles in a variety of biological processes. miR-2766-3p is conserved and abundant in Lepidopteran species and may be involved in a variety of biological activities. In this study, Sex-miR-2766-3p was predicted [...] Read more.

MicroRNAs (miRNAs) drive the post-transcriptional repression of target mRNAs and play important roles in a variety of biological processes. miR-2766-3p is conserved and abundant in Lepidopteran species and may be involved in a variety of biological activities. In this study, Sex-miR-2766-3p was predicted to potentially bind to the 3′ untranslated region (UTR) of cap ‘n’ collar isoform C (CncC) in Spodoptera exigua, and Sex-miR-2766-3p was confirmed to regulate the expression of SeCncC through screening with a luciferase reporter system. Although CRISPR/Cas9 has been extensively utilized to examine insect gene function, studies of miRNA function are still relatively uncommon. Thus, we employed CRISPR/Cas9 to knock out Sex-miR-2766-3p from S. exigua. However, the expression of SeCncC was not significantly altered in the knockout strain (2766-KO) compared with that of the WHS strain. This result suggested that a miRNA knockout might lack phenotypes because of genetic robustness. Additionally, we used transcriptome analysis to examine how the global gene expression patterns of the Sex-miR-2766-3p knockout strain varied. RNA-seq data revealed 1746 upregulated and 2183 downregulated differentially expressed genes (DEGs) in the 2766-KO strain, which might be the result of Sex-miR-2766-3p loss or DNA lesions as the trigger for transcriptional adaptation. GO function classification and KEGG pathway analyses showed that these DEGs were enriched for terms related to binding, catalytic activity, metabolic process, and signal transduction. Our findings demonstrated that S. exigua could compensate for the missing Sex-miR-2766-3p by maintaining the expression of SeCncC by other pathways. Full article

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

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12 pages, 9218 KiB

Open AccessArticle

Ultrastructure of Ejaculatory Ducts of Cerapanorpa nanwutaina and Furcatopanorpa longihypovalva (Mecoptera: Panorpidae)

by Qi-Hui Lyu, Qing-Xiao Chen, Ya-Lan Sun and Wen-Jie Dong

Insects 2022, 13(11), 1074; https://doi.org/10.3390/insects13111074 - 21 Nov 2022

Viewed by 2446

Abstract

The ultrastructure of the ejaculatory duct was investigated in the scorpionflies Cerapanorpa nanwutaina (Chou 1981) and Furcatopanorpa longihypovalva (Hua & Cai, 2009) (Mecoptera: Panorpidae) using light and transmission electron microscopy. The ejaculatory ducts of both species comprise a median duct and an accessory [...] Read more.

The ultrastructure of the ejaculatory duct was investigated in the scorpionflies Cerapanorpa nanwutaina (Chou 1981) and Furcatopanorpa longihypovalva (Hua & Cai, 2009) (Mecoptera: Panorpidae) using light and transmission electron microscopy. The ejaculatory ducts of both species comprise a median duct and an accessory sac. The median duct consists of a basal lamina, a mono-layered epithelium, a subcuticular cavity, and an inner cuticle. The accessory sac contains a single layer of epithelium and a basal lamina. A muscular layer is present in the accessory sac of C. nanwutaina and in the median duct of F. longihypovalva. The epithelia in the median duct and the accessory sac are well developed, their cells containing numerous cisterns of rough endoplasmic reticulum, mitochondria, and microvilli. The secretions of the median duct are first extruded into the subcuticular cavity and then into the lumen through an inner cuticle, while the secretions of the accessory sac are discharged directly into the lumen. The ejaculatory duct of F. longihypovalva is longer and has thicker epithelium with more cell organelles and secretions than that of C. nanwutaina. Full article

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

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17 pages, 3322 KiB

Open AccessFeature PaperArticle

Combined Jasmonic Acid and Ethylene Treatment Induces Resistance Effect in Faba Bean Plants Against Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)

by Yu-Lian Jia, Tao Zhang, Jun-Rui Zhi, Lu Tuo, Wen-Bo Yue, Ding-Yin Li and Li Liu

Insects 2022, 13(11), 1073; https://doi.org/10.3390/insects13111073 - 21 Nov 2022

Cited by 3 | Viewed by 2094

Abstract

Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a serious invasive pest in China. In this study, we determined whether exogenous jasmonic acid (JA) and ethylene (ET) treatments could induce resistance against F. occidentalis in faba bean plants. First, we investigated the effects of different [...] Read more.

Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a serious invasive pest in China. In this study, we determined whether exogenous jasmonic acid (JA) and ethylene (ET) treatments could induce resistance against F. occidentalis in faba bean plants. First, we investigated the effects of different concentrations of JA or ET alone on F. occidentalis and then assessed the effects of optimal concentrations of JA and ET combined. Our results showed that the optimal concertation of JA was 2 mmol/L and ET was 0.5 mmol/L. JA + ET mixture showed the greatest inhibitory effect in terms of oviposition and feeding. JA with ET was found to induce changes in the activities of lipoxygenase (LOX), allene oxide synthase (AOS), polyphenol oxidase (PPO), 1-aminocyclopropane 1-carboxylic acid synthase (ACS), and trypsin inhibitor (TI). This treatment also activated or inhibited the relative expression levels of LOX1, ACO2, ACS2, and AP2/ERF. Treatment of faba bean plants with JA and ET significantly prolonged F. occidentalis development and adult preoviposition period, significantly reduced per-female oviposition, and altered male longevity and offspring demographic parameters. These results indicate that JA with ET can induce defenses against the growth and development of F. occidentalis in faba bean plants. Full article

(This article belongs to the Special Issue Arthropod Interactions and Pest Management in Fruit and Vegetable Crops)

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13 pages, 2996 KiB

Open AccessArticle

Silencing of dre4 Contributes to Mortality of Phyllotreta striolata

by Dongping Chen, Ru Yan, Zhanyi Xu, Jiali Qian, Yinfang Yu, Shunshun Zhu, Huiming Wu, Guonian Zhu and Mengli Chen

Insects 2022, 13(11), 1072; https://doi.org/10.3390/insects13111072 - 20 Nov 2022

Cited by 5 | Viewed by 2265

Abstract

The striped flea beetle, Phyllotreta striolata, is one of the most destructive pests of Cruciferae crops worldwide. RNA interference (RNAi) is a promising alternative strategy for pest biological control, which overcomes the weakness of synthetic insecticides, such as pest resistance, food safety problems [...] Read more.

The striped flea beetle, Phyllotreta striolata, is one of the most destructive pests of Cruciferae crops worldwide. RNA interference (RNAi) is a promising alternative strategy for pest biological control, which overcomes the weakness of synthetic insecticides, such as pest resistance, food safety problems and toxicity to non-target insects. The homolog of Spt16/FACT, dre4 plays a critical role in the process of gene transcription, DNA repair, and DNA replication; however, the effects of dre4 silencing in P. striolata remain elusive. In this study, we cloned and characterized the full-length dre4 from P. striolata and silenced Psdre4 through microinjection and oral delivery; it was found that the silencing of dre4 contributed to the high mortality of P. striolata in both bioassays. Moreover, 1166 differentially regulated genes were identified after Psdre4 interference by RNA-seq analysis, which might have been responsible for the lethality. The GO analysis indicated that the differentially regulated genes were classified into three GO functional categories, including biological process, cellular component, and molecular function. The KEGG analysis revealed that these differentially regulated genes are related to apoptosis, autophagy, steroid hormone biosynthesis, cytochrome P450 and other signaling pathways. Our results suggest that Psdre4 is a fatal RNAi target and has significant potential for the development of RNA pesticides for P. striolata management. Full article

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16 pages, 1484 KiB

Open AccessArticle

A Non-Invasive Method of Estimating Populations of Tomicus Piniperda on Scots Pine (Pinus Sylvestris L.)

by Karol Zubek, Joanna Czerwik-Marcinkowska and Andrzej Borkowski

Insects 2022, 13(11), 1071; https://doi.org/10.3390/insects13111071 - 20 Nov 2022

Viewed by 1465

Abstract

The fully non-invasive method presented here can be used to evaluate Tomicus piniperda L. population sizes in areas subject to strict protection. Data were collected in 2021–2022 in forests containing P. sylvestris, with different stand structures, in the Suchedniowsko-Oblęgorski Landscape Park, Poland. [...] Read more.

The fully non-invasive method presented here can be used to evaluate Tomicus piniperda L. population sizes in areas subject to strict protection. Data were collected in 2021–2022 in forests containing P. sylvestris, with different stand structures, in the Suchedniowsko-Oblęgorski Landscape Park, Poland. Entomological analyses were carried out on natural traps made from live uncolonised trees. Stepwise regression was used to describe the size of T. piniperda populations. From a set of features representing stem colonisation parameters, stem traits and habitat, the following had a significant effect (p < 0.05) on the total number of galleries of T. piniperda on stems: (1) the number of T. piniperda maternal tunnels in the sixth stem section covering 2.5% of the total length, (2) the length of the stem section with bark thickness greater than 7 mm, and (3) stand structure (homogeneous Scots pine stands). The model can explain 93%

(R_{a d j}^{2} = 0.9333)

of the variability in the total number of T. piniperda galleries on trap trees. The mean relative error of estimation is 20.1%. The proposed method is particularly valuable in a climate context. The data obtained enable the prediction of the direct effects of climate change on the population dynamics of T. piniperda in natural forests. Full article

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

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21 pages, 4985 KiB

Open AccessArticle

Anopheles gambiae Trehalase Inhibitors for Malaria Vector Control: A Molecular Docking and Molecular Dynamics Study

by Eunice O. Adedeji, Gbolahan O. Oduselu, Olubanke O. Ogunlana, Segun Fatumo, Rainer Koenig and Ezekiel Adebiyi

Insects 2022, 13(11), 1070; https://doi.org/10.3390/insects13111070 - 19 Nov 2022

Cited by 8 | Viewed by 2389

Abstract

Trehalase inhibitors are considered safe alternatives for insecticides and fungicides. However, there are no studies testing these compounds on Anopheles gambiae, a major vector of human malaria. This study predicted the three-dimensional structure of Anopheles gambiae trehalase (AgTre) and identified potential [...] Read more.

Trehalase inhibitors are considered safe alternatives for insecticides and fungicides. However, there are no studies testing these compounds on Anopheles gambiae, a major vector of human malaria. This study predicted the three-dimensional structure of Anopheles gambiae trehalase (AgTre) and identified potential inhibitors using molecular docking and molecular dynamics methods. Robetta server, C-I-TASSER, and I-TASSER were used to predict the protein structure, while the structural assessment was carried out using SWISS-MODEL, ERRAT, and VERIFY3D. Molecular docking and screening of 3022 compounds was carried out using AutoDock Vina in PyRx, and MD simulation was carried out using NAMD. The Robetta model outperformed all other models and was used for docking and simulation studies. After a post-screening analysis and ADMET studies, uniflorine, 67837201, 10406567, and Compound 2 were considered the best hits with binding energies of −6.9, −8.9, −9, and −8.4 kcal/mol, respectively, better than validamycin A standard (−5.4 kcal/mol). These four compounds were predicted to have no eco-toxicity, Brenk, or PAINS alerts. Similarly, they were predicted to be non-mutagenic, carcinogenic, or hepatoxic. 67837201, 10406567, and Compound 2 showed excellent stability during simulation. The study highlights uniflorine, 67837201, 10406567, and Compound 2 as good inhibitors of AgTre and possible compounds for malaria vector control. Full article

(This article belongs to the Special Issue Controlling Mosquitoes to Reduce the Spread of Mosquito-Borne Diseases)

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15 pages, 1657 KiB

Open AccessArticle

New Distributional Records and Characterization of the Climatic Niche of Lepturges (Lepturges) limpidus Bates, 1872 (Coleoptera, Cerambycidae): Sink or Source Population?

by Néstor G. Valle and Marianna V. P. Simões

Insects 2022, 13(11), 1069; https://doi.org/10.3390/insects13111069 - 18 Nov 2022

Cited by 2 | Viewed by 2024

Abstract

A growing number of cases of the spread and establishment of non-native species outside their previously known ranges has been reported in recent years. Here we report new distributional records of Lepturges (Lepturges) limpidus Bates, 1872 (Cerambycidae) from Argentina and investigate [...] Read more.

A growing number of cases of the spread and establishment of non-native species outside their previously known ranges has been reported in recent years. Here we report new distributional records of Lepturges (Lepturges) limpidus Bates, 1872 (Cerambycidae) from Argentina and investigate whether these records could represent established populations. We constructed ellipsoid envelope models to characterize climatic niches of L. limpidus, identified areas of climatic suitability, investigated the status of new records as climatic outliers, and evaluated its dependency on its known hostplant as a limiting factor for the beetle distribution. Results indicate widespread climatic suitability in the Neotropical Region, and new records are not outliers with regard to the climatic profile of L. limpidus. Association with its known hostplant is non-dependent, indicating that the species might utilize different hosts plants. New records likely represent established populations, but targeted surveys should be carried out to detect new arrivals and enable the installation of mitigation and control measures. Full article

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

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13 pages, 433 KiB

Open AccessReview

Post-Harvest Insect Pests and Their Management Practices for Major Food and Export Crops in East Africa: An Ethiopian Case Study

by Muez Berhe, Bhadriraju Subramanyam, Mekasha Chichaybelu, Girma Demissie, Fetien Abay and Jagger Harvey

Insects 2022, 13(11), 1068; https://doi.org/10.3390/insects13111068 - 18 Nov 2022

Cited by 13 | Viewed by 6353

Abstract

Ethiopian subsistence farmers traditionally store their grain harvests, leaving them open to storage pests and fungi that can cause contamination of major staple crops. Applying the most effective strategy requires a precise understanding of the insect species, infestation rates, storage losses, and storage [...] Read more.

Ethiopian subsistence farmers traditionally store their grain harvests, leaving them open to storage pests and fungi that can cause contamination of major staple crops. Applying the most effective strategy requires a precise understanding of the insect species, infestation rates, storage losses, and storage conditions in the various types of farmers’ grain stores. This study did a complete literature analysis on post-harvest pest and management measures with a focus on Ethiopia. The most frequent insect pests of stored cereals in this study were weevils (Sitophilus spp.), the lesser grain borer (Rhyzopertha dominica), rust-red flour beetle (Tribolium sp.), sawtoothed grain beetle (Oryzaephilus sp.), grain beetle (Cryptolestes spp.), Indian meal moth (Plodia interpunctella), and Angoumois grain moth (Sitotroga cerealella). Flour beetles (Tribolium spp.), sawtoothed beetles (Oryzaephilus sp.), flat grain beetles (Cryptolestes pusillus), and some moths have been identified as common stored product pests of stored oil seed, while bruchid beetles (Callosobruchus chinensis) and the moths were reported for pulses. Additionally, the storage pests in Ethiopia under varied conditions caused storage losses of 9–64.5%, 13–95%, 36.9–51.9%, and 2–94.7% in maize, sorghum, chickpeas, and sesame, respectively. To reduce the losses incurred, preventative measures can be taken before infestations or as soon as infestations are discovered. A variety of pest population monitoring systems for harvested products and retailers have been developed and recommended. In this context, reducing post-harvest grain losses is an urgent concern for improving food accessibility and availability for many smallholder farmers in Ethiopia and ensuring the nation’s long-term food security. Full article

(This article belongs to the Collection Stored-Product Pests: Biology, Ecology, Behavior and Integrated Management)

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11 pages, 523 KiB

Open AccessFeature PaperArticle

Generic Pheromones Identified from Northern Hemisphere Cerambycidae (Coleoptera) Are Attractive to Native Longhorn Beetles from Central-Southern Chile

by Tomislav Curkovic, Diego Arraztio, Amanda Huerta, Ramón Rebolledo, Arly Cheuquel, Américo Contreras and Jocelyn G. Millar

Insects 2022, 13(11), 1067; https://doi.org/10.3390/insects13111067 - 18 Nov 2022

Cited by 3 | Viewed by 2056

Abstract

We conducted field bioassays with several known cerambycid pheromones in two zones of central-southern Chile: (1) Las Trancas (Ñuble region) and Coñaripe (Los Rios region) (Study 1) and (2) Rucamanque and Maquehue (La Araucania region) (Study 2). Up to eight compounds were tested [...] Read more.

We conducted field bioassays with several known cerambycid pheromones in two zones of central-southern Chile: (1) Las Trancas (Ñuble region) and Coñaripe (Los Rios region) (Study 1) and (2) Rucamanque and Maquehue (La Araucania region) (Study 2). Up to eight compounds were tested individually, including 3-hydroxy-2-hexanone, (2R*,3S*)- and (2R*,3R*)-2,3-hexanediol, fuscumol, fuscumol acetate, monochamol, 2-methylbutanol, and geranylacetone. Compounds were loaded in plastic sachets placed in either multiple funnel or cross-vane panel traps hung in trees in a randomized block design (n = 3 or 4). The number of treatments and bioassay periods varied depending on the study. A total of 578 specimens belonging to 11 native species were collected, with the three captured in the highest numbers being Eryphus laetus (292 specimens), Calydon submetallicum (n = 234), and Chenoderus testaceus (n = 20). The three species are of economic importance: E. laetus is considered a minor pest in apple orchards, and the other two species infest Nothophagus hosts, including some timber species. Traps baited with 3-hydroxy-2-hexanone collected significant numbers of both sexes of the two most abundant species, and this compound was the only treatment that attracted C. submetallicum. (2R*,3R*)- and (2R*,3S*)-2,3-Hexanediols were also significantly attractive to E. laetus. Our results suggested that 3-hydroxy-2-hexanone and 2,3-hexanediols, which are known pheromone components of cerambycid species worldwide, are also likely to be conserved aggregation pheromone components among some species in western South America. Full article

(This article belongs to the Special Issue From Insect Pheromones to Mating Disruption: Theory and Practice (Volume II))

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13 pages, 2434 KiB

Open AccessArticle

Epidemiological, Entomological, and Climatological Investigation of the 2019 Dengue Fever Outbreak in Gewane District, Afar Region, North-East Ethiopia

by Wondemeneh Mekuriaw, Solomon Kinde, Bezabih Kindu, Yibeyin Mulualem, Girma Hailu, Araya Gebresilassie, Chalachw Sisay, Fitsum Bekele, Hiwot Amare, Mesfin Wossen, Adugna Woyessa, Chad L. Cross and Louisa A. Messenger

Insects 2022, 13(11), 1066; https://doi.org/10.3390/insects13111066 - 18 Nov 2022

Cited by 7 | Viewed by 3916

Abstract

Dengue Fever (DF) is an important arthropod-borne viral infection that has repeatedly occurred as outbreaks in eastern and northeastern Ethiopia since 2013. A cross-sectional epidemiological outbreak investigation was carried out from September to November 2019 on febrile patients (confirmed malaria negative) who presented [...] Read more.

Dengue Fever (DF) is an important arthropod-borne viral infection that has repeatedly occurred as outbreaks in eastern and northeastern Ethiopia since 2013. A cross-sectional epidemiological outbreak investigation was carried out from September to November 2019 on febrile patients (confirmed malaria negative) who presented with suspected and confirmed DF at both public and private health facilities in Gewane District, Afar Region, northeastern Ethiopia. Entomological investigation of containers found in randomly selected houses belonging to DF-positive patients was undertaken to survey for the presence of Aedes larvae/pupae. A total of 1185 DF cases were recorded from six health facilities during the 3-month study period. The mean age of DF cases was 27.2 years, and 42.7% of cases were female. The most affected age group was 15–49 years old (78.98%). The total case proportions differed significantly across age groups when compared to the population distribution; there were approximately 15% and 5% higher case proportions among those aged 15–49 years and 49+ years, respectively. A total of 162 artificial containers were inspected from 62 houses, with 49.4% found positive for Aedes aegypti larva/pupae. Aedes mosquitoes were most commonly observed breeding in plastic tanks, tires, and plastic or metal buckets/bowls. World Health Organization entomological indices classified the study site as high risk for dengue virus outbreaks (House Index = 45.2%, Container Index = 49.4%, and Breteau Index = 129). Time series climate data, specifically rainfall, were found to be significantly predictive of AR (p = 0.035). Study findings highlight the importance of vector control to prevent future DF outbreaks in the region. The scarcity of drinking water and microclimatic conditions may have also contributed to the occurrence of this outbreak. Full article

(This article belongs to the Special Issue Controlling Mosquitoes to Reduce the Spread of Mosquito-Borne Diseases)

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14 pages, 338 KiB

Open AccessEditor’s ChoiceReview

Competition: A Missing Component of Fruit Fly (Diptera: Tephritidae) Risk Assessment and Planning

by Anthony R. Clarke and Penelope F. Measham

Insects 2022, 13(11), 1065; https://doi.org/10.3390/insects13111065 - 17 Nov 2022

Cited by 9 | Viewed by 2734

Abstract

Tephritid fruit flies are internationally significant pests of horticulture. Because they are also highly invasive and of major quarantine concern, significant effort is placed in developing full or partial pest risk assessments (PRAs) for fruit flies, while large investments can be made for [...] Read more.

Tephritid fruit flies are internationally significant pests of horticulture. Because they are also highly invasive and of major quarantine concern, significant effort is placed in developing full or partial pest risk assessments (PRAs) for fruit flies, while large investments can be made for their control. Competition between fruit fly species, driven by the need to access and utilise fruit for larval development, has long been recognised by researchers as a fundamental component of fruit fly biology, but is entirely absent from the fruit fly PRA literature and appears not be considered in major initiative planning. First presenting a summary of the research data which documents fruit fly competition, this paper then identifies four major effects of fruit fly competition that could impact a PRA or large-scale initiative: (i) numerical reduction of an existing fruit fly pest species following competitive displacement by an invasive fruit fly; (ii) displacement of a less competitive fruit fly pest species in space, time or host; (iii) ecological resistance to fruit fly invasion in regions already with competitively dominant fruit fly species; and (iv) lesser-pest fruit fly resurgence following control of a competitively superior species. From these four major topics, six more detailed issues are identified, with each of these illustrated by hypothetical, but realistic biosecurity scenarios from Australia/New Zealand and Europe. The scenarios identify that the effects of fruit fly competition might both positively or negatively affect the predicted impacts of an invasive fruit fly or targeted fruit fly control initiative. Competition as a modifier of fruit fly risk needs to be recognised by policy makers and incorporated into fruit fly PRAs and major investment initiatives. Full article

(This article belongs to the Special Issue Tephritid Fruit Flies (Diptera: Tephritidae): Biology, Ecology, and Integrated Management)

7 pages, 1047 KiB

Open AccessArticle

A New Genus and Species of the Suborder Trogiomorpha (Insecta, Psocodea) from Mid-Cretaceous Amber of Myanmar

by Xinyi Zhang, Feiyang Liang and Xingyue Liu

Insects 2022, 13(11), 1064; https://doi.org/10.3390/insects13111064 - 17 Nov 2022

Cited by 3 | Viewed by 1664

Abstract

We established a new genus with a new species Brachyantennum spinosum Liang et Liu, gen. et sp. nov. from mid-Cretaceous Burmese Kachin amber. It is tentatively placed into the suborder Trogiomorpha, based on the strong external valve, the reduced dorsal and ventral valve, [...] Read more.

We established a new genus with a new species Brachyantennum spinosum Liang et Liu, gen. et sp. nov. from mid-Cretaceous Burmese Kachin amber. It is tentatively placed into the suborder Trogiomorpha, based on the strong external valve, the reduced dorsal and ventral valve, and the short subgenital plate covering the basal part of the external valve. This new genus is apparently close to the family Cormopsocidae, based on the well-developed and very long hindwing Sc vein. However, its familial placement is ambiguous and it can be excluded from the established families of Trogiomorpha by the presence of the tarsal ctenidiobothria on the mid- and hindleg. Full article

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

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17 pages, 1357 KiB

Open AccessFeature PaperArticle

Newly Discovered Components of Dendrolimus pini Sex Pheromone

by Krzysztof J. Rudziński, Dorota Staszek, Monika Asztemborska, Lidia Sukovata, Jerzy Raczko, Marek Cieślak, Andrzej Kolk and Rafał Szmigielski

Insects 2022, 13(11), 1063; https://doi.org/10.3390/insects13111063 - 17 Nov 2022

Cited by 1 | Viewed by 2330

Abstract

The pine-tree lappet moth, D. pini, is a harmful defoliator of pine forests in Europe and Asia and a potentially invasive species in North America. The lures for trapping D. pini males based on two known components of its sex pheromone appeared weakly [...] Read more.

The pine-tree lappet moth, D. pini, is a harmful defoliator of pine forests in Europe and Asia and a potentially invasive species in North America. The lures for trapping D. pini males based on two known components of its sex pheromone appeared weakly attractive to male moths. Identification of all components of the sex pheromone might allow for the development of more effective lures. The pheromone was sampled from virgin females using SPME and analyzed using gas chromatography coupled with mass spectrometry. Four new likely components ((Z5)-dodecenal, (Z5)-dodecen-1-ol, (Z5)-decen-1-yl acetate, (Z5)-tetradecen-1-yl acetate) and two known components ((Z5,E7)-dodecadienal, (Z5,E7)-dodecadien-1-ol) were identified based on comparison against authentic standards, Kováts indices and spectra libraries. The samples also contained several sesquiterpenes. Wind tunnel and field experiments showed that some blends of synthetic pheromone components alone or enriched with Scots pine essential oil (SPEO) were attractive to D. pini males. One component—(Z5)-decen-1-yl acetate—had a repelling effect. The presented knowledge of D. pini sex pheromone provides a basis for developing optimal lures for monitoring or controlling insect populations. Full article

(This article belongs to the Special Issue Chemical Communication in Insects: New Advances in IPM Strategies)

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9 pages, 881 KiB

Open AccessArticle

Distribution of Insecticide Resistance Genetic Markers in the West Nile Virus Vector Culex pipiens from South-Eastern Romania

by Ioana Georgeta Stancu, Florian Liviu Prioteasa, Georgiana Victorița Tiron, Ani Ioana Cotar, Elena Fălcuță, Daniela Porea, Sorin Dinu, Cornelia Svetlana Ceianu and Ortansa Csutak

Insects 2022, 13(11), 1062; https://doi.org/10.3390/insects13111062 - 17 Nov 2022

Cited by 2 | Viewed by 1618

Abstract

Culex pipiens pipiens and Culex pipiens molestus mosquitoes are the vectors of West Nile virus in south-eastern Romania, an area of intense circulation and human transmission of this virus. The level of insecticide resistance for the mosquito populations in the region has not [...] Read more.

Culex pipiens pipiens and Culex pipiens molestus mosquitoes are the vectors of West Nile virus in south-eastern Romania, an area of intense circulation and human transmission of this virus. The level of insecticide resistance for the mosquito populations in the region has not been previously assessed. Culex pipiens mosquitoes collected between 2018 and 2019 in south-eastern Romania from different habitats were subjected to biotype identification by real-time PCR. Substitutions causing resistance to organophosphates and carbamates (F290V and G119S in acetylcholinesterase 1) and to pyrethroids (L1014F in voltage gated Na⁺ channel) were screened by PCR or sequencing. Substitutions F290V and G119S were detected at very low frequencies and only in heterozygous state in Culex pipiens molestus biotype specimens collected in urban areas. The molestus biotype population analysed was entirely homozygous for L1014F, and high frequencies of this substitution were also found for pipiens biotype and hybrid mosquitoes collected in urban and in intensive agriculture areas. Reducing the selective pressure by limiting the use of pyrethroid insecticides only for regions where it is absolutely necessary and monitoring L1014F mutation should be taken into consideration when implementing vector control strategies. Full article

(This article belongs to the Section Medical and Livestock Entomology)

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12 pages, 1073 KiB

Open AccessArticle

Laboratory Evaluation and Field Feasibility of Micro-Encapsulated Insecticide Effect on Rhodnius prolixus and Triatoma dimidiata Mortality in Rural Households in Boyacá, Colombia

by Lídia Gual-Gonzalez, Manuel Medina, César Valverde-Castro, Virgilio Beltrán, Rodrigo Caro, Omar Triana-Chávez, Melissa S. Nolan and Omar Cantillo-Barraza

Insects 2022, 13(11), 1061; https://doi.org/10.3390/insects13111061 - 17 Nov 2022

Cited by 2 | Viewed by 1770

Abstract

Chagas disease is a neglected vector-borne zoonosis caused by the parasite Trypanosoma cruzi that is primarily transmitted by insects of the subfamily Triatominae. Although control efforts targeting domestic infestations of Rhodnius prolixus have been largely successful, with several regions in Boyacá department certified [...] Read more.

Chagas disease is a neglected vector-borne zoonosis caused by the parasite Trypanosoma cruzi that is primarily transmitted by insects of the subfamily Triatominae. Although control efforts targeting domestic infestations of Rhodnius prolixus have been largely successful, with several regions in Boyacá department certified free of T. cruzi transmission by intradomicile R. prolixus, novel native species are emerging, increasing the risk of disease. Triatoma dimidiata is the second most important species in Colombia, and conventional control methods seem to be less effective. In this study we evaluated the efficacy and usefulness of micro-encapsulated insecticide paints in laboratory conditions and its applicability in rural communities to avoid triatomine domiciliation. Laboratory conditions measured mortality at 6 months and 12 months, with an average mortality between 93–100% for T. dimidiata and 100% for R. prolixus. Evaluation of triatomine infestation in rural households was measured after one year, with an overall perception of effectiveness in reducing household domiciliation. Although triatomines were still spotted inside and around the homes, our findings demonstrate the ability of micro-encapsulated insecticide to prevent colonization inside the households when comparing infestation rates from previous years. Current control measures suggest insecticide spraying every six months, which implies great economic cost and logistical effort. Complementary triatomine control measures with insecticide spraying and micro-encapsulated insecticide paint would make public health efforts more efficient and reduce the frequency of treatment. Full article

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

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13 pages, 2376 KiB

Open AccessArticle

Characterizing Repellencies of Methyl Benzoate and Its Analogs against the Common Bed Bug, Cimex lectularius

by Jaime Strickland, Nicholas R. Larson, Mark Feldlaufer and Aijun Zhang

Insects 2022, 13(11), 1060; https://doi.org/10.3390/insects13111060 - 17 Nov 2022

Cited by 1 | Viewed by 2138

Abstract

Bed bug infestations are on the rise globally, and remediation efforts are becoming more expensive and difficult to achieve due to rising insecticide resistance in the pest populations. This study evaluates Cimex lectularius behavior in the presence of attractive elements—aggregation pheromone or food [...] Read more.

Bed bug infestations are on the rise globally, and remediation efforts are becoming more expensive and difficult to achieve due to rising insecticide resistance in the pest populations. This study evaluates Cimex lectularius behavior in the presence of attractive elements—aggregation pheromone or food source (human blood)—and the reported botanical repellent methyl benzoate (MB), several MB analogs, as well as the well-known insect repellent, N,N-diethyl-meta-toluamide (DEET). Utilizing EthoVision, a video tracking system, we now report that MB and several of its analogs exhibit strong spatial repellency against C. lectularius, with methyl 2-methoxybenzoate (M2MOB) and methyl 3-methoxybenzoate (M3MOB) exhibiting the strongest repellent effects. Further, our data showed that MB, M2MOB, M3MOB, and DEET exhibit repellency against a pyrethroid resistant strain of C. lectularius. Full article

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

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12 pages, 1294 KiB

Open AccessArticle

Some Considerations about Winter Colony Losses in Italy According to the Coloss Questionnaire

by Franco Mutinelli, Anna Pinto, Luciana Barzon and Marica Toson

Insects 2022, 13(11), 1059; https://doi.org/10.3390/insects13111059 - 16 Nov 2022

Cited by 6 | Viewed by 1786

Abstract

The Italian beekeeping industry has grown steadily during the last decade, according to data from the national beekeeping registry, which came into existence in February 2015. Winter colony losses remain a matter of concern for beekeepers in Italy, and administration of the questionnaire [...] Read more.

The Italian beekeeping industry has grown steadily during the last decade, according to data from the national beekeeping registry, which came into existence in February 2015. Winter colony losses remain a matter of concern for beekeepers in Italy, and administration of the questionnaire defined by the Coloss Association could contribute to a better understanding of this phenomenon. To evaluate the percentage trends over time in honeybee colony losses arising from various causes, we used the quasi-binomial generalized linear modelling (GzLM) approach, taking the year as an independent variable. We set our level of significance at 5% and performed the data analysis only for the seven regions that sent data continuously from 2014 to 2020. We considered the percentage of losses due to queen-related problems, natural disasters, and dead or empty colonies, given that these questions remained unchanged over the years. The survey also revealed that the percentage trend for respondents using drone brood removal showed a significant increase. In general, the percentage of colony losses due to queen-related problems remained lower than 8%, and the percentage of colony losses associated with natural disasters was very low (<2%). The mean percentages of losses due to dead or empty colonies ranged from 6 to 17% in the considered period. In addition, we took account of the responses relating to treatments against Varroa mite infestation, given the importance attributed to this honeybee parasite. Unlike the other variables, we calculated the percentages related to the types of beekeeper treatments against Varroa destructor based on the respondents, not on the colonies. What emerged was that almost every beekeeper used at least one type of treatment against V. destructor. In general, the trend of respondents appeared stable at 0.3% during the last four years. Full article

(This article belongs to the Special Issue Losses of Honey Bee Colonies across the World)

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14 pages, 6428 KiB

Open AccessArticle

Nesting Biology and Ecology of a Resin Bee, Megachile cephalotes (Megachilidae: Hymenoptera)

by Waseem Akram, Asif Sajjad, Hamed A. Ghramh, Mudssar Ali and Khalid Ali Khan

Insects 2022, 13(11), 1058; https://doi.org/10.3390/insects13111058 - 16 Nov 2022

Cited by 2 | Viewed by 2461

Abstract

We report the nesting biology and ecology of Megachile cephalotes Smith, 1853 for the first time in Pakistan. Wooden and bamboo trap nests were deployed at three different locations in Bahawalpur district, Pakistan, from January 2020 to May 2021. A total of 242 [...] Read more.

We report the nesting biology and ecology of Megachile cephalotes Smith, 1853 for the first time in Pakistan. Wooden and bamboo trap nests were deployed at three different locations in Bahawalpur district, Pakistan, from January 2020 to May 2021. A total of 242 nests of M. cephalotes were occupied in all three locations with the maximum abundance in the Cholistan Institute of Desert Studies. Megachile cephalotes remained active from March to September (the spring and summer seasons). In a nest, females made 7–8 brood cells each having a length of 1.2–2.3 cm. Plant resin was used to construct cells and mud or animal dung to plug the nest entrance. A vestibular cell was also made between the outermost brood cell and the nest entrance that ranged from 1.4 to 2.5 cm in length. No intercalary cells were observed in the nests. The males took 65.3 days to become adults, while the females took 74.78 days. The sex ratio was significantly biased toward females in all three locations. Grewia asiatica was the predominant pollen grain species found in the brood cells. Megachile cephalotes were observed collecting resin from Acacia nilotica, Prosopis juliflora, and Moringa oleifera. Three cleptoparasites of this species were also recorded: Euaspis carbonaria, Coelioxys sp., and Anthrax sp. This study set up a background to encourage new studies on artificial nesting and provides tools for proper biodiversity management and conservation. Full article

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

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11 pages, 1629 KiB

Open AccessArticle

Investigation of the Sandfly Fauna of Central Arid Areas and Northern Humid Regions of Tunisia, with Morphological and Molecular Identification of the Recently Established Population of Phlebotomus (Larroussius) perfiliewi

by Ifhem Chelbi, Amani Abdi, Jérôme Depaquit, Wasfi Fares, Mohammed Abdo Saghir Abbas, Khalil Dachraoui and Elyes Zhioua

Insects 2022, 13(11), 1057; https://doi.org/10.3390/insects13111057 - 16 Nov 2022

Viewed by 1812

Abstract

Based on nucleotide sequences, we re-identified representative samples of Phlebotomus perfiliewi originating from two different biogeographical areas of Tunisia, whose populations had previously been identified based on morphological criteria. A partial region of the mitochondrial DNA cytochrome b gene was targeted, and sandfly [...] Read more.

Based on nucleotide sequences, we re-identified representative samples of Phlebotomus perfiliewi originating from two different biogeographical areas of Tunisia, whose populations had previously been identified based on morphological criteria. A partial region of the mitochondrial DNA cytochrome b gene was targeted, and sandfly species was determined by analogy with DNA sequences available in the GenBank database via a BLAST analysis, taking into account the query coverage and percentage identity. The recognized species presents the most substantial homology with the analyzed sequence. The results of the molecular identification showed complete agreement with the morphological identifications, and Phlebotomus perfiliewi is genetically variable. Full article

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

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11 pages, 1539 KiB

Open AccessArticle

Identification and Field Evaluation of Sex Pheromone Components and Its Antagonist Produced by a Major Tea Pest, Archips strojny (Lepidoptera: Tortricidae)

by Nanxia Fu, Fida Hussain Magsi, Yingjie Zhao, Xiaoming Cai, Zhaoqun Li, Lei Bian, Chunli Xiu, Zongmao Chen and Zongxiu Luo

Insects 2022, 13(11), 1056; https://doi.org/10.3390/insects13111056 - 15 Nov 2022

Cited by 4 | Viewed by 2877

Abstract

Pesticide application is the only known control method for the tea tortrix Archips strojny (Lepidoptera: Tortricidae), which is a major pest of spring tea in China. To develop sex pheromone-based, environmentally safe control strategies, here we identified the sex pheromone components of this [...] Read more.

Pesticide application is the only known control method for the tea tortrix Archips strojny (Lepidoptera: Tortricidae), which is a major pest of spring tea in China. To develop sex pheromone-based, environmentally safe control strategies, here we identified the sex pheromone components of this species. The male moths’ antennae responded electrophysiologically to two compounds in female pheromone gland extracts. Gas chromatography–mass spectrometry analysis indicated that the two bioactive compounds were (Z)-11-tetradecenyl acetate (Z11-14:Ac) and (Z)-11-tetradecenyl alcohol (Z11-14:OH). Field trapping assays showed that lures baited with only the major component Z11-14:Ac were the most attractive to male moths, and the attractiveness decreased significantly when the lure was impregnated with increased relative ratios of the minor component Z11-14:OH. Our study demonstrated that Z11-14:Ac was the major attractant in the A. strojny sex pheromone, and the minor component Z11-14:OH seemed to serve as an antagonist. The results indicate that lures baited with 1 mg of Z11-14:Ac could be used as a monitoring or mass trapping tool for A. strojny management in Chinese tea plantations. Furthermore, Z11-14:Ac was identified as a common sex pheromone attractant of nine Archips species; these results lay the foundation for developing mating disruption techniques that target multiple leafroller pests. Full article

(This article belongs to the Special Issue From Insect Pheromones to Mating Disruption: Theory and Practice (Volume II))

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12 pages, 1517 KiB

Open AccessArticle

Kairomonal Effect of Aphid Alarm Pheromones and Analogs on the Parasitoid Diaeretiella rapae

by Yaoguo Qin, Shangyang Zhang and Zhengxi Li

Insects 2022, 13(11), 1055; https://doi.org/10.3390/insects13111055 - 15 Nov 2022

Cited by 1 | Viewed by 1843

Abstract

Aphid alarm pheromones, as important semiochemicals, not only mediate behavioral response of aphids, but can also act as kairomones to attract their natural enemies. The sesquiterpene (E)-β-farnesene (EβF), the major alarm pheromone component of most aphid species, has been shown to have a [...] Read more.

Aphid alarm pheromones, as important semiochemicals, not only mediate behavioral response of aphids, but can also act as kairomones to attract their natural enemies. The sesquiterpene (E)-β-farnesene (EβF), the major alarm pheromone component of most aphid species, has been shown to have a kairomonal effect on the predators of aphids, but other alarm pheromone components, especially the monoterpenes and analogs, are rarely investigated. Here, two EβF analogs were successfully synthesized via the nucleophilic substitution reaction, and we then examined the kairomonal effects of four alarm pheromone components and two EβF analogs on the aphid parasitoid, Diaeretiella rapae. In olfactory bioassays, D. rapae females generally showed no significant behavioral response to these alarm pheromone components and analogs under low concentrations (0.1 μg/μL). Nevertheless, their olfactory response to these compounds gradually enhanced with increasing concentrations. Among the four pheromone components, EβF showed the highest attractive activity, but the parasitoid preferred blends over single compounds. Moreover, the response time decreased as the concentration increased. We confirmed the kairomonal effect of monoterpene alarm pheromone components and their blends, in addition to EβF, on the natural enemies of aphids. This is the first report that the blend of alarm pheromone components and their analogs has a stronger kairomonal effect than do the single components on the natural enemies of aphids. This study contributes to our understanding of the mechanisms involved in the regulation of parasitoid behaviors by kairomones and provides a promising opportunity for designing kairomones for the aphid parasitoid to mediate aphid populations in the field. Full article

(This article belongs to the Topic Pheromone Production and Perception: From Genetics to Behaviors)

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13 pages, 2662 KiB

Open AccessArticle

The Effect of Environmental Factors on the Diversity of Crane Flies (Tipulidae) in Mountainous and Non-Mountainous Regions of the Qinghai-Tibet Plateau and Surrounding Areas

by Qicheng Yang, Wei Chen, Lishan Qian, Ding Yang, Xiaoyan Liu and Manqun Wang

Insects 2022, 13(11), 1054; https://doi.org/10.3390/insects13111054 - 15 Nov 2022

Cited by 2 | Viewed by 1811

Abstract

Tipulidae, one of the most diverse families of Diptera, is widely distributed in the world. The adults have weak flight ability, making it an ideal model for studying the formation of insect diversity. This study aims to explore the species diversity and endemism [...] Read more.

Tipulidae, one of the most diverse families of Diptera, is widely distributed in the world. The adults have weak flight ability, making it an ideal model for studying the formation of insect diversity. This study aims to explore the species diversity and endemism of Tipulidae in the Qinghai-Tibet Plateau and the surrounding areas, as well as analyze the relationships between the diversity pattern and 25 environmental factors in mountainous and non-mountainous regions. To this end, we collected 2589 datasets for the distribution of 1219 Tipulidae species, and found three areas with high diversities of Tipulidae around the QTP, including the Sikkim-Yadong area, Kamen River Basin, and Gongga Mountain. Further R, generalized additive model (GAM), and stepwise multiple regression analysis indicated that the richness and endemism of Tipulidae is mainly influenced by the warmest quarter precipitation and topographic heterogeneity in mountainous regions, but in non-mountainous regions, the richness is mostly affected by the precipitation seasonality, while there is no regularity in the relationship between endemism and environmental factors. In addition, the richness model in mountainous regions was in conformity with the results of GAM. Full article

(This article belongs to the Special Issue Climate Sensitive Ecological and Dynamical Models of Insects)

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13 pages, 1158 KiB

Open AccessArticle

Genetic Relationships and Signatures of Adaptation to the Climatic Conditions in Populations of Apis cerana Based on the Polymorphism of the Gene Vitellogenin

by Rustem A. Ilyasov, Slađan Rašić, Junichi Takahashi, Valery N. Danilenko, Maxim Y. Proshchalykin, Arkady S. Lelej, Vener N. Sattarov, Pham Hong Thai, Rika Raffiudin and Hyung Wook Kwon

Insects 2022, 13(11), 1053; https://doi.org/10.3390/insects13111053 - 15 Nov 2022

Cited by 1 | Viewed by 1912

Abstract

Apis cerana and Apis mellifera are important honey bee species in Asia. A. cerana populations are distributed from a cold, sharply continental climate in the north to a hot, subtropical climate in the south. Due to the Sacbrood virus, almost all A. cerana [...] Read more.

Apis cerana and Apis mellifera are important honey bee species in Asia. A. cerana populations are distributed from a cold, sharply continental climate in the north to a hot, subtropical climate in the south. Due to the Sacbrood virus, almost all A. cerana populations in Asia have declined significantly in recent decades and have recovered over the past five years. This could lead to a shift in the gene pool of local A. cerana populations that could affect their sustainability and adaptation. It was assumed that adaptation of honey bees could be observed by comparative analysis of the sequences of genes involved in development, labor division, and caste differentiation, such as the gene Vitellogenin VG. The VG gene nucleotide sequences were used to assess the genetic structure and signatures of adaptation of local populations of A. cerana from Korea, Russia, Japan, Nepal, and China. A. mellifera samples from India and Poland were used as the outgroup. The signatures of adaptive selection were found in the local population of A. cerana using VG gene sequence analysis based on Jukes–Cantor genetic distances, cluster analysis, dN/dS ratio evaluation, and Tajima’s D neutrality test. Based on analysis of the VG gene sequences, Apis cerana koreana subspecies in the Korean Peninsula were subdivided into three groups in accordance with their geographic localization from north to south. The VG gene sequences are acceptable tools to study the sustainability and adaptation of A. cerana populations. Full article

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

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17 pages, 5038 KiB

Open AccessArticle

Prediction of the Current and Future Distributions of the Hessian Fly, Mayetiola destructor (Say), under Climatic Change in China

by Qi Ma, Jin-Long Guo, Yue Guo, Zhi Guo, Ping Lu, Xiang-Shun Hu, Hao Zhang and Tong-Xian Liu

Insects 2022, 13(11), 1052; https://doi.org/10.3390/insects13111052 - 15 Nov 2022

Cited by 3 | Viewed by 2460

Abstract

The Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), is a destructive wheat pest worldwide and an important alien species in China. Based on 258 distribution records and nine environmental factors of the Hessian fly, we predicted the potential distribution area in China under [...] Read more.

The Hessian fly, Mayetiola destructor (Say) (Diptera: Cecidomyiidae), is a destructive wheat pest worldwide and an important alien species in China. Based on 258 distribution records and nine environmental factors of the Hessian fly, we predicted the potential distribution area in China under three current and future (2050s and 2070s) climate change scenarios (RCP2.6, RCP4.5, and RCP8.5) via the optimized MaxEnt model. Under the current climate conditions, the suitable distribution areas of the Hessian fly in China were 25–48° N, 81–123° E, and the total highly suitable distribution area is approximately 9.63 × 10⁵ km², accounting for 9.99% of the total national area. The highly suitable areas are mainly located in northern Xinjiang and central and eastern China. With the rising global temperatures, except for the high-suitable areas under the RCP8.5 scenario, most potential geographic distribution areas would expand in the future. The minimum temperature in February (tmin-2), precipitation in March (prec-3), maximum temperature in November (tmax-11), and precipitation seasonality (bio-15) are important factors that affect the potential geographic distribution of the Hessian fly. This study provides an important reference and empirical basis for management of the Hessian fly in the future. Full article

(This article belongs to the Special Issue Invasive Pest Management and Climate Change)

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7 pages, 859 KiB

Open AccessCommunication

A Chemical Lure for Trapping Both Sexes of Amata phegea L.

by Szabolcs Szanyi, Antal Nagy, István Szarukán, Zoltán Varga, Júlia Katalin Jósvai and Miklós Tóth

Insects 2022, 13(11), 1051; https://doi.org/10.3390/insects13111051 - 15 Nov 2022

Cited by 1 | Viewed by 1838

Abstract

The addition of synthetic eugenol and benzyl acetate to the known floral chemical and moth attractant phenylacetaldehyde synergized the attraction of Amata phegea (Lepidoptera: Amatidae). Traps baited with the ternary blend caught ca. four times more A. phegea moths than traps baited [...] Read more.

The addition of synthetic eugenol and benzyl acetate to the known floral chemical and moth attractant phenylacetaldehyde synergized the attraction of Amata phegea (Lepidoptera: Amatidae). Traps baited with the ternary blend caught ca. four times more A. phegea moths than traps baited with phenylacetaldehyde alone. Both female and male moths were attracted; in a preliminary test, the female numbers caught were almost double compared to the males. Most A. phegea were caught when the blend was formulated in a dispenser with medium release rates. Traps baited with the ternary lure in polyethylene bag dispensers detected a single well-pronounced peak in seasonal trapping, suggesting that this multicomponent bisexual lure could be efficient enough to be applied to the detection and monitoring of female and male A. phegea. Full article

(This article belongs to the Special Issue Invertebrate Conservation: Challenges and Ways Forward)

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18 pages, 2517 KiB

Open AccessArticle

The MosHouse^® Trap: Evaluation of the Efficiency in Trapping Sterile Aedes aegypti Males in Semi-Field Conditions

by Pattamaporn Kittayapong, Rungrith Kittayapong, Suwannapa Ninphanomchai and Wanitch Limohpasmanee

Insects 2022, 13(11), 1050; https://doi.org/10.3390/insects13111050 - 14 Nov 2022

Cited by 2 | Viewed by 2143

Abstract

Arbovirus diseases, such as dengue, chikungunya, and Zika, are important public health problems. Controlling the major vector, Aedes aegypti, is the only approach to suppressing these diseases. The surveillance of this mosquito species needs effective collecting methods. In this study, a simple [...] Read more.

Arbovirus diseases, such as dengue, chikungunya, and Zika, are important public health problems. Controlling the major vector, Aedes aegypti, is the only approach to suppressing these diseases. The surveillance of this mosquito species needs effective collecting methods. In this study, a simple MosHouse sticky trap was evaluated in a semi-field condition. Our results demonstrated the efficiency of this trap in collecting Ae. aegypti males, and no significant difference (p > 0.05) in the numbers of males was detected when compared with the widely used BG- Sentinel trap. However, there were significantly lower numbers of females (p < 0.05) collected using the MosHouse trap when compared to the BG-Sentinel trap. We also found a significant difference (p < 0.05) in the collected numbers between irradiated and non-irradiated males. More irradiated males were collected in the MosHouse traps. The improvement of male collection was achieved with the addition of a sugar stick and sticky flags. Significantly higher numbers of males were collected in the MosHouse trap with sticky flags compared to the original one when they were released independently of females, but both were collected in higher numbers when they were released together (p < 0.05). In conclusion, our experiments demonstrated that the MosHouse trap could sample Ae. aegypti, especially males, as efficiently as the established BG-Sentinel trap, while the cost was more than 50 times lower, showing the potential of the MosHouse trap for improved Ae. aegypti male and female surveillance with very large numbers of traps at affordable costs. In addition, significantly (p < 0.001) increased male sampling was achieved by adding an external sticky flag on the MosHouse trap, providing an avenue for further development of the novel male-trapping strategy. Full article

(This article belongs to the Special Issue Mosquito Handling, Transport, Release and Male Trapping Methods)

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6 pages, 2107 KiB

Open AccessBrief Report

Novel Observation: Northern Cardinal (Cardinalis cardinalis) Perches on an Invasive Jorō Spider (Trichonephila clavata) Web and Steals Food

by Arty Schronce and Andrew K. Davis

Insects 2022, 13(11), 1049; https://doi.org/10.3390/insects13111049 - 13 Nov 2022

Cited by 3 | Viewed by 3261

Abstract

An invasive spider (Trichonephila clavata [L. Koch 1878], or jorō spider) is rapidly expanding throughout the southeast of the United States, engendering many questions about how native fauna will be affected. Here, we describe an observation of a northern cardinal (Cardinalis [...] Read more.

An invasive spider (Trichonephila clavata [L. Koch 1878], or jorō spider) is rapidly expanding throughout the southeast of the United States, engendering many questions about how native fauna will be affected. Here, we describe an observation of a northern cardinal (Cardinalis cardinalis, L.) consuming prey items from a jorō web, which serves as an example of a native species deriving a (small) benefit from this new invader. Moreover, the manner of the kleptoparasitism is also noteworthy; the cardinal perched directly on the web, which supported its weight (which is 42–48 g in this species). This appears to be the first documented case of a spider web supporting a perching bird. We also include measurements of other jorō webs, where web strength had been assessed using a force gauge, which revealed that typical webs can support masses up to 70 g before collapsing. Collectively, this information adds to the small but growing body of knowledge about the biology of this non-native spider. Full article

(This article belongs to the Special Issue Spider Ecology and Behaviour)

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19 pages, 7500 KiB

Open AccessArticle

Analysis of the Genetic Variation of the Fruitless Gene within the Anopheles gambiae (Diptera: Culicidae) Complex Populations in Africa

by Mahamadi Kientega, Nace Kranjc, Nouhoun Traoré, Honorine Kaboré, Dieudonné Diloma Soma, Ioanna Morianou, Moussa Namountougou, Adrien Marie Gaston Belem and Abdoulaye Diabaté

Insects 2022, 13(11), 1048; https://doi.org/10.3390/insects13111048 - 13 Nov 2022

Cited by 2 | Viewed by 2333

Abstract

Targeting genes involved in sexual determinism, for vector or pest control purposes, requires a better understanding of their polymorphism in natural populations in order to ensure a rapid spread of the construct. By using genomic data from An. gambiae s.l., we analyzed the [...] Read more.

Targeting genes involved in sexual determinism, for vector or pest control purposes, requires a better understanding of their polymorphism in natural populations in order to ensure a rapid spread of the construct. By using genomic data from An. gambiae s.l., we analyzed the genetic variation and the conservation score of the fru gene in 18 natural populations across Africa. A total of 34,339 SNPs were identified, including 3.11% non-synonymous segregating sites. Overall, the nucleotide diversity was low, and the Tajima’s D neutrality test was negative, indicating an excess of low frequency SNPs in the fru gene. The allelic frequencies of the non-synonymous SNPs were low (freq < 0.26), except for two SNPs identified at high frequencies (freq > 0.8) in the zinc-finger A and B protein domains. The conservation score was variable throughout the fru gene, with maximum values in the exonic regions compared to the intronic regions. These results showed a low genetic variation overall in the exonic regions, especially the male sex-specific exon and the BTB-exon 1 of the fru gene. These findings will facilitate the development of an effective gene drive construct targeting the fru gene that can rapidly spread without encountering resistance in wild populations. Full article

(This article belongs to the Special Issue Biology, Genetics and Evolution of Mosquitoes)

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12 pages, 974 KiB

Open AccessArticle

Evaluation of Insecticidal Potentials of Five Plant Extracts against the Stored Grain Pest, Callosobruchus maculatus (Coleoptera: Bruchidae)

by Rasheed Akbar, Imtiaz Ali Khan, Reem A. Alajmi, Ashraf Ali, Brekhna Faheem, Amjad Usman, Ashraf M. Ahmed, Mohamed El-Shazly, Abid Farid, John P. Giesy and Mourad A. M. Aboul-Soud

Insects 2022, 13(11), 1047; https://doi.org/10.3390/insects13111047 - 13 Nov 2022

Cited by 13 | Viewed by 4733

Abstract

Plant based insecticides are considered among the most economic and ecofriendly chemicals for the protection of plants and stored grains. The cowpea weevil (Callosbruchus maculatus) causes more than 90% damage to sored grains in three to six months. The current study [...] Read more.

Plant based insecticides are considered among the most economic and ecofriendly chemicals for the protection of plants and stored grains. The cowpea weevil (Callosbruchus maculatus) causes more than 90% damage to sored grains in three to six months. The current study investigates insecticidal potentials of five selected botanicals: Melia azedarach, Nicotiana rustica, Azadirachta indica, Nicotiana tabacum and Thuja orientalis. They are explored at six different concentrations (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0%) against C. maculatus and compared to effects of distilled water which is used as a control. Toxicities of 3%(V/V) extracts of N. tabacum, N. rustica, A. indica and T. orientalis against C. maculatus were 100%, 86.11%, 80.56% and 72.22%, respectively. Maximum mortality was caused by N. tabacum and N. rustica (100%), followed by A. indica (82%), whereas minimum mortality was observed in T. orientalis (64%) at 2.5%. Several phytochemicals, alkaloids, saponins, diterphenes, phytosterol, flavonoids and phenols were identified in N. tabacum and N. rustica, while few were present in A. indica. Phytosterol was present in greatest abundance. Saponins were only detected in aqueous extracts of N. rustica and N. tabacum. Taken together, these results indicate the utility of N. tabacum, N. rustica and A. indica as potential botanicals to control pest beetle and cowpea weevil. Full article

(This article belongs to the Special Issue Botanical Control of Insect Pests)

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17 pages, 1557 KiB

Open AccessArticle

Reference Genes for Expression Analysis Using RT-qPCR in Cnaphalocrocis medinalis (Lepidoptera: Pyralidae)

by Xiaoyu Zhao, Jiawen Guo, Yanhui Lu, Tianyi Sun, Junce Tian, Jianlei Huang, Hongxing Xu, Zhengliang Wang and Zhongxian Lu

Insects 2022, 13(11), 1046; https://doi.org/10.3390/insects13111046 - 13 Nov 2022

Cited by 9 | Viewed by 2335

Abstract

Cnaphalocrocis medinalis is a destructive migratory rice pest. Although many studies have investigated its behavioral and physiological responses to environmental changes and migration-inducing factors, little is known about its molecular mechanisms. This study was conducted to select suitable RT-qPCR reference genes to facilitate [...] Read more.

Cnaphalocrocis medinalis is a destructive migratory rice pest. Although many studies have investigated its behavioral and physiological responses to environmental changes and migration-inducing factors, little is known about its molecular mechanisms. This study was conducted to select suitable RT-qPCR reference genes to facilitate future gene expression studies. Here, thirteen candidate housekeeping genes (EF1α, AK, EF1β, GAPDH, PGK, RPL13, RPL18, RPS3, 18S rRNA, TBP1, TBP2, ACT, and UCCR) were selected to evaluate their stabilities under different conditions using the ∆CT method; the geNorm, NormFinder, BestKeeper algorithms; and the online tool RefFinder. The results showed that the most stable reference genes were EF1β, PGK, and RPL18, related to developmental stages; RPS3 and RPL18 in larval tissues; EF1β and PGK in larvae feeding on different rice varieties; EF1α, EF1β, and PGK in larvae temperature treatments; PGK and RPL13, related to different adult ages; PGK, EF1α, and ACT, related to adult nutritional conditions; RPL18 and PGK, related to adult mating status; and, RPS3 and PGK, related to different adult take-off characteristics. Our results reveal reference genes that apply to various experimental conditions and will greatly improve the reliability of RT-qPCR analysis for the further study of gene function in this pest. Full article

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

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Insects, Volume 13, Issue 11 (November 2022) – 109 articles

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