Entomological Research最新文献

Micronutrient deficiency is emerging as a significant public health concern in India. Facilitating pollinator populations in agroecosystems could be an efficient mechanism to ensure food production, both quantitatively and qualitatively. To better understand the role of pollinators in the agroecosystems of India, we conducted an analysis of crop production based on their reliance on pollinators during the period 2010–2021. Our findings indicate that although there were no significant changes in the yearly production or cultivation area of various pollinator-dependent crops, the average yearly rate of crop-yield increase in pollinator-dependent crops was notably lower than in crops that did not depend on pollinators during 2015–2021. The study highlights that a significant portion of vitamins, particularly B7, B9, C and K, and carotenoids come from pollinator-dependent crops. The findings of this study, which highlight the considerable contribution of micronutrients originating from pollinator-dependent crops, are consistent with results observed in the Republic of Korea. The loss of pollinator populations may result in an approximately 19% deficit in vitamin C. Although vegetables and fruits contain substantial quantities of minerals per unit weight, a significant portion of these minerals is sourced from non-pollinator-dependent crops, particularly cereals and pulses, owing to their abundance. We propose that pollinator-friendly habitat management could be a sustainable solution to avoid the negative consequences associated with reduced food and nutrition arising from a lack of pollinators in agroecosystems.

Ticks are vectors of disease-causing pathogens and are found on domestic and wild animals; thus, they are also vectors of significant human diseases. For this reason, pre-emptive measures to prevent tick-borne diseases are necessary in the form of exploring their major habitats, population increase period, and factors affecting their population growth, all of which indicate the purpose of this study. In the study, a variation of Haemaphysalis longicornis, a major vector of fever-causing conditions, was statistically analyzed to identify the spatial and climatic factors affecting the time-dependent variations of its population. The survey occurred in different habitats (grassland, mixed forest, deciduous forest, and coniferous forest) in South Korea. In addition, we fitted a phenology model by using a probability function to find the peak occurrence time annually. As a result, the numbers of adults and nymphs were found to be related to temperature and relative humidity and their population peaked at the end of May in all habitats except deciduous forests. This study is expected to provide information on habitat types, times, and climate patterns that require attention to help control H. longicornis populations.

This study focused on a kleptoparasitic bee, Melecta chinensis, which is not well-known in the Republic of Korea. We provided a detailed morphological illustration of the adult bees and their nesting biological characteristics with distributional data. Additionally, the complete mitochondrial genome of the species is presented for the first time, and its phylogenetic position within the family Apidae is estimated.

As a result, we could suggest a full redescription of M. chinenesis for identification and a newly reported potential flower host for it. In addition, the mitochondrial DNA (mtDNA) of M. chinensis is revealed as 15,489 base pairs (bp) long, with 35 eukaryotic mitochondrial genes (13PCGs, 2 rRNAs, and 20 tRNAs) and a 706 bp AT-rich region. The overall base composition is 75.82% AT and 24.18% GC. The 13 protein-coding genes (PCGs) started with a typical ATN codon (ATA in nine genes and ATG in four genes) and terminated with TNN (TAN in 10 genes and TTT in one gene) or ANN (AAC in one gene and ATT in one gene). The phylogenetic results based on 13 PCGs showed that M. chinensis is distantly positioned to bumble bees (Bombus) and honey bees (Apis) but closely related to a stingless bee, Frieseomelitta varia, within the family.

Cockroaches are insects found in almost all habitats, including unsanitary environments. Understanding their microbial communities is crucial for assessing the potential risks they pose as vectors of pathogens. In this study, we assessed the microbial communities of omnivorous cockroaches collected from external environments and those reared in a clean laboratory for extended periods (5–20 years). Using the iSeq 100 system, we examined the relative abundance of microbial communities at the phylum, family and genus levels. Our results revealed that the predominant taxa in these cockroaches were Proteobacteria, Bacteroidetes and Firmicutes. Interestingly, the bacterial communities of samples from the same cockroach species, regardless of their living conditions, clustered together, indicating species-specific similarities in microbiomes. The symbiont genus Blattabacterium was consistently present in all samples, delivering nutrients to the host. Pathogen detection at the genus level indicated a higher prevalence of potential pathogens in cockroaches collected from field environments, compared with those from laboratory-reared cockroaches. These findings underscore the importance of cockroaches as pathogen reservoirs and vectors of opportunistic infections, emphasizing the need for further studies to identify specific microorganisms and confirm their pathogenicity. As cockroaches inhabit human environments, their potential to spread harmful bacteria through defecation warrants attention and underscores the significance of understanding their microbial ecology for public health implications.

As most drosophilid species are not considered as primary pest, studies of their communities in natura, with standardized surveys, are relatively sparse. However, Drosophila suzukii and its rapid expansion through the world led to the implementation of many monitoring programs. As part of a research project on D. suzukii, we set up in 2022 an annual fly monitoring in 16 fruits plantations in France to understand population's dynamics of D. suzukii and to broadly survey drosophilid communities. The captures led to the first observation of Zaprionus tuberculatus in mainland France. Over the whole monitoring, we trapped a total of 111 specimens in a fig orchard located in southern France (Salses-le-Château), both in fig trees and nearby hedgerow. The first detection of Zaprionus tuberculatus occurred in July 2022 in the hedgerow, and captures continued until January 2023 with an interruption in November and December. In addition, in this orchard we collected overripe figs in September 2023 from which over 20 Z. tuberculatus have emerged in the following 2 weeks, confirming the establishment of a permanent population. The pest status of Z. tuberculatus and its potential risk for agriculture is not yet clear, but the pest behavior of the close-relative species Zaprionus indianus, especially on figs, should be a warning point for the entry of Z. tuberculatus into the EU and France, as they may have similar polyphagous habit. The pest status and range expansion of Z. tuberculatus should be assessed to estimate risk to fruit's production.

Silk fibroin from Bombyx mori has traditionally been utilized for garment production; however, recently, it has become feasible to manufacture edible and cosmetic products using this material. Gamma-ray irradiation can improve physiological activity through the modification of the structure of proteins in biological materials. In this study, we examined whether gamma ray-irradiated fibroin protein (gFP) has a protective effect on tumor necrosis factor alpha (TNF-α)-induced cellular stress through a change in protein structure. First, we confirmed that the structure of FP was changed by gamma-ray irradiation using electrophoresis, UV spectra and Fourier-transform infrared spectroscopy (FT-IR). We further investigated the cytoprotective potential of 20 kGy-irradiated fibroin protein (gFP20) in human skin keratinocytes (HaCaT cells) exposed to extracellular stress. gFP20 effectively decreased TNF-α-induced matrix metalloproteinase-1 (MMP-1) overexpression and restored reduced type-1 procollagen in HaCaT cells. This reduction occurred concomitantly with suppressed nuclear factor-κB (NF-κB) nuclear translocation, resulting in a decreased level of inflammatory mediator and pro-inflammatory cytokines. Furthermore, gFP20 protected cells from TNF-α-induced oxidative stress by attenuating reactive oxygen species (ROS) overexpression and increasing the production of the antioxidant enzyme heme oxygenase-1 (HO-1) through the stimulation of the translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) into the nucleus. Taken together, our findings indicate that low-dose irradiated fibroin protein (gFP20) could be considered as a functional material for skincare products.

Selective herbicides are used to control undesirable vegetation or weeds in fields without harming crops. Herbicide use for weed management can directly impact the densities of insect pests in agricultural communities as a result of insect mortality during and immediately after application. In insects, the glutathione S-transferase (GST) enzyme is involved in both the detoxification process and the defense of cellular membranes against oxidative damage. In this study, two TmGSTs (TmGST-iso1 and TmGST-iso2) were identified and characterized to elucidate the GST family in Tenebrio molitor. Among the developmental stages of T. molitor, eggs had the highest expression levels of TmGST-iso1. TmGST-iso2 expression was highest in the pre-pupal stage. TmGST-iso1 expression was high in the guts of early and late larvae, whereas TmGST-iso2 expression was not observed in early larvae. Adults, both male and female, had the highest levels of TmGST-iso1 mRNA expression in the gut and reproductive organs, and the highest levels of TmGST-iso2 expression in the reproductive organs. Quantitative polymerase chain reaction was used to investigate the impact of treatment with butachlor on the mRNA expression of TmGST-iso1 and TmGST-iso2 in larvae. TmGST-iso1 expression increased in the butachlor-treated group after 3 and 24 h, whereas TmGST-iso2 expression peaked at 24 h after treatment. This study provides vital information about the detoxifying activities of T. molitor.

Wasp venom is rich in bioactive substances, such as proteins, peptides, and small molecules. The venom significantly affects the mammalian cardiovascular, nervous, and immune systems, causing mild to severe symptoms following stings. It exhibits both procoagulant and anticoagulant activities, and significant research has identified its ability to modulate the mammalian coagulation system. Active substances that inhibit clotting have been identified and purified through patient case reports and experimental studies. This study reviewed the findings on how wasp venom interacts with platelets and coagulation factors, such as fibrinogen and prothrombin, and demonstrated its dual influence on the coagulation cascade. This highlights the potential of the venom in therapeutic applications, especially as an anticoagulant, as evidenced by the inhibition of coagulation factors and prolonged clotting times after envenomation, suggesting its utility in developing novel anticoagulant therapies. This review focuses on the anticoagulant effects of social wasp venom, which is prevalent in sting incidents, summarizing the research and observations on its therapeutic potential. This emphasizes the significance of further studies to identify and utilize venom components as innovative anticoagulant treatments.

Melon thrips, Thrips palmi (Thysanoptera: Thripidae), is a serious insect pest in crop productions, and synthetic chemicals are frequently used to control them. However, this practice causes residual issue in nature and makes melon thrips acquire strong resistance. To overcome these problems, a group of entomopathogenic fungi could be used as an alternative for controlling melon thrips. In this work, a total of 100 fungal isolates from soil in four different regions of Korea were isolated and subjected to virulence assays against melon thrips. Twenty-five highly virulent fungal isolates, which showed 100% mortality 6 days after treatment, were determined. Liquid-cultured filtrates of the selected isolates were further used to investigate their insecticidal activity against melon thrips, and of the 25 selected isolates finally seven isolates including Metarhizium spp. and Fusarium spp. showed high insecticidal activity in a dose-dependent manner. Under a thermal stress at 121°C, culture filtrates of the seven isolates still kept their insecticidal activities. When liquid-cultured spores were exposed to 45°C, spores of Fusarium isolates were resistant to the thermal stress, but those of Metarhizium isolates were susceptible to the stress. The culture filtrates of Fusarium isolates did not show any phytotoxicity to the tomato plants, followed by no phytotoxicity of liquid-cultured spores, although mycotoxins need to be further clearly characterized. This work suggests that entomopathogenic Fusarium isolates are competitive in virulence against melon thrips and production of insecticidal metabolites compared to Metarhizium, and particularly attractive in sporal resistance against thermal stress, significantly stronger than Metarhizium.

Mosquitoes around the world spread diseases like malaria, dengue, zika, lymphatic filariasis and arboviruses, which are dangerous to human health and the economy. Eventually, mosquitoes develop resistance to synthetic chemical insecticides and, moreover, these insecticides have adverse environmental impacts, accumulating in soils and in the food chain. So, researchers are searching for better vector control tools from biological sources such as plants, bacteria, fungi, viruses and other predators. Eco-friendly methods that use entomopathogenic fungi to reduce vector-borne disease burdens are becoming more popular because they are selective and safe for the environment. Based on existing literature, several microbial agents show potential for the biocontrol of mosquitoes. With advances in genetic recombination and transformation techniques, in the ongoing battle against insecticide-resistant mosquitoes, genetically engineered fungal biopesticides represent a cutting-edge solution. These biopesticides are the result of novel genetic changes that improve the ability of fungi to target and kill mosquitoes. These fungi can effectively combat mosquito populations by introducing genes that produce insecticidal proteins or toxins. This method has several advantages, including a lower environmental impact, because the fungi are highly specific to mosquitoes and are harmless to non-target organisms. It also helps to reduce the problem of insecticide resistance because the fungi have a unique mode of action. These biopesticides hold great promise for reducing mosquito-borne diseases while minimizing environmental damage and combating resistance. This review article discusses various entomopathogenic fungal pathogens that can act as biocontrol agents and their mode of action against mosquitoes. We discus recent advances in entomopathogenic fungi-secreted effector molecules for suppressing host immunity and progress in the development of transgenic mosquito-killing fungi.