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BACKGROUND: Dorcus stag beetles in broad sense are one of the most diverse group in Lucanidae and important saproxylic insects playing a crucial role in nutrient recycling and forest biomonitoring. However, the dazzling morphological differentiations have caused numerous systematic confusion within the big genus, especially the puzzlingly generic taxonomy. So far, there is lack of molecular phylogenetic study to address the chaotic situation. In this study, we undertook mitochondrial genome sequencing of 42 representative species including 18 newly-sequenced ones from Eastern Asia and reconstructed the phylogenetic framework of stag beetles in Dorcus sensu lato for the first time. RESULTS: The mitogenome datasets of Dorcus species have indicated the variable mitogenomic lengths ranged from 15,785 to 19,813 bp. Each mitogenome contained 13 PCGs, 2 rRNAs, 22 tRNAs, and a control region, and all PCGs were under strong purifying selection (Ka/Ks < 1). Notably, we have identified the presence of a substantial intergenic spacer (IGS) between the trnAser (UCN) and NAD1 genes, with varying lengths ranging from 129 bp (in D. hansi) to 158 bp (in D. tityus). The mitogenomic phylogenetic analysis of 42 species showed that Eastern Asia Dorcus was monophyletic, and divided into eight clades with significant genetic distance. Four of them, Clade VIII, VII, VI and I are clustered by the representative species of Serrognathus Motschulsky, Kirchnerius Schenk, Falcicornis Séguy and Dorcus s.s. respectively, which supported their fully generic positions as the previous morphological study presented. The topology also showed the remaining clades were distinctly separated from the species of Dorcus sensu lato, which implied that each of them might demonstrate independent generic status. The Linnaeus nomenclatures were suggested as Eurydorcus Didier stat. res., Eurytrachellelus Didier stat. res., Hemisodorcus Thomson stat. res. and Velutinodorcus Maes stat. res. For Clade V, IV, III and II respectively. CONCLUSION: This study recognized the monophyly of Dorcus stag beetles and provided a framework for the molecular phylogeny of this group for the first time. The newly generated mitogenomic data serves as a valuable resource for future investigations on lucanid beetles. The generic relationship would facilitate the systematics of Dorcus stag beetles and thus be useful for exploring their evolutionary, ecological, and conservation aspects.
Assuntos
Besouros , Genoma Mitocondrial , Filogenia , Animais , Besouros/genética , Besouros/classificação , Genoma Mitocondrial/genética , Ásia OrientalRESUMO
Despite the widespread usage to safeguard crops and manage pests, pesticides have detrimental effects on the environment and human health. The necessity to find sustainable agricultural techniques and meet the growing demand for food production has spurred the quest for pesticide substitutes other than traditional ones. The unique qualities of nanotechnology, including its high surface area-to-volume ratio, controlled release, and better stability, have made it a promising choice for pest management. Over the past ten years, there has been a noticeable growth in the usage of nanomaterials for pest management; however, concerns about their possible effects on the environment and human health have also surfaced. The purpose of this review paper is to give a broad overview of the worldwide trends and environmental effects of using nanomaterials in place of pesticides. The various types of nanomaterials, their characteristics, and their possible application in crop protection are covered. The limits of the current regulatory frameworks for nanomaterials in agriculture are further highlighted in this review. Additionally, it describes how standard testing procedures must be followed to assess the effects of nanomaterials on the environment and human health before their commercialization. In order to establish sustainable and secure nanotechnology-based pest control techniques, the review concludes by highlighting the significance of taking into account the possible hazards and benefits of nanomaterials for pest management and the necessity of an integrated approach. It also emphasizes the importance of more investigation into the behavior and environmental fate of nanomaterials to guarantee their safe and efficient application in agriculture.
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Agricultura , Nanoestruturas , Praguicidas , Controle de Pragas/métodos , Nanotecnologia , Humanos , Proteção de CultivosRESUMO
Stag beetles, recognized as common saproxylic insects, are valued for their vibrant coloration and distinctive morphology. These beetles play a crucial ecological role in decomposition and nutrient cycling, serving as a vital functional component in ecosystem functioning. Although previous studies have confirmed that stag beetles are predominantly fungivores, the fluctuations in their intestinal fungal communities at different developmental stages remain poorly understood. In the current study, high-throughput sequencing was employed to investigate the dynamic changes within intestinal fungal communities at various developmental stages in the stag beetle Dorcus hopei. Results showed that microbial diversity was higher during the larval stage than during the pupal and adult stages. Furthermore, significant differences were identified in the composition of the intestinal fungal communities across the larval, pupal, and adult stages, suggesting that developmental transitions may be crucial factors contributing to variations in fungal community composition and diversity. Dominant genera included Candida, Scheffersomyces, Phaeoacremonium, and Trichosporon. Functional predictions indicated a greater diversity and relative abundance of endosymbiotic fungi in the larval gut, suggesting a potential dependency of larvae on beneficial gut fungi for nutrient acquisition. Additionally, the application of abundance-based ß-null deviation and niche width analyses revealed that the adult gut exerted a stronger selection pressure on its fungal community, favoring certain taxa. This selection process culminates in a more robust co-occurrence network of fungal communities within the adult gut, thereby enhancing their adaptability to environmental fluctuations. This study advances our understanding of the intestinal fungal community structure in stag beetles, providing a crucial theoretical foundation for the development of saproxylic beetle resources, biomass energy utilization, plastic degradation strategies, and beetle conservation efforts.
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Besouros , Fungos , Microbioma Gastrointestinal , Larva , Animais , Besouros/microbiologia , Besouros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/microbiologia , Fungos/genética , Fungos/classificação , Fungos/fisiologia , Pupa/crescimento & desenvolvimento , Pupa/microbiologia , Micobioma , Biodiversidade , Simbiose , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
The transmission of plant viruses from infected to healthy host plants is a process in which insects play a major role, using various transmission strategies. Environmental factors have an impact on the transmission of viruses and the subsequent development of infections or diseases. When viruses are successful, plant virus diseases can reach epidemic proportions. Many plants across different regions are vulnerable to viral infections transmitted by the whitefly vector. Begomoviruses, which are transmitted by whiteflies, represent a significant threat to agriculture worldwide. The review highlights the mechanisms of virus acquisition and transmission by whiteflies and explores the factors influencing these interactions. Understanding the impacts of these changes is crucial for managing the spread of pests and mitigating damage to crops. It underscores the need for continued research to elucidate the mechanisms driving plant-insect-virus interactions and to identify new approaches for sustainable pest management.
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The global biomass production from agricultural farmlands is facing severe constraints from abiotic stresses like soil salinization. Salinity-mediated stress triggered the overproduction of reactive oxygen species (ROS) that may result in oxidative burst in cell organelles and cause cell death in plants. ROS production is regulated by the redox homeostasis that helps in the readjustment of the cellular redox and energy state in plants. All these cellular redox related functions may play a decisive role in adaptation and acclimation to salinity stress in plants. The use of nanotechnology like nanoparticles (NPs) in plant physiology has become the new area of interest as they have potential to trigger the various enzymatic and non-enzymatic antioxidant capabilities of plants under varying salinity levels. Moreover, NPs application under salinity is also being favored due to their unique characteristics compared to traditional phytohormones, amino acids, nutrients, and organic osmolytes. Therefore, this article emphasized the core response of plants to acclimate the challenges of salt stress through auxiliary functions of ROS, antioxidant defense system and redox homeostasis. Furthermore, the role of different types of NPs mediated changes in biochemical, proteomic, and genetic expressions of plants under salt stress have been discussed. This article also discussed the potential limitations of NPs adoption in crop production especially under environmental stresses.
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Antioxidantes , Nanopartículas , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteômica , Estresse Oxidativo , Plantas/metabolismo , Estresse Salino , Nanopartículas/toxicidade , SalinidadeRESUMO
Cadmium (Cd) contamination is considered as a widespread concern at global scale which is serious threats to human health. Phytoremediation is an eco-friendly approach which can remove or immobilize Cd from the soil. Different organic and inorganic amendments can potentially enhance Cd phytoremediation efficiency but the comparison of farmyard manure (FM), elemental sulphur (S) and ethylenediaminetetraacetic acid (EDTA) for Cd phytoremediation through spider plants (Chlorophytum comosum L.) remained unanswered. The present study evaluated the efficiency of S (0.1 and 0.2%), EDTA (0.1 and 0.2%, represented as EDTA-0.1 and EDTA-0.2) and FM (0.5 and 1%, represented as FM-0.5 and FM-1) for remediation of Cd contaminated soils (50 and 100 mg kg-1, represented as Cd-50 and Cd-100) through spider plants. Results depicted that the highest shoots and roots dry biomass was found in FM treated plants followed by S, EDTA and control except in EDTA-0.2 treatment in which the lowest values of these parameters were observed. Application of FM-1 significantly increased the shoot dry weight (120%), root dry weight (99%), as well as photosynthetic attributes in Cd-50 as compared to control. Application of EDTA-0.2 increased the bioavailable fraction of Cd than control and the maximum increase was observed in Cd-100. The highest Cd concentrations in shoot and roots were found in EDTA treated plants followed by S, control and FM irrespective of Cd and amendment levels. Maximum Cd in roots (109%) and shoots (156%) was recorded in plants grown in Cd-100 with EDTA-0.2 than control. The maximum bioaccumulation factor, translocation index, harvest index and root to shoot translocation were observed with EDTA than control and other treatments. EDTA along with spider plants may enhance the uptake of Cd but lower biomass production in the highest dose of EDTA may questioned the efficiency of EDTA.
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Cádmio , Poluentes do Solo , Humanos , Ácido Edético/farmacologia , Esterco , Poluentes do Solo/análise , Biodegradação Ambiental , Solo , Enxofre/farmacologiaRESUMO
A case study was conducted to evaluate the microplastics and heavy metals distribution in Pakistani farmland. Wastewater, soil, and vegetable samples were collected from four locations that received raw effluents for irrigation in the Faisalabad district. The average MPs abundances found in soil was 2790.75 items/kg, FSD-S has higher MPs (3865 items/kg) which is almost 34.62% from the total. However, the highest metal pollution (3.666 mg/kg) was recorded in the FSD-E zone, Cr showed the highest transfer factor about 34.24% in FSD-N in comparison with other sites. This research establishes a benchmark for estimating the environmental harm posed by microplastics and heavy metals in this rapidly emerging field of study.
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Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Metais Pesados/análise , Microplásticos , Plásticos , Solo , Poluentes do Solo/análiseRESUMO
Tobacco cutworm, Spodoptera litura Feb. (Lepidoptera; Noctuidae) is a notorious cosmopolitan pest of numerous crops. Frequent evolution of insecticide resistance and polyphagous nature favors the survival of this voracious pest. Nanotechnology offers an alternative technique to overcome the limitations of existing pest management strategies. In the present study, the silver nanoparticles were synthesized from Ocimum basilicum leaf extract and UV-spectra at 464.17 nm confirmed their synthesis while crystalline nature of nanoparticles was evaluated by X-rays diffraction (XRD) pattern and scanning electron microscopy (SEM) revealed their octagonal to spherical shape. Insecticidal potential of O. basilicum synthesized silver nanoparticles (ObAgNPs) was evaluated in comparison with some synthetic insecticides owning different mode of actions, including Coragen®, Proclaim®, Tracer® and Talstar® against S. litura. Probit analysis of 2nd, 3rd, 4th and 5th instars of S. litura showed that lethal concentrations (LCs) of tested nanoparticles and pesticides were positively correlated with older instars. All values of LC50, LC90 and LC95 were statistically different from each other with maximum on the 4th instar and minimum on 2nd instar of S. litura. Tukey's HSD test revealed that ObAgNPs caused maximum mortality (21.67-96.67%) in 2nd instar larvae at the rate of 100-1500 mg/L followed by Coragen® (18.33-91.67%), Proclaim® (13.33-78.33%) and Talstar® (13.33-68.33%), while Tracer indicated the lowest larval mortality (11.67-66.67%) at the rate of 60-120 mg/L and a similar trend was assessed for all the successive instars of S. litura. Higher activity of carboxyl esterase and glutathione-s-transferases confirmed the development of insecticide resistance against the synthetic chemicals. Conclusively, ObAgNPs were found to be eco-friendly but the most effective biogenic compounds for the suppression of S. litura population as compared to the selected synthetic chemicals which may be hazardous for the environment as well as human health. This study will assist the pesticide industries to re-standardize the dose rates against Spodoptera litura.