RESUMO
The herbicide glyphosate is widely used in agricultural practices around the world, can reach aquatic environments, and potentially impact non-target organisms. This study aimed to investigate the effects of glyphosate exposure (both as the active ingredient and its formulated product) on sperm quality, fertilization success, and development of pejerrey (Odontesthes bonariensis), a native freshwater fish species from Argentina. Results revealed a statistically significant increase in sperm motility at the highest concentration of the formulated product. In contrast, exposure to the active ingredient resulted in a decrease in certain motility parameters. Fertilization assays and embryonic development showed no notable effects in exposed groups. There were no effects in the morphology or temporal evolution of the embryonic stages, nor in the hatching rate. In contrast, larvae exposed to the formulated product exhibited a significant increase in mortality rates, reaching 100% mortality at the highest concentration within a few hours. These findings suggest differential susceptibility between embryos and larvae to glyphosate exposure and highlight the importance of simultaneously assessing the impacts of both the active ingredient and the entire formulation of glyphosate on freshwater fish reproduction and development.
Assuntos
Fertilização , Peixes , Glicina , Glifosato , Herbicidas , Larva , Motilidade dos Espermatozoides , Poluentes Químicos da Água , Animais , Herbicidas/toxicidade , Glicina/análogos & derivados , Glicina/toxicidade , Peixes/fisiologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Fertilização/efeitos dos fármacos , Masculino , Poluentes Químicos da Água/toxicidade , Larva/efeitos dos fármacos , Argentina , Espermatozoides/efeitos dos fármacosRESUMO
Glyphosate-based herbicides are the most widely agrochemicals used in the world. This toxic compound reaches aquatic ecosystems and can affect microalgae, which are the basis of the trophic web and the main primary producers in these environments. We tested the sensitivity of two species of green algae (Chlorophyta) to a glyphosate-based herbicide (Roundup Transorb) and the effect of contamination history in population rescue. Strains of Desmodesmus communis and Pseudopediastrum boryanum were tested in isolation and in co-occurrence in a two-step experiment, with three and 10 days each, respectively. In the first step, we exposed populations of the two species to Roundup Transorb at 0, 350, 500, and 1000 µgâ§L-1 glyphosate. Next, we transferred aliquots of each treatment to a new media where 20,000 µgâ§L-1 of the glyphosate-based herbicide was added. Growth inhibition at the end of Step 1 was dose-dependent regardless of species and whether they were isolated or combined. Rescue after exposure to 20,000 µgâ§L-1 of the glyphosate-based herbicide for three and 10 days was more successful for populations previously exposed to intermediate concentrations of 350 and 500 µgâ§L-1. We suggest that these concentrations triggered a process that increased algal tolerance to the glyphosate-based herbicide. In addition, neither the species nor the fact that they were isolated or combined influenced glyphosate-based herbicide toxicity, at least for the concentrations tested in this study.
Assuntos
Água Doce , Glicina , Glifosato , Herbicidas , Microalgas , Poluentes Químicos da Água , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Microalgas/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Clorófitas/efeitos dos fármacosRESUMO
Polymer-based herbicide nanocarriers have shown potential for increasing the herbicide efficacy and environmental safety. This study aimed to develop, characterize, and evaluate toxicity to target and nontarget organisms of natural-based polymeric nanosystems for glyphosate. Polymers such as chitosan (CS), zein (ZN), and lignin (LG) were used in the synthesis. Nanosystem size, surface charge, polydispersity index, encapsulation efficiency, toxicity to weed species (Amaranthus hybridus, Ipomoea grandifolia, and Eleusine indica), and Roundup Ready (RR) crops, soil respiration, and enzyme activity were evaluated. The most stable system was the combination of ZN with the cross-linker poloxamer (PL), with higher weed control efficacy (90-96%) for A. hybridus, compared to commercial glyphosate (40%). No improvement was observed for I. grandifolia and E. indica. No glyphosate toxicity was observed in RR crops, soil respiration, or soil enzymes, indicating no toxic effects of the nanoformulation in these models. ZN-PL systems can be a promising alternative for glyphosate delivery, using environmentally friendly materials, with improved efficiency for weed control in agriculture.
Assuntos
Portadores de Fármacos , Glicina , Glifosato , Herbicidas , Glicina/análogos & derivados , Glicina/química , Glicina/toxicidade , Glicina/farmacologia , Herbicidas/química , Herbicidas/farmacologia , Portadores de Fármacos/química , Amaranthus/efeitos dos fármacos , Amaranthus/química , Controle de Plantas Daninhas , Eleusine/química , Eleusine/efeitos dos fármacos , Agricultura , Plantas Daninhas/efeitos dos fármacos , Polímeros/química , Quitosana/química , Nanopartículas/química , Zeína/química , Lignina/químicaRESUMO
Initially, products based on glyphosate (GLY) were considered non-toxic or slightly toxic to bees. Still, recent research has shown that these products can cause mortality or trigger sublethal effects in these insects. Roundup Transorb R® (RT) is one of the GLY-based formulations sold in Brazil. It is used in several crops, and studies are required on its toxicity to honey bees. Thus, the objective of this work was to evaluate, under laboratory conditions, the lethal and sublethal effects of RT for adult workers (foragers) of Africanized A. mellifera. For this, two bioassays were carried out with Africanized honey bees. The experimental design was completely randomized, consisting of five treatments (T0 - control, T25 - 25â¯% GLY, T50 - 50â¯% GLY, T75 - 75â¯% GLY, and T100 GLY - 100â¯% recommended dose). The bioassays were carried out as follows: (1) Acute oral and topical exposure, evaluating mortality, effects on flight capacity, vertical displacement, and locomotion (in the latter only for oral contamination), consisting of five repetitions and 10 honey bees per repetition; (2) Chronic exposure via the oral route and spraying, assessing mortality, for both contamination routes and damage to the midgut epithelium thickness when contaminated via the oral route, composed of five replicates and 20 honey bees per replicate. The results showed that chronic oral exposure to RT can increase honeybee mortality and damage the thickness of their midgut epithelium. In addition, when acutely exposed orally, the honey bees had reduced walking ability. RT did not affect the other evaluated parameters. Thus, it is concluded that the RT-formulated GLY can affect the survival, midgut morphology, and behavior of A. mellifera.
Assuntos
Glicina , Glifosato , Herbicidas , Animais , Glicina/análogos & derivados , Glicina/toxicidade , Abelhas/efeitos dos fármacos , Herbicidas/toxicidade , BrasilRESUMO
Glyphosate-based herbicides are extensively utilized in Neotropical agriculture for weed control. Despite their widespread application, concerns regarding water contamination and its consequential impacts on aquatic organisms persist. Notably, there remains a dearth of studies investigating the effects of glyphosate on Neotropical fish species. This study aimed to address this gap by investigating the morphophysiological effects of this herbicide on the liver, gills, and ovaries of Astyanax altiparanae, an ecological and economically important neotropical fish species. Forty individuals were acclimated for 15 days before being exposed to different concentrations of glyphosate (65, 280, and 1000 µg/L) for 28 days. Histological and histometric analyses were conducted on liver, gill, and ovary samples. The findings revealed significant alterations in fish physiology following exposure to glyphosate. The hepatosomatic index increased markedly across all concentration levels, accompanied by dilation of hepatic sinusoidal capillaries, particularly pronounced at higher concentrations. Gill samples exhibited congestion in the central venous sinus, lamellar fusion, and cell death. Additionally, the exposed fish showed a decrease in gonadosomatic index, and the mature females an increase in pre-vitellogenic follicles and a decrease in vitellogenic follicles. This study detected adverse morphophysiological impacts of glyphosate-based herbicides on A. altiparanae, even at permitted concentrations. These findings emphasize the necessity for further research and improved management strategies to mitigate environmental risks associated with herbicide use in aquatic ecosystems.
Assuntos
Brânquias , Glicina , Glifosato , Herbicidas , Fígado , Ovário , Poluentes Químicos da Água , Animais , Herbicidas/toxicidade , Herbicidas/farmacologia , Glicina/análogos & derivados , Glicina/toxicidade , Glicina/farmacologia , Feminino , Fígado/efeitos dos fármacos , Ovário/efeitos dos fármacos , Brânquias/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Characidae/fisiologiaRESUMO
Eucalyptus stands out as one of the most productive tree species for large-scale cultivation. However, like all cultivated crops, it requires specialized management practices, including the control of weeds, pathogens, and pests. Glyphosate is the most widely applied herbicide used in the essential weeding effort, and it ensures the sustainable management of eucalyptus cultivation in Brazil. Given the sensitivity of eucalyptus to glyphosate, existing weed control methods in young eucalyptus farms predominantly rely on protected mechanical or/and knapsack spraying. Both methods contribute to herbicide drift, which compromises tree yield and increases chemical waste due to uneven spraying. This study provides a detailed observation of the physiological parameters and long-term field performance of glyphosate-tolerant (HT), genetically modified (GM) eucalyptus developed by FuturaGene/Suzano S.A. and approved in Brazil for operational deployment. The HT GM eucalyptus events were meticulously evaluated to ensure high levels of glyphosate tolerance. This involved the direct application of herbicide on seedlings in greenhouse studies and on young trees in field conditions. The herbicide-treated GM eucalyptus in all trials demonstrated consistent growth and maintained physiological parameters comparable to their respective non-sprayed wild-type (WT) counterparts. The HT GM eucalyptus represents a significant advancement by enabling the direct application of glyphosate over the top of the trees to control the weeds within the planting row. This innovative approach minimizes the need for frequent mechanical and manual interventions, thereby lowering worker herbicide exposure, reducing the environmental impact of mechanical operations, and enhancing the overall efficiency and sustainability of HT GM eucalyptus stands.
Assuntos
Eucalyptus , Glicina , Glifosato , Resistência a Herbicidas , Herbicidas , Plantas Geneticamente Modificadas , Eucalyptus/genética , Eucalyptus/efeitos dos fármacos , Eucalyptus/crescimento & desenvolvimento , Glicina/análogos & derivados , Glicina/farmacologia , Glicina/toxicidade , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Herbicidas/farmacologia , Resistência a Herbicidas/genética , Brasil , Controle de Plantas Daninhas/métodosRESUMO
Digitaria insularis poses a significant challenge in weed control due to its perennial habit, dense clumping growth, and the widespread presence of herbicide-resistant biotypes. Our research investigates whether single or multiple herbicide resistance biotypes of D. insularis experience fitness costs, specifically affecting their germination. To determine the resistance factor, a dose-response curve was employed using glyphosate and haloxyfop-P-methyl herbicides separately in a completely randomized design (CRD) with four replicates per dose (nine doses total). Shoot dry mass was measured at 100 days after herbicide application (DAA), with control assessments performed at 14, 28, and 42 DAA. Subsequently, a separate CRD experiment examined the germination rate as a function of temperature and photoperiod for each biotype. This factorial scheme tested six temperatures across three biotypes (susceptible and two resistant types) under three light exposure periods (0, 8, and 12 hours). Germination percentage and the germination speed index (GSI) were calculated for 14 days, with counts of healthy seedlings recorded daily. Statistical analysis confirmed the resistance/susceptibility of the biotypes based on the dose-response curve. For the susceptible and simple resistance biotypes, the most favorable temperatures for germination were 20, 30 and 40 °C, at which the highest germination percentages and a higher germination speed index were observed. On the other hand, for the biotype with multiple resistance, the temperatures of 25, 30 and 35 °C were more favorable, promoting superior results in both parameters studied.
Assuntos
Digitaria , Germinação , Glicina , Glifosato , Resistência a Herbicidas , Herbicidas , Germinação/efeitos dos fármacos , Germinação/fisiologia , Herbicidas/farmacologia , Digitaria/efeitos dos fármacos , Digitaria/fisiologia , Glicina/análogos & derivados , Glicina/farmacologia , Temperatura , Fatores de Tempo , Relação Dose-Resposta a DrogaRESUMO
Glyphosate stands out in the eucalyptus management, which makes it essential to know its behavior, its effects on the plant, and possible environmental impacts. This study aimed to identify and quantify the root exudation of glyphosate and aminomethylphosphonic acid (AMPA) by Eucalyptus urophylla with chromatographic and biological methods. The five glyphosate doses were tested (0, 360, 720, 1080 and 1440 g a.e ha-1) on E. urophylla plants. The physiological and intoxication evaluations were performed after herbicide application. Water samples remaining from the pots were used for chemical quantification of root exudation of glyphosate and AMPA in high-performance liquid chromatography. Cucurbita pepo plants were used as bioindicators of glyphosate in the water remaining in the pots after applying herbicide. The increase in glyphosate doses promoted linear growth in E. urophylla intoxication and significantly reduced total dry mass and root production. E. urophylla plants had their photosynthetic, transpiratory, and stomatal conductance rates reduced as the herbicide doses increased. The AMPA root exudation was not detected, but it was possible to identify the presence of glyphosate by bioassay and chemical methods. Root exudation of glyphosate by eucalyptus can result in lesser herbicide action in plant control and cause contamination of deeper soil layers.
Assuntos
Eucalyptus , Glicina , Glifosato , Herbicidas , Raízes de Plantas , Eucalyptus/metabolismo , Eucalyptus/crescimento & desenvolvimento , Glicina/análogos & derivados , Glicina/toxicidade , Glicina/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/química , Herbicidas/metabolismo , Organofosfonatos/metabolismo , Cucurbita/metabolismo , Cucurbita/crescimento & desenvolvimento , Cucurbita/efeitos dos fármacosRESUMO
This research proposes an alternative method to detect and quantify glyphosate residues in unroasted green coffee beans by LC-MS/MS. The sample preparation was conducted without derivatization steps, with integrated cleanup, which improves the analytical method's frequency. Validation results were consistent with the requirements of the regulatory guidelines employed. Specificity, linearity (r2 = 0.9991), precision (RSD ≤ 9%), and recovery (92-112%) were ensured, with a satisfactory limit of quantification (LOQ = 0.48 mg kg-1). These data demonstrate that the method is suitable for monitoring glyphosate residues in unroasted coffee beans while offering simplicity and speed in sample preparation. The method was applied to analyze authentic unroasted coffee bean samples, in which two of them were contaminated with glyphosate (
Assuntos
Coffea , Contaminação de Alimentos , Glicina , Glifosato , Herbicidas , Sementes , Espectrometria de Massas em Tandem , Glicina/análogos & derivados , Glicina/análise , Espectrometria de Massas em Tandem/métodos , Coffea/química , Contaminação de Alimentos/análise , Sementes/química , Herbicidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Praguicidas/análise , Cromatografia Líquida/métodos , Café/química , Espectrometria de Massa com Cromatografia LíquidaRESUMO
The impact of environmental pollutants has been a focus of investigation in recent years. Studies assessing the effects of these pollutants are essential for understanding the challenges faced by non-target species. Among the many substances used for agricultural purposes, the herbicide glyphosate is one of the most widely marketed in recent years. This broad-spectrum herbicide is commonly used to protect a variety of crops. In this study, we evaluated the effects of chronic glyphosate exposure on a native amphibian species, Physalaemus gracilis. Amphibians, which develop in aquatic environments, are highly sensitive to pesticides. Because of this, we investigated morphological, physiological, behavioral, and biochemical parameters in the early stages of development. The animals were exposed to environmentally relevant concentrations of a glyphosate-based herbicide (0, 100, 350, and 700 µg L⻹) during their first seven days of life. As a result, we observed impairments in anti-predatory behavior, reduced body mass index, and scaled mass index, malformations of the mouth and intestine, increased acetylcholinesterase activity, cardiotoxicity, and oxidative stress. These findings underscore the importance of studying native non-target species and highlight the need to evaluate the effects of environmentally relevant concentrations, as well as to review legislation regarding permissible levels of glyphosate in surface water and public water supplies.
Assuntos
Glicina , Glifosato , Herbicidas , Glicina/análogos & derivados , Glicina/toxicidade , Animais , Herbicidas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismoRESUMO
Glyphosate (GLY), a globally-used organophosphate herbicide, is frequently detected in various environmental matrices, including water, prompting significant attention due to its persistence and potential ecological impacts. In light of this environmental concern, innovative remediation strategies are warranted. This study utilized Serratia sp. AC-11 isolated from a tropical peatland as a biocatalyst in a microbial fuel cell (MFC) coupled with a homogeneous electron-Fenton (EF) process to degrade glyphosate in aqueous medium. After coupling the processes with a resistance of 100 Ω, an output voltage value of 0.64 V was obtained and maintained stable throughout the experiment. A bacterial biofilm of Serratia sp. AC-11 was formed on the carbon felt electrode, confirmed by attenuated total reflectance-Fourier transformed infrared (ATR-FTIR) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). In the anodic chamber, the GLY biodegradation rate was 100% after 48 h of experimentation, with aminomethylphosphonic acid (AMPA) remaining in the solution. In the cathodic chamber, the GLY degradation rate for the EF process was 69.5% after 48 h experimentation, with almost all of the AMPA degraded by the in situ generated hydroxyl radicals. In conclusion, the results demonstrated that Serratia sp. AC-11 not only catalyzed the biodegradation of glyphosate but also facilitated the generation of electrons for subsequent transfer to initiate the EF reaction to degrade glyphosate. This dual functionality emphasizes the unique capabilities of Serratia sp. AC-11, it as an electrogenic microorganism with application in innovative bioelectrochemical processes, and highlighting its role in sustainable strategies for environmental remediation.
Assuntos
Biodegradação Ambiental , Fontes de Energia Bioelétrica , Glifosato , Serratia , Serratia/metabolismo , Herbicidas/metabolismo , Glicina/análogos & derivados , Glicina/metabolismo , Glicina/química , Poluentes Químicos da Água/metabolismo , EletrodosRESUMO
Correct interpretation of the pathogenicity of germline RUNX1 variants is essential for FPD/AML diagnosis, clinical management and leukaemia surveillance. We report two families with clear FPD/AML phenotypic features harbouring missense variants at RHD critical residue Gly168. Although classified as of unknown significance (VUS) by RUNX1-specific curation guidelines, these variants should rather be considered likely pathogenic, as supported by computational tools, structural modelling and dysregulated platelet expression of RUNX1-targets, adding Gly168 among amino acids currently recognised as mutational hotspots. Our data could help reduce the number of variants classified as VUS, providing evidence for updating RUNX1 guidelines, thus improving FPD/AML diagnosis.
Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core , Glicina , Leucemia Mieloide Aguda , Mutação de Sentido Incorreto , Humanos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Masculino , Glicina/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Linhagem , Transtornos Plaquetários/genética , Transtornos Plaquetários/diagnóstico , Adulto , Substituição de Aminoácidos , Transtornos Herdados da Coagulação SanguíneaRESUMO
Hymenaea stigonocarpa Mart. ex Hayne has leaves with adaxial and abaxial epidermis covered by a very thick cuticle, in addition to anatomical structures involved in reducing the amount of herbicide absorbed by plants. Thus, we tested the hypothesis that H. stigonocarpa is potentially resistant to the herbicide glyphosate, exposing the plants to different doses (0, 96, 240, 480, and 960 g a.e ha-1). We carried out assessments of the symptoms, anatomy, growth and physiology of the plants and found that exposure to glyphosate negatively affected the height and number of leaves of the plants. Leaf fall resulted in a reduction in the photosynthetic capacity of plants, which responded by investing in stem diameter. Despite this, no visual symptoms of glyphosate toxicity were observed at the concentrations evaluated and histochemical tests did not detect signs of oxidative stress in the leaves, nor starch accumulation, indicating that carbohydrate translocation was not impaired. These results confirm our hypothesis of tolerance of H. stigonocarpa to glyphosate. Furthermore, plants exposed to the lowest doses of glyphosate (96 and 240 g ha-1) showed good growth, photosynthesis, transpiration and photochemical potential responses, indicating a hormetic effect in this application range.
Assuntos
Glicina , Glifosato , Herbicidas , Fotossíntese , Glicina/análogos & derivados , Glicina/toxicidade , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/química , Resistência a HerbicidasRESUMO
The potential neurotoxicity of environmental contaminants, such as pesticides, is implicated in the etiology of neurodevelopmental disorders, particularly given the heightened vulnerability of the developing brain. Among these contaminants, glyphosate, a widely used herbicide, has been linked to alterations in neurodevelopment, though its precise neurotoxic mechanisms are not fully elucidated. In this context, our systematic review evaluates the impact of maternal exposure to glyphosate alone (GLY) or glyphosate-based-herbicide (GBH) on neurodevelopmental and behavioral outcomes in rodent offspring. This assessment encompasses a comprehensive examination of behavioral, biochemical, morphological, and genetic alterations resulting from perinatal glyphosate exposure. The Systematic review protocol was registered in the platform Open Science Framework (OSF) following the guidelines of the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE). Our analysis demonstrate that glyphosate disrupts redox signaling, metabolic pathways, and neurotransmitter systems, thereby affecting brain architecture and function across genders and developmental stages in rodents. The results of this review elucidate the extensive neurochemical and behavioral disruptions attributed to glyphosate, highlighting the critical need for advanced neurodevelopmental risk assessment methodologies. Such refined evaluations are vital to inform targeted prevention and intervention strategies in the context of environmental neurotoxicants.
Assuntos
Glicina , Glifosato , Herbicidas , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Roedores , Glicina/análogos & derivados , Glicina/toxicidade , Animais , Feminino , Herbicidas/toxicidade , Gravidez , Transtornos do Neurodesenvolvimento/induzido quimicamente , Poluentes Ambientais/toxicidade , Ratos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/crescimento & desenvolvimento , CamundongosRESUMO
The unregulated use and improper management of herbicides can cause negative effects on non-target species and promote changes in biological communities. Therefore, the current study is aimed at understanding morphoanatomical responses and effects on seedling development induced by the herbicides glyphosate and saflufenacil in Enterolobium contortisiliquum, a non-target tropical species. The plants were cultivated in a greenhouse and subjected to herbicides at doses of 0, 160, 480, and 1440 g a.e ha-1 for glyphosate, and 0, 25, 50, and 100 g a.i ha-1 for saflufenacil. We conducted visual and morphological assessments over 90 days post-application. Leaf samples were collected 12 days after the application for anatomical analysis, and we also performed a micromorphometric analysis of the leaf tissues. Biomarkers of phytotoxicity were identified in plants exposed to both herbicides, even at the lowest doses, including in leaves without visual symptoms. The main morphological alterations were the decrease in growth, stem diameter, and dry mass. Furthermore, the leaves and stems visually exhibited chlorosis and necrosis. Both herbicides triggered anatomical modifications such as significant changes (p < 0.05) in the thickness of leaf tissues, hypertrophy, cell collapse, and changes in epicuticular waxes. However, the alterations induced by glyphosate were more widespread compared to saflufenacil, encompassing alterations in the root system. We confirmed that the different mechanisms of action of each herbicide and the existence of an underground reserve system in this species are intrinsically linked to the morphological and developmental responses described. Our findings suggest that E. contortisiliquum could be a potential bioindicator species for these herbicides in the environment, even at concentrations lower than those typically recommended for field application.
Assuntos
Fabaceae , Glicina , Glifosato , Herbicidas , Herbicidas/toxicidade , Glicina/análogos & derivados , Glicina/toxicidade , Fabaceae/efeitos dos fármacos , Árvores/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Pirimidinonas , SulfonamidasRESUMO
Phosphonates (PHTs), organic compounds with a stable C-P bond, are widely distributed in nature. Glyphosate (GP), a synthetic PHT, is extensively used in agriculture and has been linked to various human health issues and environmental damage. Given the prevalence of GP, developing cost-effective, on-site methods for GP detection is key for assessing pollution and reducing exposure risks. We adopted Agrobacterium tumefaciens CHLDO, a natural GP degrader, as a host and the source of genetic parts for constructing PHT biosensors. In this bacterial species, the phn gene cluster, encoding the C-P lyase pathway, is regulated by the PhnF transcriptional repressor. We selected the phnG promoter, which displays a dose-dependent response to GP, to build a set of whole-cell biosensors. Through stepwise genetic optimization of the transcriptional cascade, we created a whole-cell biosensor capable of detecting GP in the 0.25-50 µM range in various samples, including soil and water.
Assuntos
Agrobacterium tumefaciens , Técnicas Biossensoriais , Glicina , Glifosato , Organofosfonatos , Agrobacterium tumefaciens/genética , Técnicas Biossensoriais/métodos , Glicina/análogos & derivados , Glicina/farmacologia , Glicina/metabolismo , Organofosfonatos/metabolismo , Regiões Promotoras Genéticas/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Família Multigênica , LiasesRESUMO
Agrochemicals pose significant threats to the survival of bees, yet the physiological impacts of sublethal doses on stingless bees remain poorly understood. This study investigated the effects of acute oral exposure to three commercial formulations of agrochemicals [CuSO4 (leaf fertilizer), glyphosate (herbicide), and spinosad (bioinsecticide)] on antioxidant enzymes, malondialdehyde content (MDA), nitric oxide (NO) levels, and total hemocyte count (THC) in the stingless bee Partamona helleri. Foragers were exposed to lethal concentrations aimed to kill 5% (LC5) of CuSO4 (120 µg mL-1) or spinosad (0.85 µg mL-1) over a 24-h period. Glyphosate-exposed bees received the recommended label concentration (7400 µg mL-1), as they exhibited 100% survival after exposure. Ingestion of CuSO4 or glyphosate-treated diets by bees was reduced. Levels of NO and catalase (CAT) remained unaffected at 0 h or 24 h post-exposure. Superoxide dismutase (SOD) activity was higher at 0 h compared to 24 h, although insignificantly so when compared to the control. Exposure to CuSO4 reduced glutathione S-transferase (GST) activity at 0 h but increased it after 24 h, for both CuSO4 and glyphosate. MDA levels decreased after 0 h exposure to CuSO4 or spinosad but increased after 24 h exposure to all tested agrochemicals. THC showed no difference among glyphosate or spinosad compared to the control or across time. However, CuSO4 exposure significantly increased THC. These findings shed light on the physiological responses of stingless bees to agrochemicals, crucial for understanding their overall health.
Assuntos
Agroquímicos , Antioxidantes , Hemócitos , Animais , Abelhas/efeitos dos fármacos , Abelhas/fisiologia , Antioxidantes/metabolismo , Agroquímicos/toxicidade , Hemócitos/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Glicina/análogos & derivados , Glicina/toxicidade , Catalase/metabolismoRESUMO
Herbicide-resistant Conyza spp. are a threat to many crops. These widespread weeds are closely related species and often cooccur. To characterize the origins of their resistance and the mechanisms underlying their spread, we assessed the genomic variation in glyphosate-resistant Conyza spp. in Brazil. Twenty populations were sampled from soybean fields across four macroregions (MRSs). A genotyping-by-sequencing study resulted in 2,998 single-nucleotide polymorphisms (SNPs) obtained for C. bonariensis (L.) and the closely related C. sumatrensis (Retz) E. Walker. Higher genomic diversity (π) and heterozygosity (HO/HE) and lower inbreeding coefficient (FIS) values were detected in populations of Conyza spp. from MRS 1 (southern) than in those from other MRSs. Strong genomic structure clustered individuals into three groups (FST = 0.22; p value = 0.000) associated with the MRSs. Thus, resistance to glyphosate originated from independent selection in different MRSs across Brazil. Our dataset supports the occurrence of intraspecific gene flow in Brazil and identified individuals of C. bonariensis that did not group within species. These findings suggest that allelic introgressions within and among species have impacted the evolution and spread of resistance to glyphosate in Conyza spp. We discuss how to mitigate new resistance cases, particularly for the released stacked traits herbicide tolerance in soybeans.
Assuntos
Conyza , Fluxo Gênico , Glycine max , Glifosato , Resistência a Herbicidas , Polimorfismo de Nucleotídeo Único , Glycine max/genética , Glycine max/efeitos dos fármacos , Resistência a Herbicidas/genética , Conyza/genética , Conyza/efeitos dos fármacos , Brasil , Herbicidas/farmacologia , Glicina/análogos & derivados , Glicina/farmacologia , Genômica/métodosRESUMO
The study investigated guanidinoacetic acid (GAA) supplementation with varying dietary digestible arginine (Arg) and glycine+serine (Gly+Ser) concentrations in the starter phase, exploring respective carry-over effects on growth performance, blood chemistry, incidence of pectoral myopathies and proximate composition in broilers. A total of 2,800 one-day-old male broiler chicks were distributed in a central composite design with 2 factors and double experimental mesh, represented by supplementation or omission of 0.6 g per kg of GAA, with a central point represented by 107% of Arg and 147% of Gly+Ser, 4 factorial points (combinations of Arg/Gly+Ser concentrations: 96.4/132.5%; 117.6/132.5%; 96.4/161.5%, and 117.6/132.5%), and 4 axial points (combinations of axial points estimated for Arg and Gly+Ser, with the central points of 92/147%; 122/147%; 107/126.5, and 107/167.5%), totaling 18 treatments, 4 repetitions to factorial and axial points, 24 replicates to the central point, and 25 birds per pen. Feed conversion ratio (FCR) from d 1 to 10 had a linear response (P = 0.009) for the decreasing Arg content and a quadratic response (P = 0.047) for Gly+Ser concentrations. Broilers supplemented GAA had lower FCR compared with nonsupplemented groups from d 1 to 10 (P = 0.048) and d 1 to 42 (P = 0.026). Aspartate aminotransferase (AST) exhibited increasing and decreasing linear effects as a function of Arg (P = 0.008) and Gly+Ser (P = 0.020) concentrations, respectively. Guanidinoacetic acid decreased serum AST (P = 0.028). Guanidinoacetic acid reduced moderate + severe (P = 0.039) and mild (P = 0.015) Wooden Breast scores. The occurrence of normal White Striping increased (P = 0.002), while severe score was reduced (P = 0.029) with GAA supplementation. In conclusion, increased digestible Arg:Lys and 14% and 6% above the recommendations (107% and 147%), respectively, provided improved FCR during the starter phase. Dietary GAA supplementation (0.6 g per kg) improved FCR, reduced severity of breast myopathies and appears to have reduced muscle damage in broilers fed plant-based diets.
Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Arginina , Galinhas , Dieta , Suplementos Nutricionais , Glicina , Serina , Animais , Galinhas/fisiologia , Galinhas/crescimento & desenvolvimento , Glicina/análogos & derivados , Glicina/administração & dosagem , Glicina/farmacologia , Ração Animal/análise , Arginina/administração & dosagem , Arginina/farmacologia , Suplementos Nutricionais/análise , Dieta/veterinária , Masculino , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Serina/administração & dosagem , Serina/farmacologia , Distribuição Aleatória , Músculos PeitoraisRESUMO
As the most abundant pollinator insect in crops, Apis mellifera is a sentinel species of the pollinator communities. In these ecosystems, honey bees of different ages and developmental stages are exposed to diverse agrochemicals. However, most toxicological studies analyse the immediate effects during exposure. Late effects during adulthood after early exposure to pollutants during larval development are poorly studied in bees. The herbicide glyphosate (GLY) is the most applied pesticide worldwide. GLY has been detected in honey and beebread from hives near treated crops. Alterations in growth, morphogenesis or organogenesis during pre-imaginal development could induce late adverse effects after the emergence. Previous studies have demonstrated that GLY alters honey bee development, immediately affecting survival, growth and metabolism, followed by late teratogenic effects. The present study aims to determine the late impact on the behaviour and physiology of adult bees after pre-imaginal exposure to GLY. For that, we reared brood in vitro or in the hive with sub-chronic exposure to the herbicide with the average detected concentration in hives. Then, all newly emerged bees were reared in an incubator until maturity and tested when they became nurse-aged bees. Three behavioural responses were assessed as markers of cognitive and physiological impairment. Our results show i) decreased sensitivity to sucrose regardless of the rearing procedure, ii) increased choice latency and locomotor alterations during chemotaxis and iii) impaired associative learning. These late toxicity signs could indicate adverse effects on task performance and colony efficiency.