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1.
Molecules ; 27(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36364176

RESUMO

The synthesis of cyclotetrapeptides analogues of the natural products tentoxin and versicotide D was achieved in good yield by solid phase peptide synthesis (SPPS) of their linear precursors and solution phase cyclization. All the cyclopeptides and several open precursors were evaluated as herbicides. Five cyclopeptides and five lineal peptides showed a significant inhibition (>70%) of Ryegrass seed's radicle growth at 67 µg/mL. The evaluation at lower concentrations (4-11 µM) indicates two cyclopeptides analogs of tentoxin, which present one (N-Methyl-d-Phe), and two N-MeAA (N-Methyl-Ala and N-Methyl-Phe), respectively, as the most active of them, showing remarkable phytotoxic activity. In two cases, the open precursors are as active as their corresponding cyclopeptide. However, many linear peptides are inactive and their cyclization derivatives showed herbicidal activity. In addition, two cyclopeptide analogues of versicotide D showed more improved activity than the natural product. The results indicate that the peptide sequence, the amino acid stereochemistry and the presence of N-methyl group have important influence on the phytotoxic activity. Moreover, several compounds could be considered as lead candidates in the development of bioherbicides.


Assuntos
Produtos Biológicos , Herbicidas , Produtos Biológicos/farmacologia , Herbicidas/farmacologia , Ciclização , Peptídeos Cíclicos/química , Técnicas de Síntese em Fase Sólida
2.
J Agric Food Chem ; 70(45): 14352-14366, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36326728

RESUMO

Diuron [DU; 3-(3,4-dichlorophenyl)-1,1-dimethylurea], a widely used herbicide for weed control, arouses ecological and health risks due to its environment persistence. Our findings revealed that DU at 0.125-2.0 mg L-1 caused oxidative damage to rice. RNA-sequencing profiles disclosed a globally genetic expression landscape of rice under DU treatment. DU mediated downregulated gene encoding photosynthesis and biosynthesis of protein, fatty acid, and carbohydrate. Conversely, it induced the upregulation of numerous genes involved in xenobiotic metabolism, detoxification, and anti-oxidation. Furthermore, 15 DU metabolites produced by metabolic genes were identified, 7 of which include two Phase I-based and 5 Phase II-based derivatives, were reported for the first time. The changes of resistance-related phytohormones, like JA, ABA, and SA, in terms of their contents and molecular-regulated signaling pathways positively responded to DU stress. Our work provides a molecular-scale perspective on the response of rice to DU toxicity and clarifies the biotransformation and degradation fate of DU in rice crops.


Assuntos
Herbicidas , Oryza , Diurona/metabolismo , Oryza/genética , Oryza/metabolismo , Herbicidas/farmacologia , Herbicidas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Estresse Oxidativo , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Sci Rep ; 12(1): 18893, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344537

RESUMO

Glyphosate is the most used herbicide worldwide, and is an important source of economical weed control in glyphosate-resistant crops, and conservation tillage systems, among other uses. Downy brome (Bromus tectorum L.), otherwise known as cheatgrass, is a highly invasive winter-annual grass weed in cropping systems, pastureland, and naturalized or ruderal areas in western North America. In 2021, a downy brome population remained uncontrolled following four applications of glyphosate in a glyphosate-resistant canola (Brassica napus L.) field located in Taber County, Alberta, Canada. All individuals from the subsequent generation of the population survived glyphosate treatment at the typical field rate (900 g ae ha-1). In dose-response bioassays, the putative glyphosate-resistant population exhibited 10.6- to 11.9-fold, 7.7- to 8.7-fold, 7.8- to 8.8-fold, and 8.3- to 9.5-fold resistance to glyphosate based on plant survival, visible control, and biomass fresh weight and dry weight, respectively, compared with two susceptible populations 21 days after treatment. Estimated glyphosate rates for 80% control of this population ranged from 2795 to 4511 g ae ha-1; well above common usage rates. This downy brome population represents the first glyphosate-resistant grass weed confirmed in Canada, and the second weed species exhibiting glyphosate resistance in the Canadian prairie region.


Assuntos
Brassica napus , Herbicidas , Humanos , Bromus , Glicina/farmacologia , Controle de Plantas Daninhas , Herbicidas/farmacologia , Alberta , Resistência a Herbicidas/genética
4.
Genes (Basel) ; 13(11)2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36360259

RESUMO

Herbicides have become one of the most widespread weed-control tools in the world since their advent in the mid-20th century [...].


Assuntos
Resistência a Herbicidas , Herbicidas , Resistência a Herbicidas/genética , Plantas Daninhas/genética , Controle de Plantas Daninhas , Herbicidas/farmacologia
5.
Sci Rep ; 12(1): 18258, 2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309535

RESUMO

GBHs are the most widely used herbicides for weed control worldwide that potentially affect microorganisms, but the role of their sublethal exposure in the development of antibiotic resistance of Pseudomonas aeruginosa is still not fully investigated. Here, the effects of glyphosate acid (GLY), five glyphosate-based herbicides (GBHs), and POE(15), a formerly used co-formulant, on susceptibility to imipenem, a potent carbapenem-type antibiotic, in one clinical and four non-clinical environmental P. aeruginosa isolates were studied. Both pre-exposure in broth culture and co-exposure in solid media of the examined P. aeruginosa strains with 0.5% GBHs resulted in a decreased susceptibility to imipenem, while other carbapenems (doripenem and meropenem) retained their effectiveness. Additionally, the microdilution chequerboard method was used to examine additive/antagonistic/synergistic effects between GLY/POE(15)/GBHs and imipenem by determining the fractional inhibitory concentration (FIC) indexes. Based on the FIC index values, glyphosate acid and Total demonstrated a potent antagonistic effect in all P. aeruginosa strains. Dominator Extra 608 SL and Fozat 480 reduced the activity of imipenem in only one strain (ATCC10145), while POE(15) and three other GBHs did not have any effect on susceptibility to imipenem. Considering the simultaneous presence of GBHs and imipenem in various environmental niches, the detected interactions between these chemicals may affect microbial communities. The mechanisms of the glyphosate and GBH-induced imipenem resistance in P. aeruginosa are yet to be investigated.


Assuntos
Herbicidas , Pseudomonas aeruginosa , Imipenem/farmacologia , Herbicidas/farmacologia , Glicina/farmacologia , Carbapenêmicos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Testes de Sensibilidade Microbiana
6.
Int J Mol Sci ; 23(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36293032

RESUMO

Beckmannia syzigachne is a noxious grassy weed that infests wheat fields in China. Previously, we identified that mesosulfuron-methyl resistance in a B. syzigachne population (R, SD04) was conferred by non-target resistance, such as cytochrome P450 mixed-function oxidases (P450s)-based metabolism. RNA sequencing and real-time PCR (qRT-PCR) were used to discover potential P450s-resistant-related genes. Five cytochrome P450s (CYP704A177, CYP96B84, CYP71D7, CYP93A1, and CYP99A44) were found to be highly expressed in R plants. In this study, CYP99A44 and CYP704A177 were cloned from B. syzigachne and transferred into Arabidopsis thaliana to test the sensitivity of Arabidopsis with and without P450s genes to mesosulfuron-methyl and other acetolactate synthase (ALS)-inhibiting herbicides. Transgenic Arabidopsis overexpressing CYP99A44 became resistant to the sulfonylurea herbicide mesosulfuron-methyl, but showed no resistance to pyroxsulam, imazethapyr, flucarbazone, and bispyribac-sodium. Notably, those overexpressing CYP704A177 showed resistance to pyroxsulam and bispyribac-sodium, but not to mesosulfuron-methyl, imazethapyr, and flucarbazone. These results indicated that B. syzigachne and transgenic Arabidopsis displayed different cross-resistance patterns to ALS-inhibiting herbicides. Subcellular localization revealed that CYP99A44 and CYP704A177 protein were located in the endoplasmic reticulum. Furthermore, these results clearly indicated that CYP99A44-mediated mesosulfuron-methyl resistance in B. syzigachne and CYP704A177 may be involved in B. syzigachne cross-resistance to pyroxsulam and bispyribac-sodium.


Assuntos
Acetolactato Sintase , Arabidopsis , Herbicidas , Acetolactato Sintase/genética , Herbicidas/farmacologia , Resistência a Herbicidas/genética , Arabidopsis/genética , Poaceae/genética , Sistema Enzimático do Citocromo P-450/genética
7.
Int J Mol Sci ; 23(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36293282

RESUMO

Transmembrane glycoprotein integrins play crucial roles in biochemical processes, and by their inhibition or activation, different signal pathways can be disrupted, leading to abnormal physiological functions. We have previously demonstrated the inhibitory effect of glyphosate herbicide's active ingredient on cell adhesion and its αvß3 integrin antagonist effect. Therefore, it appeared particularly exciting to investigate inhibition of glyphosate and its metabolites on a wider range of Arg-Gly-Asp (RGD) binding integrins, namely αvß3, α5ß1 and αllbß3. Thus, the purpose of this study was to assess how extended the inhibitory effect observed for glyphosate on the integrin αvß3 is in terms of other RGD integrins and other structurally or metabolically related derivatives of glyphosate. Five different experimental setups using enzyme-linked immunosorbent assays were applied: (i) αvß3 binding to a synthetic polymer containing RGD; (ii) αvß3 binding to its extracellular matrix (ECM) protein, vitronectin; (iii) α5ß1 binding to the above polymer containing RGD; (iv) αllbß3 binding to its ECM protein, fibrinogen and (v) αvß3 binding to the SARS-CoV-2 spike protein receptor binding domain. Total inhibition of αvß3 binding to RGD was detected for glyphosate and its main metabolite, aminomethylphosphonic acid (AMPA), as well as for acetylglycine on α5ß1 binding to RGD.


Assuntos
COVID-19 , Herbicidas , Humanos , Integrina alfaVbeta3/metabolismo , Vitronectina , Herbicidas/farmacologia , SARS-CoV-2 , Oligopeptídeos/química , Ensaio de Imunoadsorção Enzimática , Fibrinogênio , Polímeros
8.
Int J Mol Sci ; 23(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36232394

RESUMO

To find novel herbicidal compounds with high activity and broad spectrum, a series of phenylpyridine moiety-containing α-trifluoroanisole derivatives were designed, synthesized, and identified via nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). Greenhouse-based herbicidal activity assays revealed that compound 7a exhibited > 80% inhibitory activity against Abutilon theophrasti, Amaranthus retroflexus, Eclipta prostrate, Digitaria sanguinalis, and Setaria viridis at a dose of 37.5 g a.i./hm2, which was better than fomesafen. Compound 7a further exhibited excellent herbicidal activity against Abutilon theophrasti and Amaranthus retroflexus in this greenhouse setting, with respective median effective dose (ED50) values of 13.32 and 5.48 g a.i./hm2, both of which were slightly superior to fomesafen (ED50 = 36.39, 10.09 g a.i./hm2). The respective half-maximal inhibitory concentration (IC50) for compound 7a and fomesafen when used to inhibit the Nicotiana tabacum protoporphyrinogen oxidase (NtPPO) enzyme, were 9.4 and 110.5 nM. The docking result of compound 7a indicated that the introduction of 3-chloro-5-trifluoromethylpyridine and the trifluoromethoxy group was beneficial to the formation of stable interactions between these compounds and NtPPO. This work demonstrated that compound 7a could be further optimized as a PPO herbicide candidate to control various weeds.


Assuntos
Amaranthus , Herbicidas , Benzamidas/farmacologia , Herbicidas/química , Herbicidas/farmacologia , Plantas Daninhas , Protoporfirinogênio Oxidase/química , Relação Estrutura-Atividade , Tabaco
9.
Int J Mol Sci ; 23(19)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36232781

RESUMO

Weed interference in the crop field is one of the major biotic stresses causing dramatic crop yield losses, and the development of herbicide-resistant crops is critical for weed control in the application of herbicide technologies. To identify herbicide-resistant germplasms, we screened 854 maize inbreed lines and 25,620 seedlings by spraying them with 1 g/L glufosinate. One plant (L336R), possibly derived from a natural variation of line L336, was identified to have the potential for glufosinate tolerance. Genetic analysis validated that the glufosinate tolerance of L336R is conferred by a single locus, which was tentatively designated as ZmGHT1. By constructing a bi-parental population derived from L336R, and a glufosinate sensitive line L312, ZmGHT1 was mapped between molecular markers M9 and M10. Interestingly, genomic comparation between the two sequenced reference genomes showed that large scale structural variations (SVs) occurred within the mapped region, resulting in 2.16 Mb in the inbreed line B73, and 11.5 kb in CML277, respectively. During the fine mapping process, we did not detect any additional recombinant, even by using more than 9500 F2 and F3 plants, suspecting that SVs should also have occurred between L336R and L312 in this region, which inhibited recombination. By evaluating the expression of the genes within the mapped interval and using functional annotation, we predict that the gene Zm00001eb361930, encoding an aminotransferase, is the most likely causative gene. After glufosinate treatment, lower levels of ammonia content and a higher activity of glutamine synthetase (GS) in L336R were detected compared with those of L336 and L312, suggesting that the target gene may participate in ammonia elimination involving GS activity. Collectively, our study can provide a material resource for maize herbicide resistant breeding, with the potential to reveal a new mechanism for herbicide resistance.


Assuntos
Herbicidas , Aminobutiratos , Amônia/metabolismo , Glutamato-Amônia Ligase/metabolismo , Resistência a Herbicidas/genética , Herbicidas/metabolismo , Herbicidas/farmacologia , Melhoramento Vegetal , Transaminases/metabolismo , Zea mays/genética , Zea mays/metabolismo
10.
Harmful Algae ; 118: 102311, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36195425

RESUMO

Numerous products and techniques are used to combat harmful cyanobacterial blooms in lakes. In this study, we tested nine products, the phosphate binders Phoslock® and Aqual-PTM, the coagulant chitosan, the phosphorus binder and coagulant aluminum salts (aluminum sulphate and sodium aluminate), the copper-based algicides SeClear, Captain® XTR and CuSO4·5H2O, the antibiotic Streptomycin and the oxidant hydrogen peroxide (H2O2) on their efficiency to manage the cyanobacterium Microcystis aeruginosa (M. aeruginosa). To this end, 7 days of laboratory experiments were conducted and effects were determined on chlorophyll-a, photosystem II efficiency (PSII), soluble reactive phosphorus (SRP) and intracellular and extracellular microcystin (MC) concentrations. The algicides, chitosan and H2O2 were the most powerful in reducing cyanobacteria biomass. Biomass reductions compared to the controls yielded: Chitosan (99.8%) > Hydrogen peroxide (99.6%) > Captain XTR (98.2%) > SeClear (98.1%) > CuSO4·5H2O (97.8%) > Streptomycin (86.6%) > Phoslock® (42.6%) > Aqual-PTM (28.4%) > alum (5.5%). Compounds that caused the largest reductions in biomass also strongly lowered photosystem II efficiency, while the other compounds (Phoslock®, Aqual-PTM, aluminum salts) had no effect on PSII, but strongly reduced SRP. Intracellular MC concentration followed the biomass patterns, extracellular MC was generally lower at higher doses of algicides, chitosan and H2O2 after one week. Recovery of PSII was observed in most algicides and chitosan, but not at the highest doses of SeClear and in all streptomycin treatments. Our results revealed that M. aeruginosa can be killed rapidly using several compounds, that in some treatments already signs of recovery occurred within one week. P fixatives are efficient in reducing SRP, and thus acting via resource suppression, which potentially may provide an addition to fast-acting algicides that kill most of the cells, but allow rapid regrowth as sufficient nutrients remain.


Assuntos
Quitosana , Cianobactérias , Herbicidas , Microcystis , Alumínio/farmacologia , Antibacterianos/farmacologia , Quitosana/farmacologia , Clorofila , Cobre/farmacologia , Fixadores/farmacologia , Herbicidas/farmacologia , Peróxido de Hidrogênio , Microcistinas/farmacologia , Oxidantes/farmacologia , Fosfatos , Fósforo/farmacologia , Complexo de Proteína do Fotossistema II , Sais/farmacologia , Estreptomicina/farmacologia , Sulfatos/farmacologia
11.
J Phys Chem B ; 126(41): 8140-8154, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36205931

RESUMO

Antibiotic resistance is a major global health concern. The increased use of herbicides may lead to multiple antibiotic resistance in bacteria. Conventional techniques for diagnosing antibiotic resistance are laborious, time-intensive, expensive, and lack information about antibiotic susceptibility. On the other hand, Raman spectroscopy is a rapid, label-free, noninvasive alternative to traditional techniques to detect antibiotic resistance. In this study, two popular herbicides 2,4-dichlorophenoxy acetic acid (2,4-D) and N-(phosphonomethyl)glycine (glyphosate) were used to study their effects on the emergence of antibiotic resistance. The Escherichia coli wild-type (WT) MG1655 strain and two isogenic mutants, Δlon and ΔacrB, were used together with Raman spectroscopy. The WT E. coli is sensitive to antibiotics, but exposure to both herbicides induces antibiotic resistance. Using an excitation wavelength of 785 nm, the intensity ratios (e.g., I740/I785, I740/I1003, I1480/I1445, I2934/I2868, and I2934/I2845) were identified as biomarkers to study the induction of antibiotic resistance in bacteria but not NaCl-mediated stress. Using an excitation wavelength of 633 nm, the peak intensity at 740 cm-1 assigned to cytochrome bd decreases under antibiotic stress but increases upon exposure to both herbicides and antibiotics, indicating the development of resistance. Thus, this study can be applied to monitor antibiotic resistance using Raman spectroscopy.


Assuntos
Escherichia coli , Herbicidas , Herbicidas/farmacologia , Análise Espectral Raman , Ácido Acético , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Ácido 2,4-Diclorofenoxiacético/farmacologia , Citocromos
12.
PLoS One ; 17(10): e0274945, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36201477

RESUMO

The occurrence of freezing stress around herbicides application is one of the most important factors influencing their performance. This experiment was performed to evaluate the efficacy of clodinafop-propargyl and 2,4-D plus MCPA (2,4-Dichlorophenoxyacetic acid plus 2-methyl-4-chlorophenoxyacetic acid), the most important herbicides used in wheat fields in Iran, under the influence of a freezing treatment (-4°C). Wheat and its two common weeds, winter wild oat (Avena ludoviciana Durieu) and turnipweed [Rapistrum rugosum (L.) All.], were exposed to the freezing treatment for three nights from 7:00 P.M. to 5:00 A.M. before and after herbicide application, and their response was compared with plants that did not grow under freezing stress. Under no freezing (NF) and freezing after spray (FAS) conditions, winter wild oat was completely controlled with the recommended dose of clodinafop-propargyl (64 g ai ha-1; hereafter g ha-1). However, the survival percentage of winter wild oat in the freezing before spray (FBS) of clodinafop-propargyl 64 g ha-1 was 7%, and it was completely controlled with twice the recommended dose (128 g ha-1). Under NF conditions and FAS treatment, turnipweed was completely controlled with twice the recommended dose of 2,4-D plus MCPA (2025 g ae ha-1; hereafter g ha-1), while there was no complete control under recommended rate. However, in the FBS treatment, the survival of turnipweed was 7% under double dose. The LD50 (dose required to control 50% of individuals in the population) and GR50 (dose causing 50% growth reduction of plants) rankings were NF

Assuntos
Ácido 2-Metil-4-clorofenoxiacético , Brassicaceae , Herbicidas , Ácido 2,4-Diclorofenoxiacético/farmacologia , Avena , Herbicidas/farmacologia , Humanos , Plantas Daninhas , Propionatos , Piridinas , Triticum
13.
Sci Rep ; 12(1): 17273, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36241676

RESUMO

Arthropod declines have been linked to agricultural intensification. However, information about the impacts of intensification is still limited for many crops, as is our understanding of the responses of different arthropod taxa and trophic groups, thus hindering the development of effective mitigation measures. We investigated the impacts of olive farming intensification on canopy-dwelling arthropods in the Mediterranean region. Intensification involves the increased use of agrochemicals, mechanisation and irrigation, but also structural changes from traditional orchards with low densities of large and old trees, to intensive and superintensive orchards with high to very high densities of smaller and younger trees, respectively. Canopy arthropods were vacuum-sampled at 53 sites representing the three orchard intensification levels, in spring, summer and autumn 2017. We evaluated how the arthropod community varied across intensification levels, and in response to orchard structure, management and landscape context. We found no changes in the diversity of arthropod taxa across intensification levels after correcting for sample coverage, but arthropod abundance declined markedly along the intensification gradient. Decreased abundance was associated with changes in orchard structure, lower herbaceous cover, and higher herbicide and insecticide use. The abundance of a specialized olive pest was lower in landscapes with higher woodland cover. The negative effects of intensification were stronger in spring and summer than in autumn, and parasitoids and predators were particularly affected. Overall, results suggest that retaining herbaceous cover, reducing agrochemical inputs and preserving natural woody elements in the landscape, may contribute to mitigate impacts of olive farming intensification on canopy arthropods, particularly on beneficial species.


Assuntos
Artrópodes , Herbicidas , Inseticidas , Olea , Agricultura/métodos , Animais , Artrópodes/fisiologia , Ecossistema , Florestas , Herbicidas/farmacologia , Inseticidas/farmacologia
14.
Int J Mol Sci ; 23(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36233154

RESUMO

Many plants naturally synthesize and secrete secondary metabolites that exert an allelopathic effect, offering compelling alternatives to chemical herbicides. These natural herbicides are highly important for sustainable agricultural practices. Ailanthone is the chemical responsible for the herbicidal effect of Ailanthus altissima, or "tree of heaven". The molecular studies involving ailanthone's effect on plant growth are limited. In the current study, we combined whole-transcriptome and physiology analysis of three Arabidopsis thaliana ecotypes treated with ailanthone to identify the effect of this allelopathic chemical on genes and plant growth. Our physiology results showed 50% reduced root growth, high proline accumulation, and high reactive-oxygen-species accumulation in response to ailanthone stress. Deep transcriptome analysis revealed 528, 473, and 482 statistically significant differentially expressed genes for Col-0, Cvi-0, and U112-3 under ailanthone stress, including 131 genes shared among the three accessions. The common genes included 82 upregulated and 42 downregulated genes and varied in expression at least twofold. The study also revealed that 34 of the 131 genes had a similar expression pattern when Arabidopsis seedlings were subjected to other herbicides. Differentially expressed genes significantly induced in response to ailanthone included DTXL1, DTX1, ABCC3, NDB4, UGT74E2, and AZI1. Pathways of stress, development and hormone metabolism were significantly altered under ailanthone stress. These results suggest that ailanthone triggers a significant stress response in multiple pathways similar to other herbicides.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Herbicidas , Transportadores de Cassetes de Ligação de ATP/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Herbicidas/metabolismo , Herbicidas/farmacologia , Hormônios/metabolismo , Oxigênio/metabolismo , Prolina/metabolismo , Quassinas , Estresse Fisiológico/genética , Transcriptoma
15.
Pest Manag Sci ; 78(11): 4939-4946, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36181421

RESUMO

BACKGROUND: Chenopodium album L. is a troublesome weed in spring-planted crops, and different levels of ploidy have been documented for this weed species. A population of C. album has evolved resistance to dicamba. The level of ploidy and inheritance of dicamba resistance was studied in this population. RESULTS: The resistant and susceptible individuals of C. album were confirmed as tetraploid by flow cytometry. Pair-crosses were made between ten resistant and susceptible individuals. Eight F1 individuals from five crosses were confirmed resistant after treating with dicamba at 400 g a.e. ha-1 . These individuals were selfed, and the response of their progenies to dicamba was assessed in dose-response experiments, and the results confirmed the resistance trait was dominant. Furthermore, an analysis of the segregation patterns revealed that the segregation response of all F2 progenies fitted a 3:1 (resistant/susceptible) ratio when treated with dicamba at 200, 400 and 800 g a.e. ha-1 , suggesting a single gene was responsible for dicamba resistance. CONCLUSIONS: Dicamba resistance in the studied tetraploid population of C. album is governed by a single dominant gene. This type of inheritance suggests that selection for dicamba resistance can occur readily. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Chenopodium album , Herbicidas , Chenopodium album/genética , Dicamba , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Humanos , Tetraploidia
16.
Pest Manag Sci ; 78(12): 5313-5324, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36054636

RESUMO

BACKGROUND: Chlorsulfuron, metsulfuron-methyl and ethametsulfuron can damage sensitive crops in rotation pattern as a result of their long persistence in soil. To explore novel sulfonylurea (SU) herbicides with favorable soil degradation rates, four series of SUs were synthesized through a structure-based drug design (SBDD) strategy. RESULTS: The target compounds, especially Ia, Id and Ie, exhibited prospective herbicidal activity against dicotyledon oil seed rape (Brassica campestris), amaranth (Amaranthus retroflexus), monocotyledon barnyard grass (Echinochloa crusgalli) and crab grass (Digitaria sanguinalis) at a concentration of 15 a.i. g ha-1 . Additionally, Ia, Id and Ig displayed excellent inhibitory effects against AtAHAS, with Kapp i values of 59.1, 34.5 and 71.8 µm, respectively, which were much lower than that of chlorsulfuron at 149.4 µm. The π-π stack and H-bonds between the Ia conformation and AtAHAS in the molecular docking results confirmed the series of compounds to be conventional AHAS inhibitors. In alkaline soil (pH = 8.46), compounds Ia-Ig revealed various degrees of acceleration in the degradation rate compared with chlorsulfuron. Besides, compound Ia showed considerable wheat and corn safety under postemergence at the concentration of 30, 60 and even 120 a.i. g ha-1 . CONCLUSION: Overall, based on the synthetic procedure, herbicidal activity, soil degradation and crop safety, the Ia sulfonylureas series were chosen to be investigated as prospective AHAS inhibitors. The 5-dimethylamino group on SUs accelerated the degradation rate at different levels in alkaline soils which seems to be controllable in conventional cropping systems in their further application. © 2022 Society of Chemical Industry.


Assuntos
Echinochloa , Herbicidas , Herbicidas/farmacologia , Solo , Simulação de Acoplamento Molecular , Estudos Prospectivos , Relação Estrutura-Atividade , Compostos de Sulfonilureia/farmacologia , Digitaria
18.
Sci Rep ; 12(1): 15241, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36085300

RESUMO

Hood canarygrass (Phalaris paradoxa L.) is a problematic weed in winter crops of Australia. Experiments were conducted to determine the effects of environmental factors on seed germination of P. paradoxa and wheat (Triticum aestivum L.) and herbicide options for P. paradoxa control. Results revealed that P. paradoxa had higher germination (> 89%) at a temperature range from 15/5 ℃ to 25/15 ℃ [day/night (12 h/12 h] compared with 30/20 ℃ and 35/25 ℃. At a temperature regime of 30/20 ℃, P. paradoxa had 1% germination; however, wheat at this temperature range resulted in 79% germination. Exposure of seeds of P. paradoxa to > 150 ℃ pretreatment (radiant heat for 5 min) resulted in no germination. These results suggest that infestation of P. paradoxa could be reduced by residue burning or by planting wheat crops early in the season when the temperature is relatively high. At a water potential of -0.8 MPa, seed germination of P. paradoxa and wheat was 75 and 96%, respectively. Similarly, at the highest salt concentration (200 mM sodium chloride), seed germination of P. paradoxa and wheat was 73 and 79%, respectively. These observations suggest that like wheat, P. paradoxa is also highly tolerant to water and salt stress conditions, therefore, it could invade the agro-ecosystem under water and salt stress situations. Germination of P. paradoxa was found to be low (10%) on the soil surface, suggesting that no-till systems could inhibit the germination of P. paradoxa. Pre-emergent (PRE) herbicides, namely cinmethylin, pyroxasulfone, and trifluralin, provided 100% control of P. paradoxa; however, in the presence of 2 t ha-1 of residue cover, pyroxasulfone provided better control of P. paradoxa compared with other herbicides. Post-emergent (POST) herbicides clethodim, haloxyfop, and paraquat provided excellent control of P. paradoxa, even if the plant size was large (10-leaf stage). Knowledge generated from this study will help in strengthening the integrated management of P. paradoxa.


Assuntos
Herbicidas , Phalaris , Produtos Agrícolas , Ecossistema , Germinação , Herbicidas/farmacologia , Sementes , Triticum , Água
19.
J Agric Food Chem ; 70(36): 11429-11440, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36048004

RESUMO

Aegilops tauschii Coss. is a malignant weed in wheat fields in China, its herbicide resistance has been threatening crop production. This study identified one mesosulfuron-methyl-resistant(R) population, JJMHN2018-05 (R), without target resistance mutations. To fully understand the resistance mechanism, non-target site resistance was investigated by using transcriptome sequencing combined with a reference genome. Results showed that the cytochrome P450 monooxygenase (P450) inhibitor malathion significantly increased the mesosulfuron-methyl sensitivity in R plants, and greater herbicide-induced glutathione S-transferase (GST) activity was also confirmed. Liquid chromatography with tandem mass spectrometry analysis further supported the enhanced mesosulfuron-methyl metabolism in R plants. Gene expression data analysis and qRT-PCR validation indicated that eight P450s, six GSTs, two glycosyltransferases (GTs), four peroxidases, and one aldo-keto reductase (AKRs) stably upregulated in R plants. This research demonstrates that the P450s and GSTs involved in enhanced mesosulfuron-methyl metabolism contribute to mesosulfuron-methyl resistance in A. tauschii and identifies potential contributors from metabolic enzyme families.


Assuntos
Aegilops , Herbicidas , Aegilops/genética , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Compostos de Sulfonilureia/farmacologia , Transcriptoma
20.
Plant Physiol Biochem ; 189: 126-138, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36084528

RESUMO

Glyphosate residues retained in the growing meristematic tissues or in grains of glyphosate-resistant crops affect the plants physiological functions and crop yield. Removing glyphosate residues in the plants is desirable with no penalty on crop yield and quality. We report a new combination of scientific strategy to detoxify glyphosate that reduces the residual levels and improve crop resistance. The glyphosate detoxifying enzymes Aldo-keto reductase (AKR1) and mutated glycine oxidase (mGO) with different modes of action were co-expressed with modified EPSPS, which is insensitive to glyphosate in tobacco (Nicotiana tabacum L.) and rice (Oryza sativa L.). The transgenic tobacco plants expressing individual PsAKR1, mGO, CP4-EPSPS, combinations of PsAKR1:CP4EPSPS, PsAKR1:mGO, and multigene with PsAKR1: mGO: CP4EPSPS genes were developed. The bio-efficacy studies of in-vitro leaf regeneration on different concentrations of glyphosate, seedling bioassay, and spray on transgenic tobacco plants demonstrate that glyphosate detoxification with enhanced resistance. Comparative analysis of the transgenic tobacco plants reveals that double and multigene expressing transgenics had reduced accumulation of shikimic acid, glyphosate, and its primary residue AMPA, and increased levels of sarcosine were observed in all PsAKR1 expressing transgenics. The multigene expressing rice transgenics showed improved glyphosate resistance with yield maintenance. In summary, results suggest that stacking genes with two different detoxification mechanisms and insensitive EPSPS is a potential approach for developing glyphosate-resistant plants with less residual content.


Assuntos
Herbicidas , Oryza , 3-Fosfoshikimato 1-Carboxiviniltransferase/genética , Aldo-Ceto Redutases , Glicina/análogos & derivados , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Óxido de Magnésio , Plantas Geneticamente Modificadas , Sarcosina/genética , Ácido Chiquímico , Tabaco/genética , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
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