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1.
J Agric Food Chem ; 67(36): 10010-10017, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31414816

RESUMO

Dominican farmers have started to apply synthetic auxin herbicides (SAHs) as the main alternative to mitigate the impacts of the occurrence of glyphosate-resistant (GR) Parthenium hysterophorus populations in citrus orchards. A GR P. hysterophorus population survived field labeled rates of glyphosate, 2,4-dichlorophenoxyacetic acid (2,4-D), dicamba, and picloram, which showed poor control (<50%). In in vivo assays, resistance levels were high for glyphosate and moderate for picloram, dicamba, and 2,4-D. Sequencing the 5-enolpyruvylshikimate-3-phosphate synthase gene revealed the double Thr-102-Ile and Pro-106-Ser amino acid substitution, conferring resistance to glyphosate. Additionally, reduced absorption and impaired translocation contributed to this resistance. Regarding SAH, impaired 2,4-D transport and enhanced metabolism were confirmed in resistant plants. The application of malathion improved the efficacy of SAHs (control >50%), showing that metabolism of these herbicides was mediated by cytochrome P450 enzymes. This study reports, for the first time, multiple resistance to SAHs and glyphosate in P. hysterophorus.


Assuntos
Asteraceae/efeitos dos fármacos , Citrus/crescimento & desenvolvimento , Glicina/análogos & derivados , Resistência a Herbicidas , Herbicidas/farmacologia , Ácidos Indolacéticos/farmacologia , Ácido 2,4-Diclorofenoxiacético/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Asteraceae/metabolismo , Dicamba/metabolismo , Dicamba/farmacologia , Glicina/metabolismo , Glicina/farmacologia , Herbicidas/metabolismo , Ácidos Indolacéticos/metabolismo
3.
C R Biol ; 342(5-6): 220-229, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31400945

RESUMO

The in vitro cultivation of date palm staminodes (vestigial stamens) at different stages of female floral ontogenesis confirms the persistence at an immature state of such organs at all the floral differentiation stages. This is evidenced even in fully mature female flowers. Our study revealed the advanced developmental patterns of these rudimentary structures, which bear diverse morphogenetic potentialities. In vitro cultivation of staminodes provides new opportunities for in vitro regeneration of date palm. Such developmental processes were found to be modulated by the stage of floral differentiation, which closely reflected the level of staminode maturity. Development was also impacted by the composition and concentration in plant growth regulators (NAA, BAP and 2,4-D) of the culture media. The large morphogenetic plasticity of the staminodes disposed them to evolutionary variations of the date palm reproduction system. The practical benefits (micropropagation) and the fundamental interests (evolutionary process) of our investigation are discussed.


Assuntos
Evolução Biológica , Phoeniceae/fisiologia , Ácido 2,4-Diclorofenoxiacético/farmacologia , Compostos de Benzil/farmacologia , Meios de Cultura , Flores/crescimento & desenvolvimento , Flores/fisiologia , Herbicidas/farmacologia , Morfogênese , Ácidos Naftalenoacéticos/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Purinas/farmacologia
4.
Biomed Res Int ; 2019: 3698742, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31111050

RESUMO

Rauwolfia tetraphylla L. is an important medicinal plant species which is well known for its pharmaceutically important alkaloids. In the present study, we are reporting about its conservation by in vitro clonal multiplication through the standardized protocol of indirect regeneration by using leaf and stem based callus and assessment of genetic fidelity of acclimated plantlets by start codon targeted (SCoT), inter simple sequence repeats (ISSR), and randomly amplified polymorphic DNA (RAPD) marker based analysis. Initially friable callus was induced in maximum amounts (378.7, 323.8, and 412.8 in mg) from leaf, root, and stem explants on Murashige and Skoog (MS) media supplemented with 5.0 mg/L, 3.0 mg/L of 2,4-dichlorophenoxyacetic acid (2,4-D) and 5.0 mg/L of naphthalene acetic acid (NAA), respectively. Shoot regeneration with the maximum number of shoot buds (25 and 20) was obtained from leaf and stem calluses on MS media supplemented with TDZ (0.25 mg/L) + BAP (2 mg/L). The regenerated shoots were rooted successfully with maximum rooting percentage of 98.0 on full strength MS media amended with IAA (1.0 mg/L) and IBA (1.0 mg/L). The regenerated plantlets were hardened using 2:1 ratio of sterile garden soil and sand, followed by acclimatization in field conditions with 86% of survival. SCoT, ISSR, and RAPD primers based polymerase chain reaction (PCR) analysis was carried out to check possible genetic variations in micro propagated plants in comparison with mother plant. Among the ten SCoT (S), ISSR (R), and RAPD (OPA) primers used, S2, R10, and OPA3 has given good amplification with scorable DNA bands. The results revealed that the regenerated plants did not have any polymorphism with mother plant. Hence, the in vitro regenerated R. tetraphylla plantlets were confirmed as true-to-type.


Assuntos
Aclimatação/efeitos dos fármacos , Códon de Iniciação , Repetições de Microssatélites , Plantas Medicinais/crescimento & desenvolvimento , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos , Rauwolfia/crescimento & desenvolvimento , Regeneração/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/farmacologia , Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Primers do DNA , DNA de Plantas/genética , Marcadores Genéticos , Variação Genética , Ácidos Indolacéticos/farmacologia , Cinetina/farmacologia , Compostos de Fenilureia/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Caules de Planta/efeitos dos fármacos , Caules de Planta/crescimento & desenvolvimento , Plantas Medicinais/efeitos dos fármacos , Plantas Medicinais/genética , Rauwolfia/efeitos dos fármacos , Rauwolfia/genética , Regeneração/genética , Tiadiazóis/farmacologia
5.
Pest Manag Sci ; 75(11): 2925-2933, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30843341

RESUMO

BACKGROUND: Amaranthus palmeri S. Wats is among the most problematic annual broadleaf weed species in the USA, including in Kansas. In late summer 2015, seeds of an A. palmeri population (MHR) that had survived field-use rates of 2,4-D were collected from Barton County, KS, USA. The main objectives were to: (i) confirm and characterize 2,4-D resistance in a MHR population; (ii) characterize the resistance profile of the MHR population in relation to a multiple herbicide-susceptible (MHS) population to glyphosate, chlorsulfuron, atrazine, mesotrione, fomesafen; and (iii) determine the effectiveness of alternative POST burndown herbicides for controlling MHR population. RESULTS: The MHR population had 3.2-fold resistance to 2,4-D. In addition, the MHR population also exhibited multiple resistance to glyphosate (11.8-fold), chlorsulfuron (5.0-fold), atrazine (14.4-fold), and mesotrione (13.4-fold). Furthermore, the MHR population also showed reduced sensitivity to fomesafen (2.3-fold). In a separate study, dicamba with glyphosate, atrazine or fluroxypyr + 2,4-D, and paraquat alone or with atrazine, metribuzin, saflufenacil or 2,4-D provided ≥ 99% injury to the MHR population. Similarly, saflufenacil alone or with atrazine, metribuzin or 2,4-D, and glufosinate alone or with glyphosate + 2,4-D, and glyphosate + dicamba, and a premix of bicyclopyrone + atrazine + mesotrione + S-metolachlor also effectively controlled the MHR population. CONCLUSION: This research confirms the first global case of an A. palmeri population from Kansas with multiple resistance to 2,4-D, glyphosate, chlorsulfuron, atrazine and mesotrione, and reduced sensitivity to fomesafen. Dicamba, glufosinate, paraquat, and saflufenacil alone or in tank-mixtures with PRE herbicides effectively controlled this MHR population. © 2019 Society of Chemical Industry.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Amaranthus/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Resistência a Herbicidas , Amaranthus/fisiologia , Kansas , Controle de Plantas Daninhas
6.
Int J Mol Sci ; 20(5)2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30841619

RESUMO

The auxin-like compound 2,4-dichlorophenoxyacetic acid (2,4-D) has been widely used as a plant growth regulator in cucumber fruit production; however, its influence on fruit development and metabolism has not been evaluated. In this study, the phenotype of cucumber fruits in both 2,4-D treatment and non-treatment control groups were recorded, and the metabolome of different segments of cucumber fruit at various sampling time points were profiled by a standardized non-targeted metabolomics method based on UPLC-qTOF-MS. The application of 2,4-D increased the early growth rate of the fruit length but had no significant effect on the final fruit length, and produced cucumber fruits with fresh flowers at the top. The 2,4-D treatment also affected the cucumber fruit metabolome, causing significant changes in the stylar end at 4 days after flowering (DAF). The significantly changed metabolites were mainly involved in methionine metabolism, the citric acid cycle and flavonoid metabolism pathways. At the harvest stage, 2,4⁻D treatment significantly decreased the levels of flavonoids and cinnamic acid derivatives while increased the levels of some of the amino acids. In summary, exogenous application of 2,4-D can greatly alter the phenotype and metabolism of cucumber fruit. These findings will assist in exploring the mechanisms of how 2,4-D treatment changes the fruit phenotype and evaluating the influence of 2,4-D treatment on the nutritional qualities of cucumber fruit.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Cucumis sativus/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/metabolismo , Frutas/efeitos dos fármacos , Metaboloma/efeitos dos fármacos
7.
Plant Physiol ; 180(1): 480-496, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30737267

RESUMO

Many signal perception mechanisms are connected to Ca2+-based second messenger signaling to modulate specific cellular responses. The well-characterized plant hormone auxin elicits a very rapid Ca2+ signal. However, the cellular targets of auxin-induced Ca2+ are largely unknown. Here, we screened a biologically annotated chemical library for inhibitors of auxin-induced Ca2+ entry in plant cell suspensions to better understand the molecular mechanism of auxin-induced Ca2+ and to explore the physiological relevance of Ca2+ in auxin signal transduction. Using this approach, we defined a set of diverse, small molecules that interfere with auxin-induced Ca2+ entry. Based on annotated biological activities of the hit molecules, we found that auxin-induced Ca2+ signaling is, among others, highly sensitive to disruption of membrane proton gradients and the mammalian Ca2+ channel inhibitor bepridil. Whereas protonophores nonselectively inhibited auxin-induced and osmotic stress-induced Ca2+ signals, bepridil specifically inhibited auxin-induced Ca2+ We found evidence that bepridil severely alters vacuolar morphology and antagonized auxin-induced vacuolar remodeling. Further exploration of this plant-tailored collection of inhibitors will lead to a better understanding of auxin-induced Ca2+ entry and its relevance for auxin responses.


Assuntos
Arabidopsis/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Tabaco/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/farmacologia , Arabidopsis/genética , Proteínas de Bactérias/genética , Bepridil/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Sinalização do Cálcio/fisiologia , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Fenamatos/farmacologia , Ácidos Indolacéticos/antagonistas & inibidores , Medições Luminescentes , Proteínas Luminescentes/genética , Niclosamida/farmacologia , Células Vegetais/efeitos dos fármacos , Células Vegetais/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Plantas Geneticamente Modificadas , Tabaco/genética , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo
8.
Drug Metab Pharmacokinet ; 34(1): 95-103, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30583944

RESUMO

Using X. laevis oocyte expression system, we investigated whether human Na+-coupled monocarboxylate transporter 1 (SLC5A8, hSMCT1) is involved in 2,4-dichlorophenoxyacetate (2,4-D) uptake by the renal tubular epithelial cells. 2,4-D is a herbicide that causes nephrotoxicity. Heterologous expression of hSMCT1 in X. laevis oocytes conferred the ability to take up 2,4-D; the induced uptake process was Na+-dependent and electrogenic. The Na+-dependent uptake of 2,4-D was inhibited not only by known hSMCT1 substrates, but also by many structural analogs of 2,4-D. The currents induced by 2,4-D, 4-chlorophenoxyacetate (4-CPA) and 2-methyl-4-chlorophenoxyacetate (MCPA) were saturable: the rank order of the maximal induced current and the affinity for hSMCT1was 2,4-D > 4-CPA > MCPA. The relationship between the structures of the derivatives and their transport activity implied specific structural features in a compound for recognition as a substrate by hSMCT1. Furthermore, we have demonstrated using purified rabbit renal brush-border membrane vesicles that 2,4-D potently inhibited the Na+-dependent uptake of pyroglutamate, a typical substrate for Smct1, and that 2,4-D uptake process was Na+-dependent, saturable and inhibitable by a potent blocker, ibuprofen. We conclude that hSMCT1 is involved partially in the renal reabsorption of 2,4-D and its derivatives and their nephrotoxicity.


Assuntos
Ácido 2,4-Diclorofenoxiacético/metabolismo , Herbicidas/metabolismo , Microvilosidades/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Ácido 2,4-Diclorofenoxiacético/química , Ácido 2,4-Diclorofenoxiacético/farmacologia , Animais , Transporte Biológico/fisiologia , Feminino , Herbicidas/química , Herbicidas/farmacologia , Humanos , Microvilosidades/efeitos dos fármacos , Transportadores de Ácidos Monocarboxílicos/química , Coelhos , Xenopus laevis
9.
Physiol Plant ; 166(3): 812-820, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30203555

RESUMO

Parthenocarpy, the productions of seedless fruit without pollination or fertilization, is a potentially desirable trait in many commercially grown fruits, especially in pear, which is self-incompatible. Phytohormones play important roles in fruit set, a process crucial for parthenocarpy. In this study, 2,4-dichlorophenoxyacetic acid (2,4-D), an artificially synthesized plant growth regulator with functions similar to auxin, was found to induce parthenocarpy in pear. Histological observations revealed that 2,4-D promoted cell division and expansion, which increased cortex thickness, but the effect was weakened by paclobutrazol (PAC), a gibberellin (GA) biosynthesis inhibitor. Phenotypic differences in pear may therefore be due to different GA contents. Hormone testing indicated that 2,4-D mainly induced the production of bioactive GA4 , rather than GA3. Three key oxidase genes function in the GA biosynthetic pathway: GA20ox, GA3ox and GA2ox. In a pear group treated with only 2,4-D, PbGA20ox2-like and PbGA3ox-1 were significantly upregulated. When treated with 2,4-D supplemented with PAC, however, expression levels of these genes were significantly downregulated. Additionally, PbGA2ox1-like and PbGA2ox2-like expression levels were significantly downregulated in pear treated with either 2,4-D only or 2,4-D supplemented with PAC. We thus hypothesize that 2,4-D can induce parthenocarpy by enhancing GA4 biosynthesis.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Giberelinas/metabolismo , Pyrus/efeitos dos fármacos , Pyrus/fisiologia , Frutas/efeitos dos fármacos , Frutas/fisiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Triazóis/farmacologia
10.
J Agric Food Chem ; 66(51): 13378-13385, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30516986

RESUMO

Synthetic auxin herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-D), are widely used for selective control of broadleaf weeds in cereals and transgenic crops. Although the troublesome weed wild radish ( Raphanus raphanistrum) has developed resistance to 2,4-D, no populations have yet displayed an enhanced capacity for metabolic detoxification of the herbicide, with both susceptible and resistant wild radish plants readily metabolizing 2,4-D. Using mass spectrometry and nuclear magnetic resonance, the major 2,4-D metabolite was identified as the glucose ester, and its structure was confirmed by synthesis. As expected, both the endogenous and synthetic compounds retained auxin activity in a bioassay. The lack of detectable 2,4-D hydroxylation in wild radish and the lability of the glucose ester suggest that metabolic 2,4-D resistance is unlikely to develop in this species.


Assuntos
Ácido 2,4-Diclorofenoxiacético/química , Ácido 2,4-Diclorofenoxiacético/metabolismo , Herbicidas/química , Herbicidas/metabolismo , Raphanus/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Herbicidas/farmacologia , Espectrometria de Massas , Estrutura Molecular , Raphanus/química , Raphanus/efeitos dos fármacos
11.
Pak J Biol Sci ; 21(8): 376-382, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30417998

RESUMO

BACKGROUND AND OBJECTIVES: Presently, determination of optimum protocol for callus induction of any plant is an important issue in tissue culture technology. Therefore, the main objective of this study was to find out an optimum protocol for callus induction from in vitro cultured jojoba by determining the optimum explant and the best growth regulators mixture for callus induction. MATERIALS AND METHODS: The study used three variant explants namely the leaf disks, seeds and nodal segments for callus formation. Different culture media containing basic Murashige and Skoog (MS) medium components supplemented with various concentrations of 2,4-dichlorophenoxy acetic acid as an auxin (2,4-D) and Kinetin (Kin) as a cytokinin with various concentrations ranging from 0.0, 0.5, 1.0 and 2.0 mg L-1 were used. The total number of treatments were 16. The callus was induced from all explants on MS medium containing the lowest concentration of 2,4-D 0.5 mg L-1 with any concentration of Kin. RESULTS: The results showed that nodal segments were the best for callus formation followed by the leaf disks (leaves) and seeds, respectively. While, the best concentration of proliferation and development of the used explant was 2.00 followed in descending order by 1.00, 0.5 and 0.0 mg L-1, respectively. CONCLUSION: The study find out that the best concentration of 2,4-dichlorophenoxy acetic acid as an auxin (2,4-D) and Kinetin (Kin) as a cytokinin was 2.00 followed in descending order by 1.00, 0.5 and 0.0 mg L-1, respectively for callus induction.


Assuntos
Caryophyllales/química , Extratos Vegetais/farmacologia , Ácido 2,4-Diclorofenoxiacético/farmacologia , Meios de Cultura/farmacologia , Citocininas/farmacologia , Ácidos Indolacéticos/farmacologia , Cinetina/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Folhas de Planta/química , Sementes/química
12.
J Agric Food Chem ; 66(40): 10362-10368, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30230823

RESUMO

Due to high volatility and water solubility, 2,4-dichlorophenoxyacetic acid (2,4-D) can easily enter into the atmosphere and water bodies by volatilization, drift, leaching, or runoff, which results in potential threats to the environment and human health. The physicochemical properties of pesticides can be regulated by preparing their ionic liquids. In this work, a series of dicationic ionic liquids (DILs) of 2,4-D were prepared to reduce its environmental risk and enhance herbicidal activity. The solubility, octanol-water partition coefficient, surface tension, and volatilization rate results of DILs showed that these properties could be optimized by choosing appropriate countercations. Compared to 2,4-D ammonium salt, DILs have lower volatility, water solubility, and surface tension as well as higher lipophilicity. Benefiting from optimized physicochemical properties, DILs HIL8-12 exhibited better herbicidal activity against three typical broadleaf weeds than 2,4-D ammonium salt, and their fresh weight inhibition rates increased by 2.74-46.84%. The safety assessment experiment indicated that DILs were safer to wheat than commercialized forms of 2,4-D. The DILs could reduce the environmental risk of 2,4-D caused by high volatility and water solubility and would be potential alternatives to its commercialized formulations.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Herbicidas/farmacologia , Líquidos Iônicos/farmacologia , Ácido 2,4-Diclorofenoxiacético/química , Herbicidas/química , Líquidos Iônicos/química , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/crescimento & desenvolvimento , Solubilidade , Volatilização
13.
J Plant Physiol ; 229: 158-163, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30096586

RESUMO

2,4-dichlorophenoxyacetic acid (2,4-D) is among the most commonly used herbicides applied for weed control during wheat cultivation. However, its application could affect wheat growth. The present study investigates the effect of the ascomycetous fungus Trichoderma harzianum on lipid peroxidation, phospholipids, signaling lipids and phospholipase D in the seedlings of wheat (Triticum aestivum L.) treated with 2,4-D (2.5 mg L-1). In the group of 4-day-old seedlings exposed to the herbicide, increased lipid peroxidation and inhibition of growth were observed in shoots and roots. Moreover, elevated levels of oxylipins were noted. Among them, the amount of 13-HOTrE oxygenated from linolenic acid (18:3) increased the most significantly. Concurrently, in the seedlings inoculated with T. harzianum, growth was stimulated when the level of phosphatidylcholine (PC) increased. Moreover, in wheat seedlings treated with 2,4-D and T. harzianum, the level of lipid peroxidation was similar to that in the control and there was no increase observed in oxylipins and phospholipase D activity. T. harzianum might have partly alleviated the toxic effect of 2,4-D on wheat seedlings.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Trichoderma/patogenicidade , Triticum/metabolismo , Triticum/microbiologia , Estresse Oxidativo/fisiologia , Fosfatidilcolinas/metabolismo , Fosfolipase D/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Brotos de Planta/microbiologia , Plântula/efeitos dos fármacos , Plântula/metabolismo , Plântula/microbiologia , Triticum/efeitos dos fármacos
14.
J Biochem Mol Toxicol ; 32(9): e22196, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30015991

RESUMO

Glutathione-S-transferases (GSTs) have a function in xenobiotic metabolism. They are a significant multifunctional family with a wide variety of catalytic activities. In the current study, we determined in vitro inhibition effects of 2,4-dichlorophenoxyacetic acid dimethylamine salt (2,4-D DMA), haloxyfop-P-methyl, glyphosate isopropylamine, dichlorvos, and λ-cyhalothrin on purified GST. For this purpose, GST were purified from Van Lake fish (Chalcalburnus tarichii Pallas) liver with 29.25 EU mg-1 specific activity and 10.76% yield using GSH-agarose affinity chromatographic method. The pesticides were tested at various concentrations on in vitro GST activity. Ki constants were calculated as 0.17 ± 0.01, 0.25 ± 0.05, 3.72 ± 0.32, 0.42 ± 0.06, and 0.025 ± 0.004 mM, for 2,4-D DMA, haloxyfop-P-methyl, glyphosate isopropylamine, dichlorvos, and λ-cyhalothrin, respectively. λ-Cyhalothrin showed a better inhibitory effect compared to the other pesticides. The inhibition mechanisms of λ-cyhalothrin were competitive, while the other pesticides were noncompetitive.


Assuntos
Cyprinidae , Inibidores Enzimáticos/toxicidade , Proteínas de Peixes/antagonistas & inibidores , Glutationa Transferase/antagonistas & inibidores , Fígado/enzimologia , Praguicidas/farmacologia , Poluentes Químicos da Água/farmacologia , Ácido 2,4-Diclorofenoxiacético/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Animais , Ligação Competitiva , Cyprinidae/crescimento & desenvolvimento , Diclorvós/metabolismo , Diclorvós/farmacologia , Dimetilaminas/metabolismo , Dimetilaminas/farmacologia , Inibidores Enzimáticos/metabolismo , Proteínas de Peixes/química , Proteínas de Peixes/isolamento & purificação , Proteínas de Peixes/metabolismo , Fungicidas Industriais/metabolismo , Fungicidas Industriais/farmacologia , Glutationa Transferase/química , Glutationa Transferase/isolamento & purificação , Glutationa Transferase/metabolismo , Glicina/análogos & derivados , Glicina/metabolismo , Glicina/farmacologia , Cinética , Lagos , Fígado/crescimento & desenvolvimento , Peso Molecular , Nitrilos/metabolismo , Nitrilos/farmacologia , Praguicidas/metabolismo , Piretrinas/metabolismo , Piretrinas/farmacologia , Piridinas/metabolismo , Piridinas/farmacologia , Águas Salinas , Especificidade da Espécie , Turquia , Poluentes Químicos da Água/metabolismo
15.
Cell Mol Biol (Noisy-le-grand) ; 64(9): 1-5, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30030948

RESUMO

A significant sesquiterpene lactone used as a drug is artemisinin. It is definitely an anti-parasitic drug isolated from field-grown Artemisia annua L. a plant from Asteraceae family. It is the best treatment for Plasmodium falciparum malaria. Unfortunately, artemisinin content in A. annua is extremely low (0.01-0.8% dry weight). So, some researchers focused on enhancing artemisinin content either in tissue/cell culture or the whole plant of A. annua sp. The aims of the current study were the effect of plant growth regulators on callus production and improvement of artemisinin content in cell suspension culture of A. annua, an alternative to the whole plant using abiotic elicitors. For callus induction, an experiment was laid out as a factorial experiment with three factors (explant type, different concentrations of BAP and 2,4-D) based on completely randomized design with three replications. The maximum frequency of callus induction (100%) was found in leaf explant on MS medium with a combination of 2, 4-D (3 mg/l) and BAP (1.5 mg/l). Therefore, the best calli were used for cell suspension culture and the effects of GA3 and ABA as abiotic elicitors were evaluated on the improvement of artemisinin production. The results indicated that both ABA and GA3 increased artemisinin content (2.02 fold and 1.67 fold in comparison to control respectively) in cell suspension culture.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Antimaláricos/metabolismo , Artemisia annua/química , Artemisininas/metabolismo , Compostos de Benzil/farmacologia , Células Vegetais/efeitos dos fármacos , Purinas/farmacologia , Ácido Abscísico/farmacologia , Antimaláricos/análise , Artemisia annua/metabolismo , Artemisininas/análise , Cromatografia Líquida de Alta Pressão , Giberelinas/farmacologia , Células Vegetais/química , Células Vegetais/metabolismo , Folhas de Planta/citologia , Caules de Planta/citologia
16.
Sci Rep ; 8(1): 11347, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30054534

RESUMO

Highly-lignified culms of bamboo show distinctive anatomical and mechanical properties compared with the culms of other grass species. A cell culture system for Phyllostachys nigra has enabled investigating the alterations in cellular states associated with secondary cell wall formation during its proliferation and lignification in woody bamboos. To reveal transcriptional changes related to lignification in bamboo, we analyzed transcriptome in P. nigra cells treated with the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D) and the synthetic cytokinin benzylaminopurine (BA) by RNA-seq analysis. We found that some genes putatively involved in cell wall biogenesis and cell division were up-regulated in response to the 2,4-D treatment, and the induction of lignification by the BA treatment was correlated with up-regulation of genes involved in the shikimate pathway. We also found that genes encoding MYB transcription factors (TFs) show correlated expression patterns with those encoding cinnamyl alcohol dehydrogenase (CAD), suggesting that MYB TFs presumably regulate secondary cell wall formation in the bamboo cells. These findings suggest that cytokinin signaling may regulate lignification in P. nigra cells through coordinated transcriptional regulation and metabolic alterations. Our results have also produced a useful resource for better understanding of secondary cell wall formation in bamboo plants.


Assuntos
Lignina/metabolismo , Poaceae/citologia , Poaceae/genética , Transcrição Genética , Ácido 2,4-Diclorofenoxiacético/farmacologia , Compostos de Benzil/farmacologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Reguladores de Crescimento de Planta/farmacologia , Poaceae/efeitos dos fármacos , Purinas/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Genética/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
17.
PLoS One ; 13(6): e0199677, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29933393

RESUMO

The study reports the response to herbicide of the 2,4-dichlorophenoxyacetic acid (2,4-D)-degrading fungal strain Umbelopsis isabellina. A comparative analysis covered 41 free amino acids as well as 140 lipid species of fatty acids, phospholipids, acylglycerols, sphingolipids, and sterols. 2,4-D presence led to a decrease in fungal catalase activity, associated with a higher amount of thiobarbituric acid-reactive substances (TBARS). Damage to cells treated with the herbicide resulted in increased membrane permeability and decreased membrane fluidity. Detailed lipidomic profiling showed changes in the fatty acids composition such as an increase in the level of linoleic acid (C18:2). Moreover, an increase in the phosphatidylethanolamine/phosphatidylcholine ratio was observed. Analysis of fungal lipid profiles revealed that the presence of 2,4-D was accompanied by the accumulation of triacylglycerols, a decrease in ergosterol content, and a considerable rise in the level of sphingolipid ceramides. In the exponential phase of growth, increased levels of leucine, glycine, serine, asparagine, and hydroxyproline were found. The results obtained in our study confirmed that in the cultures of U. isabellina oxidative stress was caused by 2,4-D. The herbicide itself forced changes not only to membrane lipids but also to neutral lipids and amino acids, as the difference of tested compounds profiles between 2,4-D-containing and control samples was consequently lower as the pesticide degradation progressed. The presented findings may have a significant impact on the basic understanding of 2,4-D biodegradation and may be applied for process optimization on metabolomic and lipidomic levels.


Assuntos
Ácido 2,4-Diclorofenoxiacético , Membrana Celular/metabolismo , Fungos não Classificados/metabolismo , Herbicidas , Lipídeos de Membrana/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ácido 2,4-Diclorofenoxiacético/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacologia , Herbicidas/metabolismo , Herbicidas/farmacologia
18.
Int J Biol Macromol ; 118(Pt A): 427-434, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29944937

RESUMO

The inhibitory effect of 2,4,5-T, 2,4-D, glyphosate and paraquat on the diphenolase activity of mushroom tyrosinase for oxidation of L-DOPA has been investigated by kinetic measurements, fluorescence spectroscopy and computational docking analysis. 2,4,5-T and 2,4-D inhibit the diphenolase activity of the enzyme following a competitive mechanism, while glyphosate is a mixed inhibitor according to Lineweaver-Burk kinetic analysis. The inhibitory activity follows the order glyphosate >2,4,5-T > 2,4-D with IC50 values of 65, 90 and 106 µM, respectively. Intrinsic tyrosinase fluorescence quenching and computational docking analysis suggest that 2,4,5-T and 2,4-D interact with the active site of the enzyme through hydrophobic interactions, while glyphosate also interacts with external residues of the active site of the enzyme by hydrogen bonding and hydrophilic interactions inducing conformational changes in the protein structure.


Assuntos
Catecol Oxidase/química , Monofenol Mono-Oxigenase/química , Praguicidas/farmacologia , Ácido 2,4,5-Triclorofenoxiacético/farmacologia , Ácido 2,4-Diclorofenoxiacético/farmacologia , Agaricales/enzimologia , Domínio Catalítico/efeitos dos fármacos , Catecol Oxidase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Glicina/análogos & derivados , Glicina/farmacologia , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Cinética , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Oxirredução/efeitos dos fármacos , Análise Espectral
19.
Ann Bot ; 122(4): 627-640, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-29893784

RESUMO

Background and Aims: Resistance to synthetic auxin herbicides such as 2,4-dichlorophenoxyacetic acid (2,4-D) is increasing in weed populations worldwide, which is of concern given the recent introduction of synthetic auxin-resistant transgenic crops. Due to the complex mode of action of the auxinic herbicides, the mechanisms of evolved resistance remain largely uncharacterized. The aims of this study were to assess the level of diversity in resistance mechanisms in 11 populations of the problem weed Raphanus raphanistrum, and to use a high-throughput, whole-genome transcriptomic analysis on one resistant and one susceptible population to identify important changes in gene expression in response to 2,4-D. Methods: Levels of 2,4-D and dicamba (3,6-dichloro-2-methoxybenzoic acid) resistance were quantified in a dose-response study and the populations were further screened for auxin selectivity, 2,4-D translocation and metabolism, expression of key 2,4-D-responsive genes and activation of the mitogen-activated proein kinase (MAPK) pathway. Potential links between resistance levels and mechanisms were assessed using correlation analysis. Key Results: The transcriptomic study revealed early deployment of the plant defence response in the 2,4-D-treated resistant population, and there was a corresponding positive relationship between auxinic herbicide resistance and constitutive MAPK phosphorylation across all populations. Populations with shoot-wide translocation of 2,4-D had similar resistance levels to those with restricted translocation, suggesting that reduced translocation may not be as strong a resistance mechanism as originally thought. Differences in auxin selectivity between populations point to the likelihood of different resistance-conferring alterations in auxin signalling and/or perception in the different populations. Conclusions: 2,4-D resistance in wild radish appears to result from subtly different auxin signalling alterations in different populations, supplemented by an enhanced defence response and, in some cases, reduced 2,4-D translocation. This study highlights the dangers of applying knowledge generated from a few populations of a weed species to the species as a whole.


Assuntos
Resistência a Herbicidas , Herbicidas/farmacologia , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Raphanus/fisiologia , Transdução de Sinais , Ácido 2,4-Diclorofenoxiacético/farmacologia , Dicamba/farmacologia , Raphanus/efeitos dos fármacos , Especificidade da Espécie
20.
Chemosphere ; 203: 151-159, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29614408

RESUMO

It is generally assumed that zooplankton can recolonize lakes that have been exposed to pesticides, via their dormant egg banks. Hitherto, few studies have evaluated the relative importance of dormant egg bank recruitment in the re-establishment of zooplankton communities in the presence of pesticide. This study investigated the effects of commercial products Bratt® (a.i. 2,4-D), Roundup® (a.i. glyphosate) and their mixture on the emergence (abundance and taxon richness) of dormant zooplankton egg banks from natural lake sediment. Sediment samples were collected from the surface sediment (<10 cm depth) in four lakes in Southeast São Paulo, Brazil. We performed a hatching experiment, in which natural lake sediments containing dormant eggs were exposed separately to Bratt® (applied concentrations ranging from 0.30 to 20 mg L-1), Roundup® (0.28-8.5 mg L-1), and combined mixtures of all concentrations, plus one control (non-exposure to formulated herbicides) for a period of 28 days. All tested concentrations of Bratt®, Roundup® and their mixture reduced the abundance and taxon richness of emerging zooplankton (except 2 mg L-1 of Bratt®). This effect was more pronounced in rotifers. In comparison, there were no negative effects on the emergence of microcrustaceans. These findings suggest that commercial products Bratt®, Roundup® and their mixture can suppress the emergence of rotifers, thereby influencing zooplankton recruitment potential in lakes impacted by the presence of these commercial herbicides. Our results stress the importance of the need for additional studies to assess the effects of pesticides on dormant egg banks.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Glicina/análogos & derivados , Herbicidas/farmacologia , Lagos/química , Rotíferos/crescimento & desenvolvimento , Zooplâncton/crescimento & desenvolvimento , Animais , Brasil , Glicina/farmacologia , Rotíferos/efeitos dos fármacos , Zooplâncton/efeitos dos fármacos
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