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result(s) for
"Chlorophenoxyacetic acids"
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Plant growth regulators affect biosynthesis and accumulation profile of isoflavone phytoestrogens in high-productive in vitro cultures of Genista tinctoria
The influence of plant growth regulators on biomass growth and the accumulation of medicinally-relevant isoflavone phytoestrogens, derivatives of genistein and daidzein (8 compounds including aglycones, glucosides and glucoside esters) in callus cultures of Genista tinctoria (Fabaceae) was examined. The experiments included 10 auxins [2,4-dichlorophenoxyacetic acid (2,4-D), p-chlorophenoxyacetic acid, indole-3-acetic acid, indole-3-butyric acid, indole-3-propionic acid, 1-naphthaleneacetic acid, β-naphthoxyacetic acid, picloram, 2,3,5-triiodobenzoic acid (TIBA), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)] and 7 cytokinins [6-benzylaminopurine, forchlorfenuron, 1,3-diphenylurea, 2-isopentenyladenine, kinetin (KIN), thidiazuron, zeatin] applied at 0.5 and 5.0 mg l−1, jointly with 5.0 or 0.5 mg l−1 KIN or 2,4-D (for auxins and cytokinins, respectively—36 phytohormone combinations in total). Statistical analysis of the relationships between callus growth [expressed as growth index (Gi)] and the accumulation of isoflavones showed positive correlation in the cytokinin group (rxy values from 0.13 to 0.61) and negative correlation within auxins (rxy values from −0.31 to −0.39). Among the cytokinins tested, the highest isoflavone content (6,436.26 mg/100 g dry weight) and the fastest biomass growth (Gi = 892.46 %) were obtained for 0.5 mg l−1 KIN used jointly with 5.0 mg l−1 2,4-D. In the group of auxins, the combination of 0.5 mg l−1 TIBA and 5.0 mg l−1 KIN provided the fastest culture growth (Gi = 983.07 %) and the isoflavone concentration of 10,474.23 mg/100 g dry weight, which is so far the highest amount of these metabolites achieved in callus cultures of higher plants.
Journal Article
Slow release of a synthetic auxin induces formation of adventitious roots in recalcitrant woody plants
Clonal propagation of plants by induction of adventitious roots (ARs) from stem cuttings is a requisite step in breeding programs. A major barrier exists for propagating valuable plants that naturally have low capacity to form ARs. Due to the central role of auxin in organogenesis, indole-3-butyric acid is often used as part of commercial rooting mixtures, yet many recalcitrant plants do not form ARs in response to this treatment. Here we describe the synthesis and screening of a focused library of synthetic auxin conjugates in
Eucalyptus grandis
cuttings and identify 4-chlorophenoxyacetic acid–
l
-tryptophan-OMe as a competent enhancer of adventitious rooting in a number of recalcitrant woody plants, including apple and argan. Comprehensive metabolic and functional analyses reveal that this activity is engendered by prolonged auxin signaling due to initial fast uptake and slow release and clearance of the free auxin 4-chlorophenoxyacetic acid. This work highlights the utility of a slow-release strategy for bioactive compounds for more effective plant growth regulation.
Adventitious roots are induced in various woody plants, enabling clonal propagation.
Journal Article
Capillary electrophoresis-mass spectrometry for the direct analysis of glyphosate: method development and application to beer beverages and environmental studies
In this study, we developed and validated a CE-TOF-MS method for the quantification of glyphosate (N-(phosphonomethyl)glycine) and its major degradation product aminomethylphosphonic acid (AMPA) in different samples including beer, media from toxicological analysis with Daphnia magna, and sorption experiments. Using a background electrolyte (BGE) of very low pH, where glyphosate is still negatively charged but many matrix components become neutral or protonated, a very high separation selectivity was reached. The presence of inorganic salts in the sample was advantageous with regard to preconcentration via transient isotachophoresis. The advantages of our new method are the following: no derivatization is needed, high separation selectivity and thus matrix tolerance, speed of analysis, limits of detection suitable for many applications in food and environmental science, negligible disturbance by metal chelation. LODs for glyphosate were < 5 μg/L for both aqueous and beer samples, the linear range in aqueous samples was 5–3000 μg/L, for beer samples 10–3000 μg/L. For AMPA, LODs were 3.3 and 30.6 μg/L, and the linear range 10–3000 μg/L and 50–3000 μg/L, for aqueous and beer samples, respectively. Recoveries in beer samples for glyphosate were 94.3–110.7% and for AMPA 80.2–100.4%. We analyzed 12 German and 2 Danish beer samples. Quantification of glyphosate and AMPA was possible using isotopically labeled standards without enrichment, purification, or dilution, only degassing and filtration were required for sample preparation. Finally, we demonstrate the applicability of the method for other strong acids, relevant in food and environmental sciences such as N-acetyl glyphosate, N-acetyl AMPA (present in some glyphosate resistant crop), trifluoroacetic acid, 2-methyl-4-chlorophenoxyacetic acid, glufosinate and its degradation product 3-(methylphosphinico)propionic acid, oxamic acid, and others.
Journal Article
Lignin-based nanoencapsulation for sustainable herbicide delivery: controlled release and bioactivity of 2,4-D and MCPA compared to commercial formulations
Herbicides are the extensively used class of pesticides, which beside the active ingredient, in their formulation accompanying substances such as emulsifiers, surfactants and others is needed. The potential toxicity of these synthetic chemicals could pose serious risks to the human health, nontarget organism and environment. In this work we developed biodegradable lignin nanoparticles (LNPs) as environmentally friendly and controlled release carriers of 2,4-dichlorophenoxyacetic acid 2,4-D and 2-methyl-4-chlorophenoxyacetic acid MCPA. LNPs were synthesized via solvent-free nanoprecipitation, achieving high entrapment efficiencies of 90.7% (2,4-D) and 97.4% (MCPA), confirmed by ultraviolet–visible spectroscopy. In vitro release studies revealed sustained herbicide release in buffer solutions (pH 5.5–7.5), with 68–74% release over 72 h, compared to rapid release from commercial formulations. Bioactivity assays of on
Descurainia sophia
showed that LNP-encapsulated formulation of herbicides reduced weed dry weight by 62.31% and density by 56.09% compared to untreated controls, statistically matching the weed control efficacy of commercial formulations. Field trials further validated these results. LNP-encapsulated 2,4-D + MCPA reduced
Amaranthus blitoides
dry weight by 91.10% and density by 65.09%, while this new formulation decreased
Chenopodium album
dry weight and density by 96.01% and by 66.75%, respectively. Notably, lignin’s inherent biodegradability and non-toxic nature provide a sustainable alternative to conventional synthetic adjuvants, significantly reducing the risks of environmental contamination. Our study highlights the potential of lignin-based nanoencapsulation to preserve weed control efficacy while promoting environmentally friendly and safer herbicide formulations.
Journal Article
Freezing stress affects the efficacy of clodinafop-propargyl and 2,4-D plus MCPA on wild oat (Avena ludoviciana Durieu) and turnipweed Rapistrum rugosum (L.) All. in wheat (Triticum aestivum L.)
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 LD 50 (dose required to control 50% of individuals in the population) and GR 50 (dose causing 50% growth reduction of plants) rankings were NF
Journal Article
2-Methyl-4-chlorophenoxyacetic acid (MCPA) sorption and desorption as a function of biochar properties and pyrolysis temperature
2-Methyl-4-chlorophenoxyacetic acid (MCPA) is a highly mobile herbicide that is frequently detected in global potable water sources. One potential mitigation strategy is the sorption on biochar to limit harm to unidentified targets. However, irreversible sorption could restrict bioefficacy thereby compromising its usefulness as a vital crop herbicide. This research evaluated the effect of pyrolysis temperatures (350, 500 and 800°C) on three feedstocks; poultry manure, rice hulls and wood pellets, particularly to examine effects on the magnitude and reversibility of MCPA sorption. Sorption increased with pyrolysis temperature from 350 to 800°C. Sorption and desorption coefficients were strongly corelated with each other (R 2 = 0.99; P < .05). Poultry manure and rice hulls pyrolyzed at 800°C exhibited irreversible sorption while for wood pellets at 800°C desorption was concentration dependent. At higher concentrations some desorption was observed (36% at 50 ppm) but was reduced at lower concentrations (1–3% at < 5 ppm). Desorption decreased with increasing pyrolysis temperature. Sorption data were analyzed with Langmuir, Freundlich, Dubinin–Radushkevich and Temkin isotherm models. Freundlich isotherms were better predictors of MCPA sorption (R 2 ranging from 0.78 to 0.99). Poultry manure and rice hulls when pyrolyzed at higher temperatures (500 and 800°C) could be used for remediation efforts (such as spills or water filtration), due to the lack of desorption observed. On the other hand, un-pyrolyzed feedstocks or biochars created at 350°C could perform superior for direct field applications to limit indirect losses including runoff and leaching, since these materials also possess the ability to release MCPA subsequently to potentially allow herbicidal action.
Journal Article
Deciphering migraine pain mechanisms through electrophysiological insights of trigeminal ganglion neurons
Migraine is a complex neurological disorder that affects millions of people worldwide. Despite extensive research, the underlying mechanisms that drive migraine pain and related abnormal sensation symptoms, such as hyperalgesia, allodynia, hyperesthesia, and paresthesia, remain poorly understood. One of the proposed mechanisms is cortical spreading depression (CSD), which is believed to be involved in the regulation of trigeminovascular pathways by sensitizing the pain pathway. Another mechanism is serotonin depletion, which is implicated in many neurological disorders and has been shown to exacerbate CSD-evoked pain at the cortical level. However, the effects of CSD and serotonin depletion on trigeminal ganglion neurons, which play a critical role in pain signal transmission, have not been thoroughly studied. In this study, we aimed to investigate the association between CSD and serotonin depletion with peripheral sensitization processes in nociceptive small-to-medium (SM) and large (L) -sized trigeminal ganglion neurons at the electrophysiological level using rat models. We divided the rats into four groups: the control group, the CSD group, the serotonin depletion group, and the CSD/serotonin depletion group. We induced CSD by placing KCl on a burr hole and serotonin depletion by intraperitoneal injection of PCPA (para-chlorophenoxyacetic acid). We then isolated trigeminal ganglion neurons from all groups and classified them according to size. Using patch-clamp recording, we recorded the excitability parameters and action potential (AP) properties of the collected neurons. Our results showed that in SM-sized trigeminal ganglion neurons, the CSD-SM and CSD/serotonin depletion groups had a higher positive resting membrane potential (RMP) than the control-SM group (
p
= 0.001 and
p
= 0.002, respectively, post-hoc Tukey’s test). In addition, the gap between RMP and threshold in the CSD-SM group was significantly narrower than in the control-SM group (
p
= 0.043, post-hoc Tukey’s test). For L-sized neurons, we observed prolongation of the AP rising time, AP falling time, and AP duration in neurons affected by CSD (
p
< 0.05, pairwise comparison test). In conclusion, our study provides new insights into the underlying mechanisms of migraine pain and abnormal somatosensation. CSD and serotonin depletion promote the transmission of pain signals through the peripheral sensitization process of nociceptive small-to-medium-sized trigeminal ganglion neurons, as well as nociceptive and non-nociceptive large-sized trigeminal ganglion neurons.
Journal Article
Alternative splicing occurs in auxin-mediated trade-off between fruit development and quality in tomato
Background
This study assessed the effects of auxin analog, para-chlorophenoxyacetic acid (pCPA), on fruit set and development in Micro-Tom tomato (TOMJPF00001) via phenotypic, biochemical, metabolomic, and transcriptomic analyses.
Results
pCPA treatment significantly (
p
< 0.05) reduced floral abscission, increased fruit set and yield, while impacting fruit morphology, ripening, sugar content, organoleptic properties, and phytohormone profiles. Metabolomic profiling revealed 836 differentially accumulated metabolites (DAMs). Among these, several phenylpropanoid-related DAMs (isoferulic acid, 6-methylcoumarin, naringenin, hesperetin 5-O-glucoside, quercetin, and dihydrokawain) were upregulated in immature green, mature green, and breaker fruits, but downregulated in red ripe fruits following pCPA application. Transcriptome analysis yielded 35,501 differentially expressed genes (DEGs), including 740 novel genes, with growth stage-specific expression patterns observed in phenylpropanoid, carotenoid, and flavonoid biosynthetic pathways. Particularly, pCPA treatment downregulated chitinase (
Soly04g072000.3
) and acidic endochitinase (
Soly05g050130.3
), potentially enhancing fruit firmness through cell wall stabilization. Reduced accumulation of alpha-L-arabinofuranosidase (
Soly10g077080.2
) and a UDP-glucose 6-dehydrogenase family protein (
Soly06g069550.1
) further supported this observation. In red ripe fruits, pCPA decreased organic acids (malic and citric acids), sugars (fructose, glucose and sucrose), soluble solids (TSS/brix), amino acids (aspartic acid, phenylalanine, valine) and nucleotide (uracil, cytosine) levels, correlating with altered sensory attributes. pCPA also influenced lipid biosynthesis in mature green fruits and consistently downregulated sucrose across all developmental stages, suggesting impacts on carbohydrate metabolism. Furthermore, pCPA treatment altered the expression of genes related to carbohydrate metabolism, including beta-amylase (
Soly08g007130.3
), ADP-glucose pyrophosphorylase (
Soly07g056140.3
), and beta-glucosidase (
Soly11g071640.2
). pCPA-induced alterations in fruit development were correspondingly susceptible to alternative splicing patterns.
Conclusions
These findings provide insights into the molecular mechanisms underlying pCPA-induced changes in tomato fruit set and development, offering valuable information for optimizing horticultural breeding practices and strategies.
Journal Article
The Influence of Different Factors on the Metabolism of Capsaicinoids in Pepper (Capsicum annuum L.)
Pepper is a globally cultivated vegetable known for its distinct pungent flavor, which is derived from the presence of capsaicinoids, a class of unique secondary metabolites that accumulate specifically in pepper fruits. Since the accumulation of capsaicinoids is influenced by various factors, it is imperative to comprehend the metabolic regulatory mechanisms governing capsaicinoids production. This review offers a thorough examination of the factors that govern the metabolism of capsaicinoids in pepper fruit, with a specific focus on three primary facets: (1) the impact of genotype and developmental stage on capsaicinoids metabolism, (2) the influence of environmental factors on capsaicinoids metabolism, and (3) exogenous substances like methyl jasmonate, chlorophenoxyacetic acid, gibberellic acid, and salicylic acid regulate capsaicinoid metabolism. The findings of this study are expected to enhance comprehension of capsaicinoids metabolism and aid in the improvement of breeding and cultivation practices for high-quality pepper in the future.
Journal Article
Fruit-set and Early Fruit Growth in Tomato are Associated with Increases in Indoleacetic Acid, Cytokinin, and Bioactive Gibberellin Contents
Fruit-set, defined as the activation of a developmental program which converts the ovary into a developing fruit, depends on the crosstalk among plant hormones. Here we show that in pollinated ovaries fruit-set is associated with an increase in indole-3-acetic acid (IAA) content and high transcript levels of ToFZY, a gene involved in the tryptophan-dependent auxin biosynthesis pathway. In unpollinated ovaries developed parthenocarpically in response to the synthetic auxin chlorophenoxyacetic acid (4-CPA), ToFZY mRNA levels and IAA content slightly increase. The most likely sequence of events after fertilization involves auxin-mediated activation of gibberellin (GA) synthesis. Fertilization events not only strongly increase SlGA20ox1 and SlGA20ox3 message levels but also increase SlGA2ox2, SlGA2ox4, and SlGA2ox5 mRNA levels, suggesting a concerted regulation to modulate the level of bioactive GAs, GA1 and GA3. 4-chlorophenoxyacetic acid was found to mimic the fertilization events in the stimulation of SlGA20ox1 and SlGA20ox3 mRNA levels, which were also enhanced and increased earlier, but in contrast with pollinated ovaries, SlGA2ox2, SlGA2ox4, and SlGA2ox5 mRNA levels were repressed leading to higher levels of bioactive GAs. We have also analyzed the content of abscisic acid (ABA) and its metabolites dihydrophaseic acid, phaseic acid, and ABA-glucosyl ester and the level of cytokinins (CKs) (free bases and their corresponding ribosides and ribotides) in pollinated and auxin-treated tomato fruits. We show that ABA levels decrease whereas the levels of free CKs increase immediately after pollination or auxin treatment.
Journal Article