Long-term culture with 2,4-dichlorophenoxyacetic acid affects embryogenic competence in sugarcane callus via changes in starch, polyamine and protein profiles

A winter gibberellic acid (GA3) spray consistently reduced flower formation, but had a variable effect on the amount of first-grade fruit in the early harvest of `Clausellina' satsuma (Citrus unshiu Marc.), and in the long term these applications had no significant effect on the value of the crop. Auxin applications increased the amount of first grade-early harvested fruit, and increased crop value as compared to hand-thinned trees. No significant differences in yield or fruit grade could be found among the different auxin applications tried, namely an application of 20 mg·L-1 2,4-dichlorophenoxyacetic acid (2,4-D) at flowering, or applications of 25 mg·L-1 naphthaleneacetic acid (NAA), or 50 mg·L-1 2,4-dicholorophenoxypropionic acid (2,4-DP) at the end of fruitlet abscission. Apart from their effect on size, the auxin applications had only a marginal effect on fruit quality.

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Establishment of Fine Suspension Cultures of Triticum tauschii ([Coss.] Schmal.) which remain Embryogenic for Several Years

Australian Journal of Botany ◽

10.1071/bt97109 ◽

1999 ◽

Vol 47 (4) ◽

pp. 611

Author(s):

Shoukat Afshar-Sterle ◽

James F. Kollmorgen ◽

Geoffrey B. Fincher

Keyword(s):

Suspension Cultures ◽

Dichlorophenoxyacetic Acid ◽

D Genome ◽

Triticum Tauschii ◽

Initiation Phase ◽

Genome Donor ◽

Embryogenic Suspension ◽

2,4 Dichlorophenoxyacetic Acid ◽

Term Maintenance

Immature embryos of 10 accessions of Triticum tauschii, the D genome donor of Triticum aestivum, were used to produce embryogenic callus for the initiation of suspension cultures. For the long-term maintenance of embryogenicity of these suspensions, it was necessary to use different media for the initiation, establishment and maintenance phases. The initiation phase required media supplemented with L-proline, L-asparagine and L-glutamine, together with Dicamba at 12 mg L −1 and maltose. In the establishment phase, it was essential to reduce the concentration of Dicamba to 6 mg L −1 for the rapid production of fine suspension cultures. Finally, the long-term maintenance of a capacity for regeneration depended on the inclusion of 1.1 mg L −1 2,4-dichlorophenoxyacetic acid and 30 g L −1 sucrose in the medium. By the use of these procedures, long-term embryogenic fine suspension cultures were established from two accessions, while non-embryogenic fine suspension cultures were produced from five accessions. Over 90% of plants regenerated from fine suspensions of 1-year-old embryogenic cultures were fertile, and embryogenic suspension cultures retained their regeneration capacity for more than 3 years.

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Short-Term Growth Response to Growth Regulators In Roots of Zea Mays

Australian Journal of Biological Sciences ◽

10.1071/bi9680201 ◽

1968 ◽

Vol 21 (2) ◽

pp. 201 ◽

Cited By ~ 4

Author(s):

DE Bottrill ◽

JB Hanson

Keyword(s):

Root Growth ◽

Growth Response ◽

Similar Degree ◽

Dichlorophenoxyacetic Acid ◽

Short Term ◽

Irreversible Inhibition ◽

Wide Range ◽

2,4 Dichlorophenoxyacetic Acid ◽

Indole 3 Acetic Acid

A study was made of the inhibition of root growth in Z. mays by 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,6-trichlorophenoxyacetic acid (2,4,6�T), and indole-3-acetic acid (IAA) over a wide range of concentrations. IAA and 2,4�D caused identical responses whereas the response to 2,4,6-T was different. Application of 2,4.D or IAA at concentrations of 4�5xl0-4M for 5 min resulted in an immediate reversible inhibition of root growth whereas long-term application gave an irreversible inhibition. The same concentration of 2,4,6-T caused a similar degree of inhibition of root growth, but only after an extended treatment, and the roots could then recover from the inhibition in the presence of the chemical.

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Genome plasticity during the acquisition of embryogenic competence

Genome ◽

10.1139/g99-022 ◽

1999 ◽

Vol 42 (6) ◽

pp. 1134-1143 ◽

Cited By ~ 7

Author(s):

Chiara Geri ◽

Alessandra Turrini ◽

Lucia Giorgetti ◽

Elisa Nicoletti ◽

Vittoria Nuti Ronchi

Keyword(s):

Nuclear Dna ◽

Cultured Cells ◽

Morphological Changes ◽

Dichlorophenoxyacetic Acid ◽

Embryogenic Competence ◽

Daucus Carota L ◽

Gene Copies ◽

Slot Blot Analysis ◽

2,4 Dichlorophenoxyacetic Acid

Hypocotyl explants from carrot and other species experience concomitant segregation events and differentiation of homeotic structures during the first 20 days of culture on 2,4-dichlorophenoxyacetic acid (2,4-D). In addition to these cyto-morphological changes, significant amounts of nuclear DNA are lost, the molecular details of which we investigate in this paper. We have developed a slot-blot analysis assay to study the DNA content of a series of carrot samples; besides the leaves, this survey ranged over different culture timepoints: hypocotyls, cell lines, and somatic embryo stages. We carried on to study the relationship between this DNA loss and sequence complexity modulation. Results from probing sequences that correspond to different degrees of complexity, such as medium repetitive and unique sequences as well as sequences belonging to both classes (ribosomal cistrons, ubiquitin, actin, and chalcone synthase), consistently manifested a reduction in DNA levels during the acquisition of embryogenic competence. In some cases, the cultured cells would contain only 10% of the gene copies observed in the reference tissues. Modulation trends also showed that DNA levels of most sequences recover at the torpedo-plantlet stage, which again correlates DNA modulation and the acquisition of embryogenic competence. These results suggest that similar DNA variations may occur in plants in vivo during meiosis, possibly so that meiotic division may be properly completed.Key words: Daucus carota L., DNA reduction, somatic embryogenesis, totipotency, commitment.

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COMPARISON OF PREVENTIVE ACTION OF ANTIOXIDANTS UNDER PROLONGED EXPOSURE TO AMINE SALT OF 2,4-DICHLOROPHENOXYACETIC ACID

Актуальні проблеми сучасної медицини Вісник Української медичної стоматологічної академії ◽

10.31718/2077-1096.20.1.55 ◽

2020 ◽

Vol 20 (1) ◽

pp. 55-58

Author(s):

Y.A. Tarasenko ◽

O.O. Tykhonova ◽

T.F. Deynega ◽

O.A. Volkova

Keyword(s):

Antioxidant Enzymes ◽

Free Radical ◽

Prolonged Exposure ◽

Antioxidant Properties ◽

Natural Antioxidants ◽

Amine Salt ◽

Dichlorophenoxyacetic Acid ◽

2,4 Dichlorophenoxyacetic Acid ◽

Radical Processes

The article describes the study on the effectiveness of remedies possessing antioxidant properties for chemoprevention of the consequences caused by pesticides toxic effects. 2,4-dichlorophenoxyacetic acid derivatives, and namely, amine salt of 2,4-dichlorophenoxyacetic acid are known as one of the most widely distributed compounds in agriculture. The activation of the free radical processes is considered as a universal mechanism of the damage to biological membranes during chronic intoxication by phenoxyacid derivatives. This work is aimed to compare the preventive effect of the synthetic and natural antioxidants under long-term exposure to the 2,4 - dichlorophenoxyacetic acid. The experiment was performed on Wistar male rats, which received synthetic and natural antioxidants against the background of toxicant administration. Long-term effects of the pesticide caused the activation of the processes of free radical lipid peroxidation, reduced antioxidant supply and activity of antioxidant enzymes. The introduction of medicines with antioxidant properties helped to reduce the content of products of free radical processes, to inhibit the drop of body antioxidant supply and to normalize the activity of antioxidant enzymes. According to the experimental data obtained, the complex of natural antioxidants (tocopherol acetate, ascorbic acid and quercetin) has the most pronounced corrective properties. This enables us to recommend them for chemocorrection of pathological changes resulted from prolonged exposure to pesticides.

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Seasonal variability, long-term distribution (2001–2014), and risk assessment of polar organic micropollutants in the Baltic Sea

Environmental Science and Pollution Research ◽

10.1007/s11356-021-13254-5 ◽

2021 ◽

Author(s):

Kathrin Fisch ◽

Berit Brockmeyer ◽

Wolfgang Gerwinski ◽

Detlef E. Schulz-Bull ◽

Norbert Theobald

Keyword(s):

Baltic Sea ◽

Time Trends ◽

Dichlorophenoxyacetic Acid ◽

Phenoxyacetic Acid ◽

The Baltic Sea ◽

Data Set ◽

Long Time ◽

The Baltic ◽

2,4 Dichlorophenoxyacetic Acid

AbstractFrom 2001 to 2014, 13 surveys were conducted in the Baltic Sea, to determine its pollution of 50 micropollutants. The investigations focused mostly on the German western Baltic Sea; in 2008, one survey covered the entire Baltic Sea. Various groups of herbicides (such as triazines, phenoxyacetic acid, phenylurea), perfluoroalkyl substances, pharmaceuticals, and industrial products were analyzed during these surveys. The highest concentrations (median 1 to 4 ng/L) were observed for atrazine, simazine, chloridazone, 2,4-dichlorophenoxyacetic acid, benzotriazole, primidone, and carbamazepine. Most micropollutants exhibited a relatively homogenous spatial distribution, though some herbicides show elevated concentrations in certain regions (e.g., Odra estuary), indicating a riverine input. The data set was analyzed, both for seasonal influences and long-time trends. Some herbicides exhibited higher concentrations during summertime. Both upward- and downward-directed time trends could be identified for some herbicides and perfluorinated compounds. For most of the detected compounds, a low-risk quotient was calculated. Only the occurrence of carbendazim could potentially pose a higher risk to the Baltic Sea.

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