scholarly journals Response of Common Garden Annuals to Sublethal Rates of 2,4-D and Dicamba with or without Glyphosate

2020 ◽  
Vol 30 (3) ◽  
pp. 411-420
Author(s):  
Brian Dintelmann ◽  
David Trinklein ◽  
Kevin Bradley

An experiment was conducted in 2017 and 2018 to determine the sensitivity of common garden annuals to sublethal rates of 2,4-dichlorophenoxyacetic acid (2,4-D) and dicamba with or without glyphosate. Sublethal rates corresponding to 1/10×, 1/100×, and 1/300× of the full labeled rate (1×) of 2,4-D (1.0 lb/acre), 2,4-D plus glyphosate (1.0 lb/acre plus 1.0 lb/acre), dicamba (0.5 lb/acre), and dicamba plus glyphosate (0.5 lb/acre plus 1.0 lb/acre) were applied to ‘Prelude’ wax begonia (Begonia ×semperflorens-cultorum), ‘Wizard’ coleus (Solenostemon scutellarioides), ‘Pinto’ zonal geranium (Pelargonium ×hortorum), ‘Dazzler’ impatiens (Impatiens walleriana), ‘Bonanza’ french marigold (Tagetes patula), ‘Hurrah’ petunia (Petunia hybrida), ‘Titan’ madagascar periwinkle (Catharanthus roseus), and ‘Double Zahara’ zinnia (Zinnia marylandica). Visible injury, plant height, number of flowers, and dry weight were recorded at specific time intervals after treatment. When averaged across all annual plant species, the 1/10× rate of 2,4-D plus glyphosate resulted in 51% injury 28 days after treatment, whereas the 1/10× rate of dicamba plus glyphosate resulted in 43% injury. Treatments causing the greatest injury also resulted in the greatest reduction of dry weight, height, and flower production. Coleus was the most sensitive species in the study; dry weight was reduced by 16% and 18% compared with the nontreated controls from 1/300× rates of 2,4-D plus glyphosate and dicamba plus glyphosate, respectively. French marigold and zonal geranium had greater sensitivity to treatments containing 2,4-D, but coleus and zinnia had greater sensitivity to treatments containing dicamba. Petunia exhibited a high tolerance to 2,4-D or dicamba applied alone (>6% injury) but was highly sensitive when glyphosate was added to 2,4-D and dicamba (<65% injury). The 1/100× and 1/300× rates that are likely to equate to sublethal rates in field settings, resulted in less than 15% injury across all flower species except coleus and petunia.

2009 ◽  
Vol 92 (6) ◽  
pp. 1773-1779 ◽  
Author(s):  
Robin C Boro ◽  
K Vikas Singh ◽  
C Raman Suri

Abstract The generation of specific and sensitive antibodies against small molecules is greatly dependent upon the characteristics of the hapten-protein conjugates. In this study, we report a new fluorescence-based method for the characterization of hapten-protein conjugates. The method is based on an effect promoted by hapten-protein conjugation density upon the fluorescence intensity of the intrinsic tryptophan chromophore molecules of the protein. The proposed methodology is applied to quantify the hapten-protein conjugation density for two different chlorophenoxyacetic acid pesticides, 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4-dichlorophenoxybutyric acid (2,4-DB), coupled to carrier protein. Highly sensitive anti-2,4-D and anti-2,4-DB antibodies were obtained using these well-characterized hapten-protein conjugates. The generated antibodies were used in an immunoassay format demonstrating inhibitory concentration (IC50) values equal to 30 and 7 ng/mL for 2,4-D and 2,4-DB, respectively. Linearity was observed in the concentration range between 0.1500 ng/mL with LODs around 4 and 3 ng/mL for 2,4-D and 2,4-DB, respectively, in standard water samples. The proposed method was successfully applied for the determination of the extent of hapten-protein conjugation to produce specific antibodies for immunoassay development against pesticides.


Author(s):  
Sri Kasmiyati ◽  
Elizabeth Betty Elok Kristiani ◽  
Maria Marina Herawati

Artemisia cina is one of a member of genus Artemisia that has potential as a medicinal plant. However, the levels of Artemisia medicinal bioactive compounds are very low. Polyploidization is an alternative method that can enhance of growth and secondary metabolite productions of plants. The aims of this research were to determine the effect of polyploid induction using colchicine and plant growth regulator toward plant growth, the chlorophyll, kaemferol and quercetin contents of A. cina. Four different A. cina used in this research consisted of two diploid genotypes (TWN and KJT) and two polyploid genotypes (J and M). Induction of mutant polyploid was conducted using colchicine and combination of plant growth regulator benziladenyl (BA) and 2,4-dichlorophenoxyacetic acid (2,4-D). The measured plant growth parameters were dry weight, leaf area, and plant height. The chlorophyll content of leaves was determined spectrophotometrically, and flavonoid content determined using HPLC. The result showed that the polyploid genotype (M) significantly decreased leaf and root growth compared to the KJT and TWN. In A. cina plants, polyploidization using colchicine is more effective in increasing the biomass than using combination plant growth regulator BA and 2,4-D. The flavonoid content of KJT was the lowest, and significantly different compared to the other plants. This study provides new information about the effect of polyploid on growth and flavonoid content in A. cina. This can be  useful information to develop A. cina to become a medicinal plant.


2021 ◽  
Vol 2 (5) ◽  
pp. 71-75
Author(s):  
Hasina Sultana ◽  
Lutfun Nahar ◽  
M. Mofazzal Hossain ◽  
Totan Kumar Ghosh ◽  
Md. Sanaullah Biswas

In vitro regeneration of cucumber is relatively difficult for genetic improvement. In this regard, different concentrations of growth regulators and three types of explants (cotyledon, hypocotyl and leaf disc) were investigated for their efficiency on callus induction potential. Among different explants explored for callus induction with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), leaf disc responded earlier (4.67 days) and showed higher percentage of callus induction (91.50%) with 2 mg/l 2,4-D supplemented Murashige and Skoog (MS) media. The same concentration of 2,4-D resulted in the maximum callus fresh (0.56 g) and dry weight (0.39 g) from leaf disc explant. Then the callus was transferred to untreated, 2.0 mg/l BAP + 0.2 mg/l NAA + 1.0 mg/l Kn, 2.0 mg/l BAP + 1.0 mg/l NAA + 1.0 mg/l Kn and 2.0 mg/l BAP + 1.5 mg/l NAA + 1.0 mg/l Kn fortified MS medium. After transferring the callus of different explants to shoot regeneration media containing different concentrations of 6-benzylaminopurine (BAP), 1-naphthaleneacetic acid (NAA) and Kinetin (Kn), only cotyledon callus started to regenerate shoot. The combination of BAP (2 mg/l) + NAA (0.2 mg/l) + Kn (1 mg/l) showed highest shoot regeneration percentage (67.77%) and the maximum number of shoots (5.12) per explant were recorded in the treatment combination of 2 mg/l BAP + 0.2 mg/l NAA + 1 mg/l Kn. These results provided a basis for the optimization of the callus induction protocol of cucumber for genetic transformation.


HortScience ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 879e-879
Author(s):  
Heather Quinney ◽  
Michael R. Evans

Pepper (Capsicum annuum) and impatiens (Impatiens walleriana) plants were grown in substrates composed of 20% perlite and 20%, 40%, 60% or 80% of a coarse, medium or fine grind of fresh rice hulls with the remainder being Sphagnum peat. Impatiens grown in substrates containing 40% of a coarse, medium or fine and 80% of a fine grind of rice hulls had similar shoot dry weights as those grown in a substrate containing 80% peat. Only impatiens grown in a root substrate containing 40% of the coarse grind of fresh rice hulls had lower root dry weight than those grown in substrates containing 80% peat. Peppers grown in a substrate containing 60% and 80% of a coarse, 60% of a medium or 60% and 80% of a fine grind of fresh rice hulls had similar shoot dry weights as those grown in a substrate containing 80% peat. There were no significant differences in pepper root dry weights among the substrates. Impatiens and pepper plants grown in a substrate containing 80% of the fine grind of fresh rice hulls were similar to those grown in 80% peat, and therefore, the fine grind of fresh rice hulls served as a suitable substitute for Sphagnum peat.


1959 ◽  
Vol 37 (6) ◽  
pp. 1167-1180 ◽  
Author(s):  
R. W. Shuel

Concentrations of 5 × 10−5 M to 5 × 10−4 M of 3-indoleacetic (IAA), α-naphthaleneacetic, or 2,4-dichlorophenoxyacetic acid usually reduced nectar secretion in excised flowers of Antirrhinum majus L. cultured on sugar solutions. The major part of the reduction occurred at relatively low concentrations of the growth regulators. The percentage reduction by IAA remained fairly constant when the sugar concentration of the medium was varied. Although the growth-regulating compounds promoted ovary growth, increased growth did not appear to have been the cause of reduced nectar yields. IAA sometimes increased nectar secretion. The effect of IAA on secretion was modified by 2,3,5-triiodobenzoic acid. Nectar secretion was partially inhibited by iodoacetic acid, sodium arsenate, dinitrophenol, sodium azide, and fluoroacetic acid at concentrations which caused no visible injury to flowers. Two inhibitors of phosphate transfer, dinitrophenol and sodium arsenate, modified the influence of IAA. The data support the hypothesis that nectar secretion is an active process.


2014 ◽  
Vol 63 (3-4) ◽  
pp. 279-286 ◽  
Author(s):  
Romuald Czerpak ◽  
Andrzej Bajguz ◽  
Bożena Białecka ◽  
Lidia E. Wierzchołowska ◽  
Małgorzata M. Wolańska

In this paper the authors present studies on the effect of auxin precursors and chemical analogues on the growth and biochemical composition in <i>Chlorella pyrenoidosa</i> (<i>Chlorophyceae</i>). Among auxin precursors tryptamine exhibited slightly higher stimulative activity in regard to fresh and dry weight, mineral substances, chlorophylls, carotenoids, monosaccharides (aldohexoses) and water-soluble proteins content in <i>Ch. pyrenoidosa</i> cells as compared to anthranilic acid. Among auxin analogues used phenoxyacetic acid and naphthyl-3-acetic acid had the strongest stimulative effect of the above-mentioned parameters. Their activity was significantly higher than that of auxin precursors. The activity of naphthyl-3-sulphonic acid was slightly lower than that of tryptamine, whereas the stimulation by 2,4-dichlorophenoxyacetic acid was similar to that of anthranilic acid. In <i>Ch. pyrenoidosa</i> cells 2,4-dichlorophenoxyacetic acid and naphthyl-3-sulphonic reached their maximum activity at the latest (between the 15th or 16th day) of the culturing, whereas tryptamine, phenylacetic acid, naphthyl-3-acetic acid and indolyl-3-acetic acid - at the earliest (between the 8th or 12th) day.


HortScience ◽  
1995 ◽  
Vol 30 (7) ◽  
pp. 1393-1395 ◽  
Author(s):  
Anita R. Bahe ◽  
Charles H. Peacock

Grass clippings may comprise a minimum of 35% of yard waste. We investigated whether bioavailable herbicide residues in grass clippings used as mulch would be toxic to desirable plants. In each of three experiments, tall fescue (Festuca arundinacea Schreb.) was treated with a mixture of 2,4-D + dicamba + MCPP at 0.5 g total a.i./m2. Clippings were collected at 1-, 5-, 10-, and 15-day postspray intervals. Clippings at gram equivalent weights relative to desired mulching depths were applied to tomato (Lycopersicon esculentum L.), cucumber (Cucumis sativus L.), salvia (Salvia splendens F.), and marigold (Tagetes tenuifolia Cav.) grown in pots. Plant dry-weight comparisons were made at two destructive harvest intervals, from 2 to 5 weeks after mulching. No mulch and nontreated mulch treatments were used as controls. Growth of tomato and marigold was enhanced when nontreated grass mulch was used compared to no mulch, but growth of cucumber and salvia was not enhanced. The bioavailable residues relative to the postspray interval (1 to 15 days) influenced growth of all species. Mulching depth affected growth of all species, except salvia. Herbicide-treated mulch reduced dry weight by ≤80% for cucumber, 73% for tomato, 65% for marigold, and 34% for salvia compared to controls. Herbicide residues apparently increased with mulching depth, resulting in a cumulative effect inhibiting plant growth. Chemical names used: 2,4-dichlorophenoxyacetic acid (2,4-D); 2-(2-methyl-4-chlorophenoxy) propionic acid (MCPP); and 3,6-dichloro-o-anisic acid (dicamba).


Sign in / Sign up

Export Citation Format

Share Document