Spray application factors and plant growth regulator performance: II. Foliar uptake of gibberellic acid and 2, 4-D

Experiments were initiated during 2003 and 2004 to evaluate application placement equipment for plant growth regulator (PGR) applications along bahiagrass roadsides. Recently designed equipment combine low-volume application and pesticide placement technology. Application placement equipment conceal the image of a traditional spray application. Evaluated application placement equipment included a wet-blade mower (Burch Wet Blade) and rotary-wick applicator (Weedbug™) compared with a traditional broadcast spray. Wet-blade mowers are designed to mow and simultaneously apply a pesticide solution to a cut stem or leaf in a single pass, whereas rotary-wick applicators are designed to wick a solution onto foliage. Evaluated PGRs included imazapic (9, 35, or 53 g ha−1) and sulfometuron-methyl (26 g ha−1). Bahiagrass injury varied with application placement equipment and was greater with rotary-wick applications in 2003, compared with foliar broadcast applications and the wet-blade mower. Bahiagrass seedhead suppression ranged from 31 to 60% with application placement equipment in July 2003 compared with 93% for a broadcast spray. In 2004, rotary wick- or broadcast-applied PGRs provided excellent (> 90%) seedhead suppression. Although application placement equipment may have advantages to broadcast-spray applications, evaluated equipment did not enhance bahiagrass suppression along roadsides in North Carolina compared with a foliar broadcast spray. Additional research is needed to determine if this type of application may provide consistent results with other species and compounds.

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Plant Growth Regulator Impacts on Vegetative Cutting Production of Moroccan Pincushion (Pterocephalus depressus) Plants

Journal of Environmental Horticulture ◽

10.24266/0738-2898-39.2.62 ◽

2021 ◽

Vol 39 (2) ◽

pp. 62-67

Author(s):

Sean J. Markovic ◽

James E. Klett

Keyword(s):

Plant Growth ◽

Gibberellic Acid ◽

Plant Growth Regulators ◽

Growth Regulators ◽

Growth Regulator ◽

Plant Growth Regulator ◽

Growth Index ◽

Dry Weight ◽

Stock Plant ◽

Cutting Production

Abstract Moroccan pincushion (Pterocephalus depressus) is a drought-tolerant perennial that is being used in landscapes throughout arid areas of the western United States. This paper describes two experiments researching vegetative cutting production from stock plants. Moroccan pincushion stock plants received foliar applications of gibberellic acid (GA3), benzyladenine, ethephon, or auxin [indole-3-butyric acid (IBA)] plant growth regulators (PGR). Plant growth regulators were applied singularly and in combination with GA3 to determine efficacy on stock plant growth. A propagation study was conducted simultaneously to determine effects of these different PGR treatments applied to stock plants on the rooting of moroccan pincushion cuttings. The stock plant study showed GA3 + benzyladenine application increased cutting production over other PGR treatments. Fresh weight of moroccan pincushion cuttings did not differ among treatments. While cuttings did not differ in dry weight in experiment 1, statistical differences were observed in experiment 2. However, these differences in dry weight did not affect the quality of the cuttings. Cuttings from stock plants treated with GA3 + IBA treatment had the highest numerical growth index [(height + width + width)/3]. Cuttings from stock plants treated with GA3 alone or in combination with another PGR were all greater in average growth index and statistically differed from those without GA3 being applied. PGR treatments did not affect rooting percentages of the cuttings with nontreated stock plant cuttings successfully rooting at an average rate of 95%. However, GA3 + IBA was the only treatment where cuttings had 100% rooting for both experiments, indicating potential rooting benefits. Index words: Plant growth regulator, propagation, Pterocephalus depressus, vegetative cuttings. Species used in this study: Moroccan pincushion [Pterocephalus depressus Archibald]. Chemicals used in this study: gibberellic acid (GA3), benzyladenine, ethephon, indole-3-butyric acid (IBA).

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Effects of Gibberellic Acid Treatments on Fruit and Seed Development of Muscadine Grapes

HortScience ◽

10.21273/hortsci.31.4.662f ◽

1996 ◽

Vol 31 (4) ◽

pp. 662f-663

Author(s):

J. Lu ◽

O. Lamikanra

Keyword(s):

Plant Growth ◽

Gibberellic Acid ◽

Growth Regulator ◽

Plant Growth Regulator ◽

Maximal Increase ◽

Genotype Variation ◽

Before And After ◽

Early Ripening ◽

Grape Cultivars ◽

Muscadine Grapes

Gibberellic acid, a plant growth regulator commonly sprayed for seedless bunch grape cultivars, was used to spray on the seeded muscadine grape cultivars `Carlos', `Fry', `Higgins' and `Triumph'. GA3 at 100 to 300 ppm were sprayed on leaves and fruit clusters before and after anthesis. The flower/fruit clusters also were dipped into a much higher concentration (1000 ppm) in addition to the sprayed concentration of GA3. Berry weight significantly increased in all the sprayed vines, with a maximal increase up to 50%. Early and more uniform ripening was observed in the cultivar `Triumph'. More than 20% of seedless berries also were found on the GA3-sprayed `Triumph' vines. However, the latter two responses (early ripening and seedlessness) did not occur in other cultivars tested. Similar results also were obtained in the dipping treatments. The results indicated that the seeded muscadine grapes responded well to the GA3 treatments in general, but genotype variation is obvious.

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Optimization of Gibberellic Acid Production in Endophytic Bacillus cereus Using Response Surface Methodology and Its Use as Plant Growth Regulator in Chickpea

Journal of Plant Growth Regulation ◽

10.1007/s00344-021-10492-2 ◽

2021 ◽

Author(s):

Nitin Baliyan ◽

Sandhya Dhiman ◽

Shrivardhan Dheeman ◽

Sandeep Kumar ◽

Naveen Kumar Arora ◽

...

Keyword(s):

Response Surface Methodology ◽

Plant Growth ◽

Gibberellic Acid ◽

Bacillus Cereus ◽

Response Surface ◽

Growth Regulator ◽

Plant Growth Regulator ◽

Acid Production

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Spray application factors and plant growth regulator performance: III. Interaction of daminozide uptake, translocation and phytotoxicity in bean seedlings

Pest Management Science ◽

10.1002/(sici)1526-4998(200001)56:1<43::aid-ps86>3.0.co;2-j ◽

2000 ◽

Vol 56 (1) ◽

pp. 43-48 ◽

Cited By ~ 2

Author(s):

Moritz Knoche ◽

Martin J Bukovac

Keyword(s):

Plant Growth ◽

Growth Regulator ◽

Plant Growth Regulator ◽

Spray Application

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Manipulating Primocane Architecture in Thornless Blackberry with Uniconazole, GA3, and BA

HortScience ◽

10.21273/hortsci.27.2.116 ◽

1992 ◽

Vol 27 (2) ◽

pp. 116-118 ◽

Cited By ~ 1

Author(s):

Hermen Malik ◽

Douglas D. Archbold

Keyword(s):

Plant Growth ◽

Gibberellic Acid ◽

Growth Regulator ◽

Plant Growth Regulator ◽

Branch Length ◽

Dry Weight ◽

Thornless Blackberry

The potential for plant growth regulator (PGR) manipulation of `Chester Thornless' blackberry (fibus spp.) primocane growth was evaluated. PGR treatments included combinations of soil-applied uniconazole at 1, 5, 25, and 125 mg/plant and GA, foliar-applied one or two times at 100 ppm 3 and 4 weeks after a 25-mg/plant uniconazole application. Also, GA and BA were applied at 100 ppm alone or in combination one, two, or three times. Increasing rates of uniconazole reduced primocane length, leaflet count, and leaf, cane, and root dry weights. GA, applications reduced primocane length and increased branch elongation but failed to reverse the effects of uniconazole at 25 mg/plant, except those on branch length, leaflet count, and primocane dry weight. Only applications of BA + GA, increased both branch production and elongation and dry weights of some component tissues, while BA alone generally had no effects. Chemical names used: (E)-1-(p-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-1-penten-3-ol (uniconazole); N-(phenylmethyl)-1H-purin-6-amine (benzyladenine, BA); gibberellic acid (GA).

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