scholarly journals Growth Retardants Affect Growth and Flowering of Scaevola

HortScience ◽  
2000 ◽  
Vol 35 (1) ◽  
pp. 36-38 ◽  
Author(s):  
Terri W. Starman ◽  
Millie S. Williams

The effects of concentration and method of application of uniconazole on growth and flowering of Scaevola aemula R. Br. `New Wonder', `Mini Pink Fan', `Purple Fan', and `Royal Fan', Scaevola albida (Sm.) Druce. `White Fan', and Scaevola striata `Colonial Fan' were studied, as was the efficacy of four other growth retardants on S. aemula `New Wonder'. Variables measured included plant width, flower stem number, flower stem length, flower number per stem, flower number per cm stem length, and days to flower. Uniconazole (1.0 mg·L–1) applied as a medium drench to S. aemula `New Wonder' reduced plant width and flower stem length without affecting flower stem number or time to flower. Flower number per stem and number of flowers per cm of stem length were increased, resulting in attractive, compact clusters of flowers. Paclobutrazol medium drench at 4.0 mg·L–1 gave similar results. Daminozide and ethephon sprays reduced plant width; however, flower number was reduced and ethephon delayed flowering. Ancymidol did not affect the parameters measured. When uniconazole drenches were applied to the other cultivars, plant width and flower stem length in all cultivars except `White Fan' decreased as rate increased. Spray applications reduced plant width of all cultivars except `Mini Pink Fan'. Flower stem length was not affected in any cultivar. Flowering habit was improved more in S. aemula `New Wonder', `Purple Fan', and `Royal Fan' than in the other cultivars. Chemical names used: α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol (ancymidol); butanedioic acid mono (2,2-dimethylhydrazide) (daminozide); (2-chloroethyl)phosphonic acid (ethephon); β-[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol); (E)-(s)-1-(4-chlorophenyl)-4,4-dimethy-2-(1,2,4-triazol-1-yl)-pent-1-ene-3-ol (uniconazole).

2003 ◽  
Vol 13 (2) ◽  
pp. 293-296 ◽  
Author(s):  
Ryan M. Warner ◽  
John E. Erwin

One-time spray applications [about 6 mL (0.2 fl oz)] of chlormequat chloride [1000 or 2000 mg·L-1 (ppm)], daminozide (2500 or 5000 mg·L-1), paclobutrazol (20 or 40 mg·L-1) and uniconazole (5 or 10 mg·L-1) varied in efficacy in reducing Hibiscus coccineus (Medic.) Walt., H. radiatus Cav., and H. trionum L. (flower-of-an-hour) stem elongation. Chlormequat chloride inhibited stem elongation of all species, with a 2000 mg·L-1 application reducing stem length of H. coccineus, H. radiatus, and H. trionum by 87%, 42%, and 52%, respectively, compared to untreated plants, 28 d after application. Paclobutrazol also inhibited stem elongation of all species. Uniconazole reduced stem elongation of H. coccineus and H. radiatus, but not H. trionum. Daminozide applied at 5000 mg·L-1 reduced H. radiatus stem elongation only. Growth retardants examined in this study did not delay flowering of H. trionum, the only species that flowered during the experiment. (Chemical names used: ancymidol (α-cyclopropyl-α-(4-methoxyphenol)-5-pyrimidinemethonol), chlormequat chloride(2-chloroethyltrimethylammonium chloride), paclobutrazol ((+)-(R*,R*)-beta((4-chlorophenyl)methyl)-alpha-(1,1-dimethyl)-1H-1,2,4-triazol-1-ethanol), daminozide ([butanedioic acid mono(2,2-dimethylhydrazide)], uniconazol-P ((E)-(+)-(s)-1-(4-chlorophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)pent-1-ene-3-ol)).


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 522b-522
Author(s):  
Terri Woods Starman ◽  
Millie S. Williams

Fan flower (Scaevola aemula L.) has become a popular specialty bedding and hanging basket plant in the United States. The genus contains several species from Australia and the Indo-Pacific region and there exists a wide diversity of growth habits and flower colors, including blue, violet, pink and white. Our objective was to measure the effect of type of growth retardant, method of application, and chemical concentration on S. aemula `New Wonder', `Mini Pink Fan', 'Purple Fan', and `Royal Fan', S. albida 'White Fan', and S. striata `Colonial Fan'. Variables measured included days to flower, plant width, flower stem number, flower stem length, and flower number per stem. Uniconazole applied as a media drench to S. aemula `New Wonder' at 1.0 and 2.0 mg·L–1 decreased plant width and flower stem length without affecting time to flower or flower number. Therefore, number of flowers per cm of stem length on S. aemula `New Wonder' was increased, resulting in attractive, compact clusters of flowers on pendulus stems. Paclobutrazol drench (4.0 and 8.0 mg·L–1) was also effective. Daminozide spray (5000 mg·L–1) reduced plant width but flower number was reduced. Ancymidol foliar sprays and media drenches (all rates) had no effect on the parameters measured. Ethephon (500 and 1000 mg·L–1) reduced plant width, but delayed flowering and reduced flower number. Uniconazole drenches were beneficial in improving the quality of S. aemula. `New Wonder' grown in hanging baskets, but the growth control was not long-lived. The effect of uniconzole on plant growth varied with Scaevola species and cultivars.


HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 466B-466
Author(s):  
Meriam Karlsson

Eight-week-old plants of Anemone coronaria L. `Mona Lisa Series' were transplanted into 10-cm pots and placed in growth chambers at 12, 16, or 20°C and 8, 12 or 16 hr of day length. The irradiance was 12 mol/day per m2. Following the exposure to treatment conditions for 8 weeks, the plants developed in a greenhouse at 16°C and 16 hr of 10-12 mol/day per m2. The fastest appearance of flower buds and flowering were observed for plants grown at 16 hr of day length and 16°C (77 ± 5.4 days from transplant, 133 days from seeding). However, the rate of development was not significantly different from the plants at 12°C and 12 hr of day length (81 ± 3.6 days). Flowering at 20°C required significantly more time at an average 93 ± 9.9 days from transplant. Leaf number at flowering increased with temperature from 9 1.5 leaves at 12°C to 12 ± 3.4 leaves at 16°C and 15 ± 3.4 leaves at 20°C. Flower stem length was significantly longer for plants grown at 12°C or 16 hr of day length (32 ± 0.5 cm) than plants grown at any of the other conditions (26 ± 0.5 cm). The average flower size (length of the petals) was 3.8 ± 0.6 cm for all plants in the study.


2013 ◽  
Vol 53 (2) ◽  
pp. 77-83
Author(s):  
Anna Pobudkiewicz ◽  
Joanna Nowak ◽  
Małgorzata Podwyszyńska ◽  
Andrzej Przybyła

The experiment was conducted to inhibit the growth of dwarf alstroemeria cultivars 'Rosalina' and 'Dorotea' using flurprimidol and daminozide. Additionally, the effect of these retardants on days to anthesis, flowering shoots number, diameter and longevity of florets was evaluated. In vitro propagated plants, grown in 12 cm pots were treated with single sprays of flurprimidol (7,5, 15, 22,5 mg l<sup>-1</sup>) and daminozide (2500, 3500, 4500 mg 1<sup>-1</sup>) following second pruning, when shoots were 9-12 cm long. Well retarded plants of both dwarf alstroemeria cultivars were obtained when plants were sprayed with flurprimidol at 22.5 mg 1<sup>-1</sup>. Plants treated with daminozide at all tested concentrations were to tall to be grown in 12 cm pots. Flurprimidol significantly reduced the canopy diameter, number of flowering shoots of alstroemeria cultivars 'Rosalina' and 'Dorotea' and floret size of cultivar 'Rosalina'. Daminozide had no effect on the number of days to flower but flurprimidol delayed flowering of tested cultivars only at concentration of22.5 mg 1<sup>-1</sup>. Intensified green leaf colour was observed on flurprimidol treated plants. The chemical names used: a-(1-methylethyl)-a-[4-(trifluoromethyloxy)-phenyl]-5-pyrimidine-methanol (flurprimidol), butanedioic acid mono (2,2-dimethylhydrazide) (daminozide).


2010 ◽  
Vol 20 (1) ◽  
pp. 220-223 ◽  
Author(s):  
Timothy W. Miller ◽  
Carl R. Libbey

Mid-summer, foliar-applied paraquat is often used to control weeds and desiccate foliage of field-grown narcissus (Narcissus pseudonarcissus) prior to bed reshaping in the autumn. Paraquat-treated narcissus plants sometimes display chlorotic foliage the subsequent growing season. A trial was conducted to determine if paraquat causes that injury and if so, under what conditions paraquat may be safely applied to narcissus. Narcissus (‘Flower Carpet’ hybrid) was treated with two rates of paraquat at three summer application timings and was then evaluated for damage to new foliar growth the following spring. Flower number and flower stem length was also measured and bulb yield was determined. Narcissus foliage displayed 50% to 77% chlorosis in February after half-green foliage was treated with paraquat at 0.47 or 0.78 lb/acre, respectively, the previous summer. Foliage was still 13% to 63% chlorotic, respectively, at flowering. Paraquat at both rates applied to half-green foliage also reduced flower number and flower stem length in one of two iterations, as well as reducing average bulb weight 18% to 33%. If applied when leaves were 75% dry, foliar damage and reduction in average bulb weight was limited to the 0.78 lb/acre rate, while flower number and stem length were not affected at either rate. When desiccating late-season narcissus foliage and weeds with paraquat, therefore, growers are advised to delay application until narcissus foliage is about 75% dry and most of the flower stems have fallen, and to use a maximum of 0.47 lb/acre.


Author(s):  
Vladimír Gryc ◽  
Petr Horáček

The paper was aimed at the determination of variability of horizontal resin canal dimension in spruce wood in relation to the position in a spruce stem. Significant changes of dimensions in horizontal resin canal along the stem length and radius were found. On the basis obtained of results 3D models (for CW, OW, SWL and SWP zones) describing changes in resin canal dimensions in spruce in relation to the position in a stem were created. In the models, the resin canal dimension decreases with the height of a stem and on the other hand, with an increasing distance from the stem pith the dimension of resin canal increases. The importance of the paper consists in the enlargement of findings about the structure of spruce with compression wood.


2018 ◽  
Vol 24 (3) ◽  
pp. 255-260
Author(s):  
Carlos Eduardo Ferreira de Castro ◽  
Ana Cecilia Ribeiro Castro ◽  
Charleston Gonçalves ◽  
Vivian Loges

Many species of Zingiber have great ornamental potential, due to durability and exotic appearance of the inflorescences. Despite its large phenotypic variability, they are scarcely exploited or not yet exploited regarding the ornamental potential. To conserve potential ornamental genotypes, and subsidize breeding program, the Agronomic Institute (IAC) maintain a Germoplasm Collection of Ornamental Zingiberales with promising accessions, including Zingiber. The aim was the morphophenological characterization of ten Zingiber accessions and the indication for landscape purposes. A large variation was observed to the evaluated characters: Clump height (CH); Inflorescence visualization (IV); Clump area (CA); Clump density (CD); Leaf stem Firmness (LSF); Number of leaf stems per clump (NLSC); Number of leaves per stem (NLS); Leaf color (LCol); Evergreen tendency (ET); Flower stem growth (FSG); Flower stem length (FSLe); Flower stem diameter (FSD); Flower stem per clump (FSC); Color sensorial perception (CSP); Flower stem weight (FSW); Inflorescence length (IL); Inflorescence diameter (ID); Bracts aspects (BAs); and Flowering season (FSe). The accessions very suitable and with the best performance to use for landscape purpose were Z. spectabile, IAC Anchieta (Z. spectabile), Z. newmanii.


1990 ◽  
Vol 70 (3) ◽  
pp. 925-930 ◽  
Author(s):  
PETER R. HICKLENTON

This study investigated the effects of growth retardants uniconazole [(E) - (p-chlorohenyl) -4, 4-dimethyl-2-(1,2,4-triazol-1-yl)-1-penten-3-ol] and daminozide (butanedioic acid mono 2,2-dimethylhydrazide) on three chrysanthemum (Dendranthema grandiflora Tzvelev.) cultivars. Uniconazole applied as a soil drench (0.02 mg a.i. pot−1) or foliar spray (0.014 mg a.i. pot−1) 10 d after removal of the shoot tip reduced plant height at harvest in cultivars Deep Luv, Tip and Tara. Higher doses of uniconazole resulted in further plant height reduction in Tip and Tara but not in Deep Luv. Daminozide spray (14 mg a.i. pot) and uniconazole spray (0.028 or 0.056 mg a.i. pot−1) produced plants of similar height. Pre-plant dips of both growth retardants were less effective than sprays or drenches in controlling height. Flower area and flower dry weight were reduced with uniconazole drench and spray, and daminozide spray in each cultivar. Shoot dry weight was similarly affected in Tip and Tara but not in Deep Luv. Flowering was delayed in each cultivar by post-plant treatments of uniconazole drench and spray and by daminozide spray (0.08, 0.014 and 14 mg a.i. pot−1, respectively), and by daminozide and uniconazole pre-plant dips (5.0 mg L−1 and 4000 mg L−1, respectively).Key words: Sumagic, XE-1019, B-Nine, Alar, Chrysanthemum × morifolium, Dendanthema grandiflora


2006 ◽  
Vol 84 (7) ◽  
pp. 1101-1109 ◽  
Author(s):  
Leonid V. Kurepin ◽  
Lisa Mancell ◽  
David M. Reid ◽  
Richard P. Pharis ◽  
C.C. Chinnappa

Four phenotypically different genotypes from an alpine population of Stellaria longipes Goldie s.l. (Caryophyllaceae) were collected from neighbouring sites at the top of the Plateau Mountain in southeastern Alberta, Canada, to examine a possible hormonal basis for their differences in stem length, leaf size, and flowering characteristics. All four genotypes had a dwarf shoot phenotype, compared with the low-elevation ecotype. Among the four genotypes, PMI-D was the tallest and had the largest leaves and flowers as well as more flowers per plant. PMI-D also maintained the flowering state, upon repropagation, without low temperature, short-day vernalization. Under controlled long-day warm conditions, the PMI-D genotype had a higher rate of ethylene evolution, but contained levels of endogenous gibberellin A1 that were similar to the other three (smaller) alpine genotypes. PMI-D was more sensitive to exogenously applied ethylene and growth-active gibberellins than other alpine genotypes. In contrast, the other three genotypes were smaller, had fewer (and smaller) flowers, and exhibited low ethylene evolution and a reduced sensitivity to applied ethylene and growth-active gibberellins. Speculatively, this behaviour may indicate an adaptation within this unique population of “dwarf” phenotypes that involves enhanced sensitivity to endogenous ethylene and gibberellins.


1992 ◽  
Vol 10 (2) ◽  
pp. 87-90
Author(s):  
James T. Foley ◽  
Gary J. Keever

Abstract Pink polka-dot plant, Hypoestes phyllostachya Bak., was treated with one or two foliar spray applications of Bonzi (paclobutrazol) (25, 50, or 100 ppm), Cycocel (chlormequat chloride) (3500 ppm) or B-Nine (daminozide) (3500 ppm) to suppress shoot elongation. One or two applications of 3500 ppm Cycocel (chlormequat chloride) retarded shoot elongation, resulting in consistently mounded plants. Bonzi (paclobutrazol) and B-Nine (daminozide) also suppressed shoot elongation but to a lesser degree, and plants were not uniform.


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