scholarly journals Response of Herbaceous Perennials to Growth Retardants Applied at Different Developmental Stages when Grown Under Night-Interrupted Lighting Outdoors in the Southern United States

2013 ◽  
Vol 31 (2) ◽  
pp. 101-108
Author(s):  
Gary J. Keever ◽  
J. Raymond Kessler ◽  
James C. Stephenson
Keyword(s):  
United States ◽  
Developmental Stages ◽  
Shoot Elongation ◽  
Southern United States ◽  
Minimal Effect ◽  
Growth Retardants ◽  
Herbaceous Perennials ◽  
Three Stages ◽  
Plant Growth Retardants

A study was conducted in 2004 and 2005 to determine how ‘Early Sunrise’ coreopsis (Coreopsis grandiflora Hogg ex Sweet. ‘Early Sunrise’), ‘Moonbeam’ coreopsis (Coreopsis verticillata L. ‘Moonbeam’) and ‘Goldsturm’ rudbeckia (Rudbeckia fulgida Aiton ‘Goldsturm’) responded to two plant growth retardants applied at three stages of plant development (SOD) when plants were exposed to night-interrupted lighting (NIL) while grown outdoors under nursery conditions in the southern United States. With few exceptions, height of all species was suppressed by 2 weeks after first treatment (WAT) compared to NIL only, regardless of whether 5000 ppm B-Nine or 20 ppm Sumagic was applied at the beginning of a period of rapid shoot elongation (SOD 2) or 2 weeks prior to (SOD 1) or following this stage (SOD 3), and continued throughout the plants’ vegetative phase, although the level of suppression varied with SOD and PGR. Applying either PGR at SOD 2, when rapid shoot elongation first began, was most effective in suppressing vegetative height of ‘Early Sunrise’ coreopsis and ‘Goldsturm’ rudbeckia, whereas vegetative height suppression of ‘Moonbeam’ coreopsis was not affected by SOD when Sumagic was applied, but suppression was greatest when B-Nine was applied at SOD 1, two weeks before rapid shoot elongation began. ‘Early Sunrise’ coreopsis and ‘Goldsturm’ rudbeckia were shortest at first flower when PGRs were applied at SOD 2 and SOD 3, respectively, but plant height of ‘Moonbeam’ coreopsis at first flower was not affected by SOD. Where differences in height suppression occurred at first flower, B-Nine was more effective than Sumagic. Plant SOD when PGRs were applied had no effect on flowering or plant quality of ‘Moonbeam’ coreopsis and minimal effect on ‘Early Sunrise’ coreopsis or ‘Goldsturm’ rudbeckia.

scholarly journals Growth Retardant Use on Herbaceous Perennials Grown Under Night-Interrupted Lighting Outdoors in the Southern United States

2010 ◽  
Vol 28 (2) ◽  
pp. 96-102
Author(s):  
Gary J. Keever ◽  
J. Raymond Kessler ◽  
James C. Stephenson
Keyword(s):  
United States ◽  
Stem Elongation ◽  
Height Growth ◽  
Southern United States ◽  
Growth Retardants ◽  
Flower Bud ◽  
Herbaceous Perennials ◽  
Natural Photoperiod ◽  
One Year ◽  
The One

Abstract A study was conducted in 2002 and 2003 to determine if growth retardants could be used to suppress stem elongation of ‘Moonbeam’ coreopsis (Coreopsis verticillata L. ‘Moonbeam’) and ‘Goldsturm’ coneflower (Rudbeckia fulgida Aiton ‘Goldsturm’) when grown outdoors under nursery conditions in the southern United States without negating the benefits of earlier flowering from night-interrupted lighting (NIL). Night-interrupted lighting accelerated flowering of both cultivars without adversely affecting flower and flower bud counts or plant quality. However, plants grown under NIL generally were taller than plants grown under natural photoperiod (NP). When several PGRs [Cutless, B-Nine, B-Nine/Cycocel, Bonzi (2002 only), and Sumagic (2003 only)] were applied to plants under NIL, results varied with PGR type and concentration and year. Height of ‘Moonbeam’ coreopsis was effectively suppressed by 5000 or 7500 ppm B-Nine + 1500 ppm Cycocel in both years of the study and with 40 or 60 ppm Sumagic in the one year it was tested. Higher concentrations of Cutless and B-Nine suppressed height growth in 1 of 2 years, while Bonzi was ineffective. None of the PGR types or concentrations suppressed height growth of ‘Goldsturm’ coneflower to the level of the NP control in 2002. However, in 2003 when an additional application of Cutless and B-Nine were made, and Bonzi was replaced with Sumagic, applications of Cutless, B-Nine, B-Nine/Cycocel, and Sumagic all resulted in heights similar to or less than that of plants under NP with minimal effects on time to flower or flower and flower bud counts.

Effect of cutting date and frequency on yield and quality of kudzu in the southern United States

2003 ◽  
Vol 58 (2) ◽  
pp. 178-183 ◽  
Author(s):  
T.H. Terrill ◽  
S. Gelaye ◽  
S. Mahotiere ◽  
E. A. Amoah ◽  
S. Miller ◽  
...  
Keyword(s):  
United States ◽  
Southern United States ◽  
Yield And Quality

scholarly journals Night-Interrupted Lighting Accelerates Flowering of Herbaceous Perennials Under Nursery Conditions in the Southern United States

2006 ◽  
Vol 24 (1) ◽  
pp. 23-28
Author(s):  
Gary J. Keever ◽  
J. Raymond Kessler ◽  
James C. Stephenson
Keyword(s):  
United States ◽  
Plant Quality ◽  
Southern United States ◽  
Herbaceous Perennials ◽  
Natural Photoperiod ◽  
Quality Rating ◽  
Second Year ◽  
One Year ◽  
Photoperiod Control

Abstract Night-interrupted lighting (NIL) outdoors in a southern nursery setting was evaluated as a system for accelerated production of herbaceous perennials requiring long days to flower. Treatments were NIL beginning February 1, February 15, March 1, or March 15, and a natural photoperiod control. Compared to plants under the natural photoperiod and depending upon initiation of NIL treatment and year, NIL accelerated and increased flowering of ‘Moonbeam’ coreopsis (Coreopsis verticillata L. ‘Moonbeam’) 7 to 36 days and 20 to 244%, ‘Early Sunrise’ coreopsis (Coreopsis grandiflora Hogg ex Sweet. ‘Early Sunrise’) 3 to 20 days and 26 to 64%, ‘Sunray’ coreopsis (Coreopsis grandiflora Hogg ex Sweet. ‘Sunray’) 6 to 13 days and 21 to 44%, ‘Autumn Joy’ stonecrop (Sedum x ‘Autumn Joy’) 26 to 57 days and 200 to 300%, and ‘Blue Queen’ salvia (Salvia x superba Stapf ‘Blue Queen’) 7 to 12 days and 56 to 83%. Flowering of ‘Red Beauty’ obedient plant (Physostegia virginiana (L.) Benth. ‘Red Beauty) was accelerated 20 to 54 days; however, inflorescence counts decreased 38 to 46% in one year and was not affected by treatments in the second year. Plants of all cultivars, except ‘Autumn Joy’ sedum and ‘Red Beauty’ obedient plant, were taller when exposed to NIL than when grown under the natural photoperiod, however plant quality rating of all cultivars was as high or higher under NIL.

scholarly journals Enhance Growth and Flower Quality of Chrysanthemum indicum L. with Application of Plant Growth Retardants

Horticulturae ◽  
2021 ◽  
Vol 7 (12) ◽  
pp. 532
Author(s):  
Endre Kentelky ◽  
Zsolt Szekely-Varga ◽  
János Bálint ◽  
Adalbert Balog
Keyword(s):  
Plant Growth ◽  
Ornamental Plants ◽  
Growth Inhibitors ◽  
Growth Retardants ◽  
Chrysanthemum Indicum ◽  
Negative Effect ◽  
Plant Growth Retardants ◽  
Flower Quality ◽  
Plant Growth Inhibitors

Ornamental plants are cultivated worldwide. Chrysanthemum is classified as one of the most important cut and potted flowers in most of the countries. The consumer’s expectation is to find small–compact, and full of inflorescences plants. To meet these demands, growers are tending to use plant growth retardants. Three Chrysanthemum indicum L. varieties (‘Smola White’, ‘Arber’ and ‘Vienna White’) were assessed by using four plant growth regulators (PP–Bumper 250 EC; CC–Stabilan SL; MP–Medax Top SC; and PD–Toprex SC). Results indicate that treated plants show significant decrease in the assessed parameters, although in some cases growth could be a variety–dependent factor. It can also be concluded that retardants inhibit chrysanthemum growth. PD treatments greatly inhibited the growth of the plant, and also had a negative effect on inflorescences. In conclusion, the present work strengthens the possibility of using retardants as plant growth inhibitors in Chrysanthemum cultivation.

scholarly journals (245)`WhipperSnapper', a Dual-purpose Southern pea for the Production of Both Snaps and Fresh-shell Peas

HortScience ◽  
2005 ◽  
Vol 40 (4) ◽  
pp. 1018B-1018
Author(s):  
Richard L. Fery ◽  
Blair Buckley ◽  
Dyremple B. Marsh
Keyword(s):  
United States ◽  
Plant Breeding ◽  
Southern United States ◽  
Dual Purpose ◽  
Snap Beans ◽  
Yellow Color ◽  
Seed Characteristics ◽  
Single Variety

Home gardeners and farmers in the southern United States have traditionally grown southernpeas to produce both fresh-shell peas and immature, fresh pods, or snaps. American growers do not presently have access to a single variety that is ideally suited for both uses. In 1988, a plant breeding effort was initiated to incorporate genes conditioning superior yield and seed characteristics of Asian “vegetable cowpeas” into American snap-type southernpeas. This effort resulted in the development of `WhipperSnapper', which is suited for use as a dual-purpose variety that can be used to produce both snaps and fresh-shell peas. Typical ready-to-harvest `WhipperSnapper' snaps are green colored, 6.4 mm in diameter, 7.6 mm in height, and 24 cm long. Typical mature-green pods suitable for fresh-shell harvest exhibit an attractive yellow color, are 25 cm long, and contain 14 peas. Fresh peas are cream-colored, kidney-shaped, and weigh 24.5 g per 100 peas. Dry pods exhibit a light straw color, and the dry peas have a smooth seedcoat. The total `WhipperSnapper' yield of snaps can be as much as 62% greater than the total snap yield of the snap-type variety `Bettersnap'; pea yield can be as much as 69% greater. The quality of `WhipperSnapper' seed is excellent and much superior to that of `Bettersnap'. `WhipperSnapper' can be used by home gardeners and market gardeners to produce abundant quantities of snaps and fresh-shell peas during seasons too hot for successful culture of such table legumes as snap beans. `WhipperSnapper' also has the potential for use as a mechanically harvested source of snaps for use by food processors in mixed packs of peas and snaps.

scholarly journals Accelerated Flowering of Herbaceous Perennials Under Nursery Conditions in the Southern United States

2001 ◽  
Vol 19 (3) ◽  
pp. 140-144
Author(s):  
Gary J. Keever ◽  
J. Raymond Kessler ◽  
James C. Stephenson
Keyword(s):  
United States ◽  
Plant Height ◽  
Plant Quality ◽  
Southern United States ◽  
Late Winter ◽  
Flower Bud ◽  
Herbaceous Perennials ◽  
Natural Photoperiod

Abstract A study was conducted to determine the effects of night-interrupted (NI) lighting initiated at different times in late winter on several herbaceous perennials produced outdoors in a southern nursery setting. Treatments were NI lighting beginning February 1, February 15, March 1, March 15, and a natural photoperiod. NI lighting accelerated flowering in ‘Goldsturm’ coneflower (Rudbeckia fulgida Ait. ‘Goldsturm’) 26–46 days in 1999 and 51–75 days in 2000, and in ‘Coronation Gold’ yarrow (Achillea x ‘Coronation Gold’) 2–9 days in 1999 and 2–11 days in 2000. Flower and flower bud counts increased 82–100% in ‘Coronation Gold’ achillea in 1999, 44–51% in ‘Butterfly Blue’ scabious (Scabiosa columbaria L. ‘Butterfly Blue’) and 100–151% in ‘Alaska’ shasta daisy (Leucanthemum x superbum Bergmans ex. J. Ingram ‘Alaska’) compared to counts of plants under natural photoperiod. With few exceptions, plant height increased under all NI lighting treatments, but in only ‘Goldsturm’ coneflower did it reduce plant quality. Clump verbena (Verbena canadensis L.) was minimally affected by NI lighting, and speedwell (Veronica spicata L. ‘Sunny Border Blue’) was not affected at all.

scholarly journals HEIGHT CONTROL OF HERBACEOUS PERENNIALS FORCED USING NIGHT-INTERRUPTED LIGHTING UNDER NURSERY CONDITIONS

HortScience ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 893f-894
Author(s):  
Gary J. Keever ◽  
J. Raymond Kessler
Keyword(s):  
Plant Growth ◽  
Plant Height ◽  
Control Plant ◽  
Growth Retardants ◽  
Natural Control ◽  
Height Control ◽  
Herbaceous Perennials ◽  
Quality Rating ◽  
Plant Growth Retardants ◽  
Outdoor Nursery

In previous studies, night-interrupted lighting (NIL) promoted earlier flowering of summer-blooming herbaceous perennials grown under outdoor nursery conditions in the southeastern U.S. However, NIL promoted excessive plant height, thus reducing product quality. Our objective was to control plant height of Coreopsis grandiflora `Early Sunrise' (ES) and Rudbeckia fulgida `Goldsturm' (RG) grown under NIL with plant growth retardants (PGR) without offsetting earlier flowering promoted by NIL. Treatments under NIL were three rates of daminozide, daminozide plus chloromequat, flurprimidol, uniconazole, and NIL and natural controls. Plant height was reduced 3% to 38% in ES and 8% to 31% in RG and time to visible bud was unchanged by all PGR treatments compared to the NIL control. Time to visible bud was unchanged in RG by all PGR treatments and flurprimidol in ES, but the remaining PGR treatments increased time to visible bud compared to the NIL control in ES. Only ES plants treated with daminozide and daminozide plus chloromequat at the two highest rates and all rates of uniconazole were similar in height to the natural control. RG plant heights with the two highest rates of flurprimidol and uniconazole and the highest rate of daminozide plus chloromequat were less than the natural control; heights of plants in the remaining PGR treatments were similar to the natural control. Quality rating was unchanged in RG but was increased in ES by all PGR treatments compared to the NIL control.

scholarly journals Summer Applications of Plant Growth Retardants Affect Spring Forcing of Hydrangeas

1992 ◽  
Vol 2 (2) ◽  
pp. 213-216 ◽  
Author(s):  
Douglas A. Bailey ◽  
Bernadette Clark
Keyword(s):  
Plant Growth ◽  
Plant Height ◽  
Residual Effect ◽  
Control Program ◽  
Growth Period ◽  
Shoot Elongation ◽  
Growth Retardants ◽  
Height Control ◽  
Control Programs ◽  
Plant Growth Retardants

Summer spray applications of 5000 ppm daminozide (1× or 2×), 62 ppm paclobutrazol (1× or 2×), or 5 ppm uniconazole (1× or 2×) were applied to seven cultivars (Böttstein, Enziandom, Kasteln, Mathilde Gütges, Merritt's Supreme, Red Star, and Schenkenburg) of florists' hydrangea [Hydrangea macrophylla subsp. macrophylla var. macrophylla (Thunb.) Ser.] to evaluate cultivar response to plant growth retardants (PGRs). Both daminozide treatments and the 2× uniconazole treatment effectively reduced plant height for all cultivars during the summer growth period; cultivars varied in response to the paclobutrazol treatments and the 1× uniconazole treatment. Daminozide and uniconazole treatments resulted in less elongation than all other treatments during forcing for most cultivars tested. Paclobutrazol treatments had no residual effect on shoot elongation during forcing of the cultivars tested. The 2× treatments of all PGRs decreased inflorescence diameter of some of the cultivars tested compared with nonsprayed controls. Results from this study indicate that 1) summer application of PGRs can have a residual effect on plant height and inflorescence diameter of hydrangeas during the spring greenhouse forcing phase; and 2) hydrangea cultivars differ significantly in response to the PGRs tested. Therefore, the need for height control during the spring forcing period of hydrangeas will vary with cultivar, and it will depend on how plants were treated the previous summer growing season. We recommend that producers of dormant hydrangeas provide records of their summer height control program to forcers so that height control programs during spring forcing can be adjusted appropriately.

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