scholarly journals Ornamental Cabbage and Kale Cultivar Comparison Study: Growth Characteristics and Response to Daminozide and Uniconazole Foliar Sprays

2001 ◽  
Vol 11 (3) ◽  
pp. 376-380 ◽  
Author(s):  
James L. Gibson ◽  
Brian E. Whipker

Twenty-six ornamental cabbage and kale (Brassica oleracea var. acephala) cultivars were grown in 8-inch (20.8-cm) diameter pots during Fall 1998 to classify their foliage traits and determine their response to the plant growth regulator (PGR) daminozide. Cultivar vigor was classified by height. Foliage characteristics were described and cultivars of ornamental cabbage, notched ornamental kale, and curly ornamental kale were selected for retail or wholesale markets based on the shortest number of days until a significant center color change, the largest center color diameter, and attractive foliage characteristics. Two cultivars treated with 2,500 ppm (mg·L-1) daminozide and eight cultivars treated with 5,000 ppm were significantly smaller in height compared to nontreated plants. Plants were treated 6 weeks after sowing, and the response to the PGRs may have been diminished by the age of the plant. Therefore, to further investigate PGR efficacy, seven outstanding cultivars selected in 1998 were treated with 5,000 ppm daminozide or 5 ppm uniconazole 14 days after potting (4 weeks after sowing) in Fall 1999. Greater control was observed with daminozide at 5,000 ppm in 1999 with a 13% smaller plant height as compared to 9% in 1998, when compared to the nontreated control. For greater height control, PGR applications to ornamental cabbage and kale should be applied 4 weeks after sowing.

HortScience ◽  
2000 ◽  
Vol 35 (4) ◽  
pp. 565E-565d ◽  
Author(s):  
James L. Gibson ◽  
Brian E. Whipker

Twenty-six ornamental cabbage and kale (Brassica oleracea var. acephala L.) cultivars were transplanted into 20.8-cm (8-inch) pots in Fall 1998 to classify their foliage traits and determine their response to the plant growth regulator (PGR) daminozide. Daminozide foliar sprays were applied at 0, 2500, or 5000 mg·L–1 (ppm) 3 weeks after potting. Two cultivars treated with 2500 mg.L-1 and eight cultivars treated with 5000 mg·L–1 were significantly smaller in height when compared to the nontreated plants. Using the Range/lsd formula, the vigor of the cultivars was classified by height. Foliage characteristics were described and cultivars of ornamental cabbage, notched ornamental kale, and curly ornamental kale were selected based on the shortest number of days until a significant center color change and the largest center color diameter. In Fall 1999, recommended cultivars selected in 1998 were treated with daminozide at 5000 mg·L–1 or uniconazole at 5 mg·L–1 14 days after potting, plus a nontreated control. All cultivars responded similarly to the PGRs with greater control being observed with daminozide with a smaller plant height of 13% as compared to 6% for uniconazole. For effective height control, PGR applications to ornamental cabbage and kale should be applied 2 weeks after potting.


2000 ◽  
Vol 10 (1) ◽  
pp. 151-153 ◽  
Author(s):  
Brian E. Whipker ◽  
Shravan K. Dasoju ◽  
Michael R. Evans

Drench applications of paclobutrazol or uniconazole were applied at doses of 0, 0.0025, 0.005, 0.01, 0.02, or 0.04 mg a.i./pot (28,350 mg = 1.0 oz) to vegetatively propagated `Aurora', `Medallion Dark Red', and `Pink Satisfaction' geranium (Pelargonium ×hortorum L.H. Bailey). Geranium total plant height, leaf canopy height, and plant diameter responded similarly to drench applications of either paclobutrazol or uniconazole. There was a significant quadratic relationship between plant growth regulator (PGR) dose and total plant height and leaf canopy height for `Aurora' and `Medallion Dark Red', with total plant height and leaf canopy height being shorter as paclobutrazol or uniconazole doses increased up to 0.02 mg. However, doses of ≥0.02 mg had little additional effect on total plant height and leaf canopy height. Most of the total height control achieved by the use of PGRs was primarily due to a reduction of leaf canopy height, rather than inflorescence height. Doses of 0.005 to 0.01 mg of either PGR produced marketable sized potted plants of `Medallion Dark Red' and `Pink Satisfaction'. `Aurora', which was the most vigorous cultivar, required doses of 0.01 or 0.02 mg of either paclobutrazol or uniconazole to produce marketable sized potted plants.


2005 ◽  
Vol 15 (2) ◽  
pp. 370-373 ◽  
Author(s):  
Brian A. Krug ◽  
Brian E. Whipker ◽  
Ingram McCall ◽  
John M. Dole

Preplant bulb soaks of ancymidol, flurprimidol, paclobutrazol, and uniconazole; foliar sprays of flurprimidol; and substrate drenches of flurprimidol, paclobutrazol, and uniconazole were compared for height control of `Prominence' tulips (Tulipa sp.). Height control was evaluated at anthesis in the greenhouse and 10 days later under postharvest conditions. Substrate drenches of ancymidol, flurprimidol, and paclobutrazol resulted in adequate control using concentrations of 0.5, 0.5, and 1 mg/pot a.i. (28,350 mg = 1 oz), respectively. At these concentrations, ancymidol drenches cost $0.06/pot and paclobutrazol drenches $0.03/pot. Since flurprimidol is not yet available and no price is available, growers will need to assess the cost compared to ancymidol and paclobutrazol. Flurprimidol foliar sprays at <80 mg·L–1 (ppm) were ineffective in controlling height during greenhouse forcing, but during postharvest evaluation 80 mg·L–1 resulted in 14% shorter plants than the untreated control. Preplant bulb soaks of flurprimidol, paclobutrazol, and uniconazole at concentrations of 25, 50, and 10 mg·L–1, respectively, effectively controlled plant height. Preplant plant growth regulator soaks are a cost-effective method of controlling plant height of tulips because of the limited amount of chemical required to treat a large quantity of bulbs.


2003 ◽  
Vol 13 (1) ◽  
pp. 132-135 ◽  
Author(s):  
James L. Gibson ◽  
Brian E. Whipker

Vigorous osteospermum (Osteospermum ecklonis) cultivars Congo and Wildside received foliar sprays of daminozide or daminozide + chlormequat (Expt. 1). Both cultivars responded similarly to the plant growth regulator (PGR) treatments. Only a limited amount of plant height control occurred using 5,000 mg·L-1 (ppm) daminozide + 1,500 mg·L-1 chlormequat or 5,000 mg·L-1 daminozide + 3,000 mg·L-1 chlormequat. Flowering was delayed, phytotoxicity was observed, while peduncle length increased, suggesting that higher concentrations of daminozide or chlormequat may or not be effective at any concentration and may result in increased phytotoxicity. In Expt. 2, `Lusaka' received foliar sprays or substrate drenches of paclobutrazol or uniconazole. Foliar sprays ≤80 mg·L-1 paclobutrazol or ≤24 mg·L-1 uniconazole were ineffective in controlling plant growth. Substrate drenches of paclobutrazol (a.i.) at 8 to 16 mg/pot (28,350 mg = 1.0 oz) produced compact plants, but at a cost of $0.23 and $0.46/pot, respectively, would not be economically feasible for wholesale producers to use. Uniconazole drenches were effective in producing compact `Lusaka' osteospermum plants. Uniconazole drench concentrations of 0.125 to 0.25 mg/pot were recommended for retail growers, while wholesale growers that desire more compact plants should apply a 0.25 to 0.5 mg/pot drench. Applying uniconazole would cost $0.06 for a 0.25 mg drench or $0.12 for a 0.5 mg drench.


1991 ◽  
Vol 116 (2) ◽  
pp. 191-200 ◽  
Author(s):  
E. M. White

SUMMARYApplications of nitrogen and a plant growth regulator (mepiquat chloride and ethephon) were used to manipulate stem structure and induce differing degrees of damage due to leaning and lodging in six cultivars of winter barley grown in Belfast, UK, in 1986/87. Weighted incidences of leaning and lodging were combined to give an index indicating damage susceptibility of the cultivars. The index was very high (70) in Pipkin and ranged between 1 and 18 in the other cultivars. Differences between cultivars in number of internodes, plant height and stem weight did not explain their differences in resistance to damage. However, dry weight per unit length ranged from 2·35 and 2·34 mg/mm in the strongest cultivars, Panda and Jennifer, respectively, to 1·75 mg/mm in the weakest cultivar, Pipkin.Nitrogen application increased plant height but did not affect dry weight/main stem, so that dry weight/unit length of stem decreased. The growth regulator treatments reduced plant height and although dry weight/stem did not decrease significantly, dry weight/unit length of stem was similar in treated and untreated plots.Dry weight/unit length has potential as an objective indicator of straw strength in winter barley cultivars and could be used in cultivar evaluation in the absence of damage in field trials.


1996 ◽  
Vol 10 (4) ◽  
pp. 851-855
Author(s):  
C. Dale Monks ◽  
Michael G. Patterson ◽  
Malcolm Pegues

Field experiments were conducted in Alabama from 1992 through 1994 to evaluate the potential of the methyl ester of bensulfuron applied at sublethal rates as a plant growth regulator for reducing plant height and boll rot in cotton. Bensulfuron at 0.017 and 0.034 g ai/ha or mepiquat chloride at 10 g ai/ha was applied POST alone at the pinhead square or early-bloom stage of cotton growth or sequentially at 0.017 followed by (fb) 0.017 g/ha, 0.034 fb 0.034 g/ha of bensulfuron and 5 fb 5, 10 fb 10, 10 fb 20, or 20 fb 20 g/ha of mepiquat chloride. Mepiquat chloride had no effect on yield in 1992 and 1994 but decreased yield when applied sequentially in 1993. Bensulfuron was generally detrimental to first position fruit retention, and it delayed maturity. Treatments that reduced plant height did not reduce boll rot. Bensulfuron treatments that reduced plant height also reduced yield; therefore, the potential for its use as a growth regulator in cotton appears limited.


2020 ◽  
Vol 100 (6) ◽  
pp. 653-665
Author(s):  
B.D. Tidemann ◽  
J.T. O’Donovan ◽  
M. Izydorczyk ◽  
T.K. Turkington ◽  
L. Oatway ◽  
...  

Malting barley is important in western Canada, yet many malting cultivars do not meet malt quality standards, in part due to lodging. Lodging can decrease barley yield and quality thereby reducing the acceptability for malting. In other countries, plant growth regulator (PGR) applications are used to mitigate lodging. Chlormequat chloride (chlormequat), trinexapac-ethyl (trinexapac), and ethephon were tested at five locations over 3 yr in western Canada for their ability to limit lodging, as well as their effects on yield, agronomic traits, and pre-malt quality characteristics. PGR applications occurred between Zadoks growth stage (GS) 30–33 for chlormequat and trinexapac and GS 37–49 for ethephon. Seeding rates of 200, 300, and 400 seeds m−2 of CDC Copeland barley were used to increase the likelihood of lodging. Increased seeding rate decreased tillers per plant, height, days to maturity, kernel protein, and kernel weight. Ethephon increased the number of tillers per plant and decreased plant height, kernel plumpness, and kernel weight. Trinexapac decreased plant height and kernel weight. Days to maturity was investigated across site-years, with ethephon increasing maturity in 60% of comparisons. Trinexapac and chlormequat had limited effects on maturity. Lodging was investigated across site-years, with trinexapac showing the largest number of lodging reductions and scale of reductions. Ethephon reduced lodging in 36% of comparisons, while chlormequat had inconsistent effects. None of the products affected yield or grain protein. The results suggest PGRs may not be the solution to lodging for CDC Copeland barley on the Canadian Prairies; however, trinexapac shows the most promise of the products tested.


1992 ◽  
Vol 72 (4) ◽  
pp. 1153-1156 ◽  
Author(s):  
K. J. Kirkland

A 3-yr field experiment was conducted at the Scott Experimental Farm to determine the effect of the growth regulator, triapenthenol, on the growth and development of Argentine canola (Brassica napus L.). Triapenthenol reduced plant height 25–45 cm under optimal growing conditions. Increases in yield, branches and total pods were observed. Application at the bud stage was more effective than earlier treatment in the rosette. It was concluded that triapenthenol application to canola could be a useful management tool, particularly under optimal growing conditions.Key words: Canola, growth regulator, RSW-0411, lodging


2018 ◽  
Vol 51 (4) ◽  
pp. 60-72
Author(s):  
E.K. Eifediyi ◽  
F.O. Ogedegbe ◽  
N.B. Izuogu ◽  
C.A. Adedokun ◽  
A. Katibi ◽  
...  

Abstract The Guinea savannah zone of Nigeria is beset by increasing population and infrastructural development, thereby putting pressure on available land with rapidly declining fertility due to low organic matter content, soil erosion, high temperature and seasonal bush burning. Sesame is cultivated in this zone and the yield has remained very low, compared to yield in other parts of the world. This could be attributed to poor nutrient status and poor cultural practices used by peasant farmers. A field experiment was conducted at the Teaching and Research Farm, University of Ilorin, Nigeria, in a southern Guinea savannah zone in 2015 and repeated in 2016 cropping season to determine the effects of 2,4-Dichlorophenoxyacetic acid (2,4-D), a plant growth regulator and NPK fertilizer on the growth and yield of sesame. The experiment was laid out as a factorial arrangement, fitted into a randomized complete block design replicated thrice. The factors imposed were 2,4-D (0, 5 and 10 ppm ha−1) and NPK 15:15:15 (0, 100, 200 and 300 kg ha−1). Data were collected on vegetative traits (plant height, number of leaves, leaf area) and yield components (number of capsules per plant; yield per plant and per hectare). The data were subjected to analysis of variance (ANOVA) using the Genstat statistical package 17th edition and significant means were separated by using the least significant difference at 5% level of probability. The result revealed that using plant growth regulator and NPK fertilizer had significant effects (p<0.05) on plant height (151 cm) and yield per hectare (530 kg/ha). The qualitative and quantitative analysis of the seeds further reaffirmed the presence of bioactive compounds, such as saponins, tannins, flavonoids and phenolic compounds, which are important health promoting food in the seeds.


HortScience ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 886d-886
Author(s):  
Todd J. Cavins

Anti-gibberellin plant growth regulators (PGRs) not only affect cell elongation, but other biochemical processes. The experimental PGR A-1699 DF was evaluated for efficacy of height and width control as well as effect on flower petal pigmentation. While the active ingredient in A-1699 DF has proven effective for height control on several crops, that was not observed on Impatiens `Accent Cranberry' in this study. However, A-1699 DF did affect flower petal pigmentation. A-1699 DF likely inhibited anthocyanin production that resulted in light pink versus cranberry flower petals observed on the control, Paczol, and B-Nine/Cycocel PGR applications.


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