• Horticultural Science & Technology
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• v.19 no.4
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• pp.574-578
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• 2001

The effects of seed soaking (8 and 24 hours) and foliar spray of plant growth retardants (daminozide, chlormequat and uniconazole) on growth control in zinnia were investigated. For seed soaking of 'Dream Land Rose', the changes in plant height was not affected by seed soaking time (8 and 24 hours), while it was severely suppressed by high concentration of chemicals tested. An application of $125mg{\cdot}L^{-1}$ uniconazole was most effective for plant height suppression. Flowering was promoted by all treatments of chemicals. However, for 'Dream Land Scarlet', plant height control at 24 hours seed soaking showed more effective than 8 hours, and all treatments of chemicals decreased plant height. Uniconazole gave the best result for plant height control. Flowering tended to be hastened by the treatment of chemicals. For foliar spray, plant height was remarkably decreased at high concentration of uniconazole. Flowering was promoted by chlormequat and uniconazole in both 'Dream Land Rose' and 'Dream Land Scarlet'. Also, daminozide decreased number of petals.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.139-146
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• 2003

This study was conducted to investigate the effects on the over-growth inhibition of fruit vegetables (tomato, cucumber, and hot pepper) seedling by the treatment of triazole-typechemicals and to select the most effective chemicals for the over-growth inhibition, and to investigate suitabla concentration treatment and times of the newly selected chemical. The triazole-type chemicals inhibited stem height more, the more the concentration is increased in any crops. The diniconazole showed the highest dwarfing ration, and the tebuconazole and hexaconazole are also good for dwarfing ratio. The diniconazole decreased the plant height of cucumber, tomato, and hot pepper as the concentration is increased. In cucumber, thc dwarfing ratio was 30% in the 5 mg${\cdot}L^{-1}$ treatment, and was 60% in thc l00 mg${\cdot}L^{-1}$ treatment. In tomato and hot pepper, the dwarfing ratio was 30% in the 25 mg${\cdot}L^{-1}$ treatment in any times. In diniconazole treatment, the cucumber and tomato should have 5 mg${\cdot}L^{-1}$ at the lst growth stage and the hot pepper should have 5 mg${\cdot}L^{-1}$ at the 2nd growth stage to obtain good seedlings.

• Korean Journal of Agricultural Science
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• v.19 no.2
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• pp.161-169
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• 1992

Studies were conducted to examine the effects of single or combined treatment of uniconazole [(E)-1-(4-chlorophenyl)-4, 4-dimethyl 2(1, 2,-4-triazol-1-yl)-1-penten-3-ol)] and silver thiosulfate (STS) on reducing ozone injury to snap beans (Phaseolus vulgaris L. 'Strike'). Two weeks after seeding, plants were given a soil drench of uniconazole(XE-1019) solution at concentrations of 0.001, 0.005 and 0.025 mg/pot, and then two days prior to ozone fumigation, 0.3 and 0.6 mM STS containing 0.01% Tween-20 were also sprayed. Uniconazole was effective in providing protection against ozone injury through increase activities of free radical scavengers such as superoxide dismutase (SOD) and peroxidase (POD) as well as the increase of chlorophyll content and stomatal resistance resulted from plant growth retardation. The phytoprotective effects of STS seemed to be related to its properly of blocking the ethylene action and increasing activities of SOD and POD. Even at low concentrations, a combined treatment with uniconazole drench, STS spray significantly reduced ozone injury compared to single application.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.2
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• pp.222-232
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• 1976

Two different cultivars of barley, with either the ordinary-level or double-strength nitrogen application, were grown in two districts simultaneously, in order to study the extent of dwarfing in plant height, lodging and grain-yield increase with ethylene-releasing agents (Ethrel and dl-methionine alone or in combination). The shorter the plant height, the less the extent of lodging and the grain yield there were. With 500ppm Ethrel, 10% grain-yield increase was attained without showing apparent lodging, irrespective of the level of nitrogen applied. The double-strength nitrogen application resulted in severe lodging more than the ordinary-level and control, and lower grain yield accordingly. Consideration for importance of barley lodging in Korea today and the controlling measure with ethylene treatment for dwarfing, and yield increase by increased nitrogen application, were discussed.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.343-347
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• 2012

The purpose of this study was to examine the dwarfing effect in variable temperature treatments on 1-year-old and 3-year-old Chloranthus glaber. The plants grown in four difference growth chamber under a mean light intensity $500{\pm}20$ lux, RH of $40{\pm}5%$, and temperature of $5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, and $20^{\circ}C$ for 120 days from January 3, 2011. And then they were moved into a glass house (50% shading). In 1-year-old seedlings, the rate of plant height elongation was lowest at $5^{\circ}C$, but plant growth was not good. The number of leaves and leaf width were highly increased by $10^{\circ}C$ treatment although the plant height was slightly increased. Also the plant height of $15^{\circ}C$ and $20^{\circ}C$ was decreased and defoliation was started from the bottom leaves. Thus, $10^{\circ}C$ treatment was thought to be the most appropriate for dwarfing effect of 1-year-old seedlings. In 3-year-old seedlings, the plant height tended to increase with temperature, and growth pattern showed a similar trend between $5^{\circ}C$ and $10^{\circ}C$, $15^{\circ}C$ and $20^{\circ}C$. The number of leaves increased the most at $5^{\circ}C$. Lateral branches per node were mainly occurred at $5^{\circ}C$ and $10^{\circ}C$, whereas they almost didn't happen at $15^{\circ}C$ and $20^{\circ}C$. Flowering rate at $5^{\circ}C$ and $10^{\circ}C$ reached more than 90% and 60%, respectively, but it was too low at $15^{\circ}C$ and $20^{\circ}C$ until the end of August. From these results, it could improve plant quality of 1-year-old and 3-year-old Chloranthus glaber making compact potted plants when temperatures were maintained at $10^{\circ}C$ and $5^{\circ}C$, respectively.

• Korean Journal of Environmental Agriculture
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• v.11 no.1
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• pp.41-49
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• 1992

To determine the efficacy of uniconzaole[(E)-1-(4-chlorophenyl)-4,4-dimethy 2-(1,2,4-triazol-1-yl)-1-penten-3-ol)](XE-1019) as a phytoprotectant against $O_3$ injury in tomato plants(Lycopersicon esculentum Mill. 'Pink Glory'), plants were given a 50ml soil drench of uniconazole solution at concentrations of 0.001, 0,01, 0.1 and 0.2mg/pot thirteen days prior to $O_3$ fumigation. All four uniconazole concentrations were effective in providing protection against $O_3$ exposure(16h at 0.3 ppm). Uniconazole treatment above 0.001 mg/pot significantly reduced stem elongation, leaf enlargement, leaf area and fresh weight of plant, whereas increased chlorophyll concentration. Transpiration rate on a whole plant basis was reduced by uniconazole treatment and $O_3$ exposure. Uniconazole reduced ethylene production induced by $O_3$ injury but had little or no effect on defoliation of cotyledons and leaf epinasty. Activities of peroxidase (POD) and superoxide dismutase(SOD) were slightly increased by application of uniconazole. With increasing exposure time, $O_3$ increased POD activity but decreased SOD activity. The phytoprotective effects of uniconazole were diminished by applying gibberellin at $10{\sim}20$ ppm. These results suggest that the phytoprotective effects of uniconazole are related to its role of increasing activities of free radical scavengers such as POD and SOD, in addition to growth-retardation as an anti-gibberellin.

• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.243-248
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• 2000

This study was conducted to evaluate the effects of weed control and lodging reduction in the cultivation of buckwheat. The effect of weed control was significant. In the herbicide plot, nevertheless, grain yield and plant height were more decreased than habitual and vinyl mulching plots. Therefore, the application of herbicide was considered unnecessary in buckwheat cultivation having short growth period. In the habitual plot, dominant weed species are Digitaria sanguinalis, Erigeron annuus, E. canadensis, Setaria viridis, and Stellaria alsine var. undulata. On the effect of plant dwarf agent, C.C.C. and TIBA, plant height became shorter than habitual plot but the grain yield decreased. The latter tip pinching time, the less in grain yield which indicate tip pinching is ineffective in grain yield and lodging reduction. Among the wild species and cultivars of Fagopyrum, F. urophyllum was differentiated into xylem and phloem tissues indicating woody plant. Stem hardness of this species was the hardest as 625,110,000 dyne/cm$^2$which is at least 3.5 times harder than F. esculentum cv. Suwon #12. Therefore, it needs that the woody habitat gene of F. urophyllum is transfered into other cultivars in buckwheat breeding strategy.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.564-567
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• 2001

This experiment investigated the dwarfing effect of daminozide and chlormequat to produce high quality of spray chrysanthemum. Long neck of cut-chrysanthemum break easily. Peduncle length of the cultivar 'Biarittz' and 'Vyking' were retarded by the foliar spray treatment of $1500mg{\cdot}L^{-1}$ daminozide. Daminozide application did not affect plant growth of 'Biarittz' and 'Vyking'. However, the number of days to flowering was delayed by 3 days by daminozide application of 'Biarittz'. Length of cut flowers of 'Vyking' was decreased by the application of daminozide, while chlormequat did not affect dwarfing of peduncle length in spray chrysanthemum.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.81-88
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• 2011

Effect of concentrations of different plant growth retardants (PGRs) supplied to a recirculated nutrient solution in an ebb and flow system on the growth and development of potted Spathiphyllum 'Top-Pin' and 'Mini' was examined. Plants were planted in 10 cm diameter plastic pots filled with a mixture of peat moss and perlite (1 : 1, v/v) on 30 June 2005 and grown until 23 Sep. 2005. In a closed ebb and flow system, 50, 200, 350, $500mg{\cdot}L^{-1}$ daminozide (B-9), 10, 40, 70, $100mg{\cdot}L^{-1}$ paclobutrazol (Boundy), 5, 15, 25, $35mg{\cdot}L^{-1}$ ethephon (Florel), and 1, 4, 7, $10mg{\cdot}L^{-1}$ uniconazole (Sumagic) were supplemented to a nutrient solution at the initiation of experiment. On every irrigation, the nutrient solution containing PGRs was supplied at a 2 cm depth and kept for 15-20 minutes. The surplus nutrient solution was drained back into the tank for next irrigations. Paclobutrazol gave the most pronounced effect in inhibition of stretchiness. The greatest reduction of leaf length, fresh and dry weights of shoot, and elevated chlorophyll content were recorded in Spathiphyllum, with increasing paclobutrazol concentration. Daminozide concentration greater than $200mg{\cdot}L^{-1}$ resulted in minor stunting. The lowest concentration ($1mg{\cdot}L^{-1}$) of uniconazole showed greater leaf length, leaf width, and leaf petiole length than the control ($0mg{\cdot}L^{-1}$). Uniconazole concentration greater than $1mg{\cdot}L^{-1}$ resulted in similar plant growth as the plant in the control ($0mg{\cdot}L^{-1}$). High concentration ($35mg{\cdot}L^{-1}$) of ethephon resulted in the shortest leaf length, and the greatest chlorophyll content. Inhibition of stretchiness was observed even in the lowest concentration treatments. Among the PGRs, paclobutrazol was most effective in suppressing plant stretchiness. In both cultivars, ethephon and paclobutrazol, but not daminozide and uniconazole, significantly inhibited stretchiness. The results suggested that plant growth retardants (ethephon or paclobutrazol) selected in this study may be used as the most effective agents for inhibition of stretchiness in Spathiphyllum.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.568-573
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• 2001

The effects of foliar spray and soil drench application of triazole chemicals (diniconazole, myclobutanil, difenoconazole, tebuconazole, bitertanol, hexaconazole) on growth and flowering control in zinnia were investigated. For foliar spray application of tebuconazole, diniconazole and bitertanol on 'Dream Land Rose', plant height was decreased but tebuconazole gave the best result for dwarfing. Diameter, fresh and dry weights of flower were markably decreased at high concentration of tebuconazole. However, days to flowering was not affected by chemicals tested. For 'Dream Land Scarlet', plant height was decreased with all chemical treatments. Tebuconazole severely decreased plant height, in particulas. Diniconazole hastened flowering. For soil drench of 'Dream Land Rose', plant height was decreased by diniconazole and mycrobutanil, but diniconazole was more effective for plant height decrease. Flowering was hastened by diniconazole in both 'Dream Land Rose' and 'Dream Land Scarlet'. Plant height of 'Dream Land Scarlet' was decreased by all chemicals tested. Flowering was not occurred at $300mg{\cdot}L^{-1}$ myclobutanil with severe suppression of stem growth.