• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.1
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• pp.131-142
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• 2020

Chrysnathemum stunt viroid (CSVd), a small, single-stranded, infectious RNA, has caused a severe problem in chrysanthemum in the world. In Korea, since CSVd was firstly observed in 1997, the disease has been spread throughout the whole country rapidly. In spite of the seriousness, few methods for control of CSVd have been known without prevention. The use of resistant cultivars is one of the most efficient approaches for overcoming CSVd disease in chrysanthemum cultivation. This study was carried out to identify chrysanthemum genetic resources for the resistance to chrysanthemum stunt viroid (CSVd). A total of 192 commercial cultivars including 167 spray and 25 standard chrysanthemum were screened with CSVd through grafting inoculation method. In most of the inoculated cultivars, typical disease symptoms, stunting of plant height, reduced flower size, and flower color bleaching, were induced. Several cultivars, however, were symptomless or showed delay in symptom expression. Of 192 chrysanthemum cultivars, two cultivars with less than 5% of the average reduction rate of plant height, 'Chiwerel' and 'Jeongheungdaesin', were rated as resistant. And six cultivars less than 20% inculding 'Inga' were rated as moderate resistant. The remaining 184 cultivars with a high level of reduction were rated as susceptible. We expect that these genetic resources can be used in crossbreeding programs for developing CSVd resistant cultivars of chrysanthemum.

• 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.

• 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.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.8-13
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• 1985

Egremont russet 사과 품종(品種)의 종자에 여러가지 종피(種皮) 파상(破傷)을 한 후 발아(發芽), 유아(幼芽), 유근(幼根)의 생장(生長)과 생리적(生理的)인 왜화(矮花)에 대(對)하여 조사한 결과 다음과 같은 결과를 얻었다. 자엽(子葉)의 크기를 1/2로 절단하고 종피(種皮)를 제거(除去)한 Egremont russet 사과 품종(品種)의 종자(種子)에 $GA_3$를 처리한 것은 평균발아율(平均發芽率)이 55%였으며 동일조건(同一條件)에서 대조구(對照區)는 45%였다. 그리고 종피(種皮)가 완전(完全)한 것과 종피파상(種皮破傷)을 한 구(區)에서는 낮았다. 유아장(幼芽長)은 종피(種皮)를 완전히 남긴 것과 파상(破傷)한 구(區)에 $GA_3$를 처리하였을 때 촉진(促進)되었으나 전체적(全體的)으로 볼 때 종피(種皮)를 제거(除去)한 구(區)에서 더 길었다. 그러나 유근장(幼根長)은 $GA_3$처리에 의(依)해서 억제(抑制)되었으나 유근(幼根)의 직경(直徑)은 더 커졌다. 그리고 생리적(生理的)인 왜화(矮花)는 종피(種皮)를 남긴 구(區)에서 발생(發生)되었으며 $GA_3$ 처리에 의(依)해 극복되지 않았다. 자엽(子葉)의 녹색화(綠色化) 속도는 종피(種皮)를 제거(除去)하고 자엽(子葉)의 크기를 1/2로 절단한 구(區)에서 촉진(促進)되었다.

• 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 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 Plant Pathology
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• v.14 no.6
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• pp.612-613
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• 1998

The nucleotide sequence of hop stunt viroid HHSVd) Kh strain was sequenced by the reverse transcription and polymerase chain reaction. It consists of 296 nucleotides, and differs by one nucleotide deletion of cytosine at the position of 295 from the HSVd-K strain which consists of 297 nucletoides.

• 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.50-58
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• 1992

Studies were conducted to determine the combined effect of uniconazole [(E) -1-(4-chlorophenyl)-4, 4-demethyl 2-(1,2,4 triazol-1-yl)-1-penten-3-ol] and silver thiosulfate $[Ag {(S_2O_3)}^3\;_2-]$ (STS) on reduction of ozone injury in tomato plants(Lycopersicon esculentum Mill. 'Pink Glory'). Plants were given a 50ml soil drench of uniconazole at concentrations of 0, 0.001, 0.01 and 0.1 mg/pot at the stage of emerging 4th leaf. Two days prior to ozone fumigation, STS solution contained 0.05% Tween-20 was also sprayed at concentrations of 0, 0.3 and 0.6 mM. Uniconazole at 0.01 mg/pot and STS at 0.6 mM were effective in providing protection against ozone exposure(20h at 0.2ppm) without severe retardation of plant height and chemical phytotoxicity, respectively. Combined treatment with uniconazole, STS significantly reduced ozone injury at the lower concentration than a single treatment with uniconazole or STS. Uniconazole treatment reduced plant height, stem elongation and transpiration rate on a whole plant level and increased chlorophyll concentration. STS did not give any effect on plant growth and chlorophyll content but increased transpiration rate in non-ozone-fumigated plants. Ethylene production in the leaves of ozone-fumigated plants was decreased by uniconazole and STS pretreatment, but there was no protective effect on epinasty of leaves in uniconazole-treated plants. STS increased ethylene production in non-ozone-fumigated plants, but it significantly reduced the degree of epinasty and defoliation of cotyledons when plants were exposed to ozone. Uniconazole slightly increased superoxide dismutase and peroxidase activities. But STS showed little or no effects on such free radical scavengers. Day of flowering after seeding was shortened and percentages of fruit set were increased by uniconazole treatment. STS was highly effective on protecting reduction of fruit set resulting from ozone fumigation. These results suggest that combined use of uniconazole and STS should provide miximum protection against ozone injury without growth retardation resulting in yield loss.