• Journal of Bio-Environment Control
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• v.11 no.2
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• pp.61-66
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• 2002

Double cropping system in a year in Kyoho grapes (Vitis labruscana L.) has currently been attempted in the plastic greenhouse. One of the problems in double cropping system is the promotion of bud break in summer season and shoot fertility. Effects of the control of soil moisture tension near the root zone and treatments of bud dormancy breaking agents on bud breaking in summer were examined to promote the bud break for the second fruiting. The lignification of shoots was induced in July or August by the control of soil moisture tension in root zone environment. The first shoot growth was almost the same as that in common plastic greenhouses. The highest bud break value appeared in the plot of cyanamide chemicals mixed with merit blue as over 75% bud break rate. The bud break rate in the discontinuing plot in irrigation showed significantly higher in bud break than that in the continuing plot in irrigation. Despite of the final high bud break rate, the time of bud break was irregular.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.49-55
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• 1984

Dormant one-year-old ginseng roots were subjected to a range of stratification temperatures and time to define effective limits to these parameters and to quantify their effect on terminating dormancy. Effective storage temperatures tested ranged from $0^{\circ}C\;to\;9^{\circ}C.$ A low percentage of roots produced tops with as few as 30 days in stratification; however, 75 to 90 days were required for 100 percent emergence. Days to emergence, after planting, decreased with increased days in storage thru the maximum storage time of 120 days. The number of days of dormancy was relatively constant, near 126.5 days, over the range of effective temperatures and acceptable storage times. The minimum period of dormancy was associated with 75 days in storage at $3^{\circ}C.$ Root growth rate, after emergence, was greatest following 105 days of stratification. The frequency distribution of emergence with days in stratification suggests the potential of selecting for strains of ginseng with low chilling needs for satisfying dormancy requirements.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.666-676
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• 2013

The study was carried out to examine the initial point of dormancy, breaking time of internal dormancy, and to find out the accumulated hours of low temperature (under $7.2^{\circ}C$ from $0.0^{\circ}C$ to $7.2^{\circ}C$) for bud-breaking. Over-all, the chilling requirement for breaking of internal dormancy in the commercial apple cultivars ('Fuji' and 'Tsugaru') and apple cultivars bred in Korea ('Hongro', 'Sunhong', 'Honggeum', 'Hongan', 'Hongso', 'Gamhong', 'Summer dream') at the Gunwi region for 4 years (from 2009 to 2012) was investigated. Also, the breaking time of internal dormancy in the field at the Gunwi region and the breaking time of dormancy if air temperature of Gunwi region rises $4^{\circ}C$ higher than the current one were investigated using the same data. The initial point of dormancy was set at the time when the lateral bud breaking did not occurred (when heading back cutting was done in the middle of terminal shoots). The occurrence of the breaking of internal dormancy was decided if the breaking of the terminal bud of bourse shoot occurred within 15 days or not in growth chamber. About 100 bourse shoots were collected by cultivar classification in early December every year and were stored at $5.0^{\circ}C$, and they were placed in growth chamber at one week interval. The chilling requirement of cultivars was expressed in accumulated hours in the field and in the growth chamber under $7.2^{\circ}C$ and $0.0-7.2^{\circ}C$ from the initial point of dormancy to the breaking time of internal dormancy. The results showed that the initial point of dormancy in selected cultivars could occur at the end of September. The breaking time of internal dormancy could occur from the end of January to the early of February. The accumulated hours under $7.2^{\circ}C$ for breaking of internal dormancy were 1,600-2,000 hours, while those of $0.0-7.2^{\circ}C$ were 1,300-1,800 hours. In comparing the different apple cultivars, the chilling requirement of the early flowering cultivars seemed lower than that of the late-flowering cultivars. Based on these results, if the air temperature of Gunwi region rises about $4.0^{\circ}C$ higher than the current one, the breaking time of internal dormancy will be delayed by 2-4 weeks.

• The Korean Journal of Ecology
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• v.25 no.2
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• pp.93-100
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• 2002

In order to analyze the life cycle of A. artemisiifolia var. elation dormancy and some environmental factors inducing germination of the seeds were examined. The results were as follows : Dormancy of fertile seeds was broken in part within a month after seed collection in case of adequate moisture and alternating temperature was also effective in breaking dormancy. The temperature range, which allow germination was 12℃ ∼ 32℃. Optimum temperature for germination was 24℃. The seed of A. artemisiifolia var. elatior was light-independent. The difference of storage period appeared to have no particular effect on the viability of seeds at any time during the 9-month storage period. In the increasing temperature(IT) regime, A artemisiifolia var. elatior seeds started to germinate at 16℃, showing the higher temperature the greater germination rate, the final germination percentage was 99.34%. On the other hand, in the decresing temperature(DT) regime, seeds began to germinate at 20℃ with the 1.34% germination. An induced dormancy occurred at 12℃ making the 5.34% fecal germination in the DT regime. Low temperature was more effective to break dormancy than higher temperature Seeds of A. artemisiifolia var. elatior seems to be germinated in mid to late autumn or germination delayed until following spring. The above results suggest these variation of germination response in diverse environmental factors seems to be a physiological strategy to maintain their existence and to reproduce in the extreme thermal variation.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.131-136
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• 2002

포도 2기작 재배는 아열대 지방인 대만 등에서 온난한 기후를 이용하여 실시되고 있다. 최근에 와서는 일본에서도 시설내 환경조절을 통하여 거봉포도를 한 나무에서 1년에 2회 생산하는 2기작 재배가 시도되고 있다. 2기작 재배 기술이 확립되면 수익의 증가가 기대됨과 동시에 하우스의 이용효율이 높아진다. 또한 수세도 쇠약해지지 않아 정상적인 가온재배에 비해서 수세 유지가 양호하다(Yamamoto, 1993). (중략)

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.137-142
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• 1983

The effects of various factors on germination of dormant Digitaria sanguinalis seeds were studied to obtain the basic informations on establishing an effective control method in upland crops. Germination of dormant seeds was most significantly promoted by light treatment, about 88-89%, and followed by the treatment of alternating temperatures (15 or 20$^{\circ}C$ to 35$^{\circ}C$), showing the similar effects like light. Removal of seed coats also increased germination of dormant seeds by 72%, next to the treatments of light and altering temperature. Potassium nitrate ($KNO_3$) at $10^{-2}M$ and concentrated sulfuric acid ($H_2SO_4$) treatment at the duration of 8 minutes resulted in 20% and 37.8% of germination of dormant seeds, respectively, which were significantly higher than that of the untreated control. Under the conditions of altering temperature, gibberellic acid (GA) at $10^{-3}M$ to $10^{-6}M$, benzylandenin (BA) at $10^{-4}$ to $10^{-7}M$ and their combination had no effect on breaking of dormant weed seeds, and instead inhibited the promotive effects induced by the alternating temperature. However, under the constant temperature at 35$^{\circ}C$ in dark, all these treatments increased germination as much as 20% over the untreated control.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.85-93
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• 1984

This research was carried out to study the seed dormancy of radishes which were used for summer vegetation. The differences of dormancy of cultivars, maternal effects, the effect of full day length to mother plants, and the effects of chemical treatments for breaking the seed dormancy were considered for this study. These results sere summarized as follows; 1. The germination percentage of 7 cultlvars sown just after harvest were as follows;SP70-:0, PS11-:37.5, GJ75-:75.5, JD127-:77.5, YH85-:81.0, M55-:96.5, and JC73-:98.0%. 2. The dormany of $F_1$ seed of radish was severe when SP70-was used for mother plant. 3. Germination behavior was different by the maturity of plants grown for seed production. The dormancy of seed harvested from immature field-grown plants sown Nov. 10 was deeper than mature plants sown Mar. 22. 4. The germination ratio of tire seed of SP70-radish was increased by treatment of full day length to tire mother plant during full period of growing or since first flowering stage, while that was 0% by treatment since yellow ripening stage. 5. GA 200 ppm+thiourea 0.2% treatment was most effective for breaking of radish seed dormancy.

• FLOWER RESEARCH JOURNAL
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• v.18 no.2
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• pp.93-97
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• 2010

The objective of this study was to investigate the effect of hot water and dipping times, and hot- PGR's solution on dormancy breaking of Lilium Oriental Hybrid 'Casa Blanca' and 'Siberia' bulblets regenerated in vitro. Hot-water treatments with distilled water were effective not sprouting rate but shortening of days to sprouting. While $100mg{\cdot}L^{-1}\;GA_{4+7}$ was effective in the dormancy breaking process of bulblets. The content of mitochondrial protein and fumarase activity were highest in bulblet of $100mg{\cdot}L^{-1}\;GA_{4+7}$ addition in hot water treatment. Therefore $GA_{4+7}$ addition in hot-water treatment seem to be the alternative dormancy breaking method to low-temperature treatment in Lilium Oriental Hybrid bulblet regenerated in vitro.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2001.11a
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• pp.87-87
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• 2001

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.193-207
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• 1993

The seed dormancy of weed species is the important mechanisms to unfavorable conditions but it brings about critical problems in weed control. The factors which induced dormancy were varied with species and their physiological conditions. More than 20 of 50 species of dominant weed species showed the seed dormancy. When several physical treatments were given to seeds to break the dormancy, each species showed the different responses. The germination percentage and germination velocity were increased with alternating temperature. The treatment of more than 4 weeks of stratification had strong effect on dormancy breaking. The ${\alpha}-amylase$ activities of germinating seeds were increased in proportional to the period of stratification treatment of dormant seeds. The contents of soluble protein and soluble sugar were changed slightly with stratification.